KR101788943B1 - Organic electroluminescent element, lighting device, and display device - Google Patents

Abstract

An organic electroluminescence element having at least one light emitting layer sandwiched between an anode and a cathode, and a plurality of organic layers including an adjacent layer adjacent to the anode side of the light emitting layer, wherein at least one of the light emitting layers has an emission spectrum At least one phosphorescent luminescent dopant having a maximum peak wavelength at the shortest wavelength side of 470 nm or less and a HOMO value of -4.50 to -5.50 eV and a nonmetal complex represented by the following general formula Wherein the organic electroluminescence element contains a compound having a HOMO value of -4.50 to -5.10 eV.
≪ Formula 1 >

Description

TECHNICAL FIELD [0001] The present invention relates to an organic electroluminescence device, an organic electroluminescence device, a lighting device, and a display device.

TECHNICAL FIELD The present invention relates to an organic electroluminescence device, a lighting device provided with the organic electroluminescence device, and a display device.

An organic electroluminescence element (hereinafter also referred to as an organic EL element) has a structure in which a light emitting layer containing a compound emitting light is sandwiched between a cathode and an anode. By applying an electric field, holes injected from the anode and electrons injected from the cathode (Exciton) is generated by recombining electrons in the light emitting layer, and light emission (fluorescence / phosphorescence) when the exciton is deactivated is used. In addition, the organic EL element is a full solid element composed of a film of an organic material having a thickness of not more than a submicrometer between the electrode and the electrode, and can emit light with a voltage of several V to several tens of volts. It is expected to be used for illumination.

As a development of an organic EL device for practical use, since the report of organic EL devices using phosphorescence from triplet excitation (see, for example, Non-Patent Document 1) from Princeton University, (See, for example, Patent Document 1 and Non-Patent Document 2).

In addition, the organic EL element using phosphorescent light emission has the advantage that the luminous efficiency in principle can be realized approximately four times as compared with the organic EL element using the previous fluorescent light emission. Therefore, Research and development is being carried out all over the world. For example, many compounds have been studied for synthesis based on heavy metal complexes such as iridium complexes (see, for example, Non-Patent Document 3).

As described above, the phosphorescent emission method has a very high potential. However, in the organic EL device using phosphorescence, the method is largely different from the organic EL device using fluorescence emission, and a method of controlling the position of the emission center, It is an important technical problem to secure the efficiency and lifetime of the device.

Recently, a multi-layered type device having a hole transporting layer located on the anode side of the light emitting layer and an electron transporting layer located on the cathode side of the light emitting layer in a form adjacent to the light emitting layer is well known (see, for example, Patent Document 2 ). In addition, a mixed layer using a host compound and a phosphorescent compound as a dopant is often used for the light emitting layer.

In addition, from the viewpoints of display and use in illumination, organic EL devices are required to have high carrier transporting properties and thermally and electrically stable materials because of their high luminous efficiency and long emission lifetime.

In recent years, an illumination light source having a high color temperature and a display having a wide color gamut are required. In order to achieve these, a blue light-emitting dopant having a short wavelength that has a maximum light emission wavelength of 470 nm, more preferably 460 nm or less, is indispensable.

As a blue light-emitting dopant of a short wavelength, a fluorescent light-emitting luminescent dopant having an anthracene or chrysene in its skeleton is well known, but it is disadvantageous in comparison with a phosphorescent luminescent dopant in terms of luminescence efficiency as described above.

On the other hand, there is FIrpic as a material well known as a phosphorescent blue light emitting dopant having a short wavelength. FIrpic has achieved short-wavelength effect by substituting two fluorine atoms for phenylpyridine as a main ligand and using picolinic acid as a side ligand, but since iridium of the central metal is substituted for two fluorine atoms having high electronegativity And the HOMO is very deep as calculated value of about -5.9 eV.

As a result, it becomes difficult to inject holes from the anode side into the light emitting layer, resulting in a poor balance of injection of holes and electrons, a problem of a decrease in recombination probability in the light emitting layer, and an increase in drive voltage.

Further, since the injection balance of the carrier is broken, the recombination region is easily confined to a narrow region near the interface of the transport layer, so that excitons leaks from the light emitting layer to the adjacent transport layer. As a result, there arises a problem of lowering the luminous efficiency and lowering the luminescent lifetime due to deterioration of the material. In addition, since the HOMO is very deep, it is very difficult to select the material to be used for the anode side adjacent layer of the light emitting layer, and the hole injection property is easily affected by the incorporation of a small amount of impurities or the film quality, . On the other hand, when the HOMO is shallow, for example, using a light-emitting dopant that is shallower than -4.50 eV, the compound becomes unstable because the LUMO becomes relatively shallow. And it is easily influenced by an external person such as oxygen, and there is a problem in terms of stability of element performance.

With respect to the above-mentioned problem, for example, in Patent Document 3, a carbazole derivative improved in hole injection and transportability is used for the hole transport layer, thereby achieving a device with high efficiency and a long life. However, the maximum emission wavelength of a luminescent dopant having a phenylpyridine ligand substituted with a fluorine atom and an isopropyl group, which is used in Examples in Patent Document 3, shows the maximum luminescence wavelength exceeding 470 nm as examined by the present inventor, It has been found that the wavelength is long and not a satisfactory level for use in a display having a wide application range or color gamut of color temperature. In addition, the above document does not disclose the relationship between the HOMO of the material used for the luminescent dopant and the adjacent layer.

In the past, various compounds have been disclosed for an organic EL device material, and development of an organic EL device having a high luminous efficiency and a long life at a low driving voltage has been attempted. However, there is a demand for development of an organic EL device in which the performance of the organic EL device is further improved by increasing the performance thereof. In addition, development of an organic EL device suitable for illumination applications with a high color temperature and a display area with a wide color gamut (i.e., good chromaticity) has been desired.

U.S. Patent No. 6,097,147 specification Japanese Patent Application Laid-Open No. 2005-112765 International Publication No. 2011/122132

M. A. Baldo et al., Nature, Vol. 395, 151-145 (1998) M. A. Baldo et al., Nature, Vol. 403, No. 17, 750-753 (2000) S. Lamansky et al., J. Am. Chem. Soc., 123, 4304 (2001)

An object of the present invention is to provide an organic electroluminescence element having a high luminous efficiency, a low driving voltage, a long life and a good chromaticity, and a lighting apparatus and a display apparatus using the element. .

The above object of the present invention is solved by the following means.

1. An organic electro-luminescence device having at least one light-emitting layer sandwiched between an anode and a cathode, and a plurality of organic layers including adjacent layers adjacent to the anode side of the light-emitting layer, wherein at least one layer of the light- Wherein at least one phosphorescent luminescent dopant having a maximum peak wavelength of 470 nm or less and a HOMO value of -4.50 to -5.50 eV in the shortest wavelength side is contained in the luminescence spectrum, Wherein the organic electroluminescence element is a non-metallic complex compound and contains a compound having an HOMO value of -4.50 to -5.10 eV.

(In the formula (1), R represents a substituent, L represents a linking group or a simple bond, Ar ₁ and Ar ₂ represent an aromatic hydrocarbon ring or an aromatic heterocycle.

2. The organic electroluminescent device according to item 1, wherein L in the formula (1) represents a single bond, and Ar ₁ and Ar _{2 each} represent a 6-membered aromatic hydrocarbon ring or a 6-membered aromatic heterocycle. .

3. A compound according to the above ₁ or ₂ , wherein in the general formula (1), Ar ₁ and Ar ₂ are a benzene ring having an indole ring, an azaindole ring, a carbazole ring, an azacarbazole ring or a condensed aromatic heterocyclic group as a substituent Organic electroluminescence device.

4. The organic electroluminescent device according to any one of items 1 to 3, wherein the compound represented by Formula 1 is a compound represented by Formula 11 below.

(In the general formula (11), R ₁₁₁ and R ₁₁₂ represent a hydrogen atom, an alkyl group, an aromatic hydrocarbon ring group or an aromatic heterocyclic group, and the compound represented by the formula (11) may further have a substituent.)

5. The organic electroluminescence device according to any one of items 1 to 3, wherein the compound represented by Formula 1 is represented by Formula 21 or Formula 22 below.

(In the formulas (21) and (22), R ₂₁₁ and R ₂₁₂ represent an alkyl group, an aromatic hydrocarbon ring group or an aromatic heterocyclic group, and the rings Z ₁ to Z ₃ represent a residue forming an aromatic hydrocarbon ring or aromatic heterocycle, .

6. The organic electroluminescent device according to any one of items 1 to 3, wherein the compound represented by Formula 1 is a compound represented by Formula 31 below.

(Wherein R ₃₁₁ and R ₃₁₂ represent a hydrogen atom, an arylsilyl group, an arylphosphoryl group, an aromatic hydrocarbon ring group, an aromatic heterocyclic group, a diarylamino group or an alkyl group, A ₁ to A ₈ each independently represent C -Rx or N, and a plurality of Rx's may be the same or different, and each Rx independently represents a hydrogen atom or a substituent.

7. The organic electroluminescent device according to any one of items 1 to 6, wherein the phosphorescent luminescent dopant is a compound represented by the following formula (41).

(Wherein M represents Ir, Pt, Rh, Ru, Ag or Cu, X ₁ and X ₂ represent a carbon atom or a nitrogen atom, and the ring Z ₁ together with C═C represents a 6-membered aromatic hydrocarbon Or a 5-membered or 6-membered aromatic heterocycle, and the ring Z ₂ , together with X ₁ -X ₂ , represents a 5-membered heterocyclic ring, L 'represents one of monoanionic two-terminal ligands M 'is an integer of 0 to 2, n' is an integer of at least 1, and m '+ n' is 2 or 3.)

8. The organic electroluminescent device according to 7 above, wherein in the compound represented by the above formula (41), the ring Z ₂ represents a substituted or unsubstituted imidazole ring.

9. The organic electroluminescent device according to 7 above, wherein in the compound represented by the above formula (41), the ring Z ₂ represents a substituted or unsubstituted pyrazole ring.

10. The organic electroluminescence device according to 7 above, wherein in the compound represented by the above formula (41), the ring Z ₂ represents a substituted or unsubstituted triazole ring.

11. The organic electroluminescent device according to any one of items 1 to 10, wherein the luminescent color is white.

12. A lighting device comprising the organic electroluminescence device according to any one of 1 to 11 above.

13. A display device comprising the organic electroluminescence device according to any one of 1 to 11 above.

In the present invention, the relationship between the HOMO of the luminescent dopant and the HOMO of the material containing adjacent layers is defined as in the present invention, thereby improving the hole injection property into the luminescent layer and using a compound having a structure represented by the formula 1 in the adjacent layer . Thus, it is possible to provide an organic electroluminescence element which realizes high luminous efficiency and long life, low driving voltage, and good chromaticity, and a lighting apparatus and a display apparatus using the element.

1 is a schematic diagram showing an example of a display device constituted by organic EL elements.
Fig. 2 is a schematic view of the display portion A in Fig. 1. Fig.
3 is a schematic diagram of a pixel.
4 is a schematic diagram of a passive matrix type full color display device relating to the display portion (A) of Fig.
5 is a schematic view of a lighting device.
6 is a schematic diagram of a lighting device.
7 (a) to 7 (e) are schematic configuration diagrams of an organic EL full color display device.

Hereinafter, embodiments for carrying out the present invention will be described in detail, but the present invention is not limited thereto.

&Quot; Organic EL device "

The organic EL device of the present invention has a plurality of organic layers including at least one luminescent layer sandwiched between an anode and a cathode and an adjacent layer adjacent to the anode side of the luminescent layer. At least one of the phosphorescent luminescent dopants having a maximum peak wavelength at the shortest wavelength side of 470 nm and a HOMO value of -4.50 to -5.50 eV is contained in at least one of the luminescent layers in the luminescence spectrum of the solution , A nonmetal complex compound represented by the formula (1) and a HOMO value of -4.50 to -5.10 eV in the adjacent layer.

In the present invention, in consideration of the above-described problems, the inventors of the present invention have found that the HOMO of the luminescent dopant and the HOMO of the material contained in the adjacent layer can be improved in the injection property of holes into the light emitting layer, Is used for the adjacent layer, the injection balance of the carriers into the light emitting layer is improved to separate the recombination region from the vicinity of the interface between the light emitting layer and the adjacent layer. As a result, an organic electroluminescent device compatible both with high light emission efficiency and long life and with high color temperature and wide color gamut was obtained.

Further, since the compound represented by the formula (1) has a ring-opening structure, the molecules are more easily arranged than the trillylamine derivative represented by? -NPD used in the hole transport layer, and as a result, So that the driving voltage can be achieved.

&Quot; Composition layer of organic EL device "

The structure layer of the organic EL element will be described. In the present invention, preferred specific examples of the layer constitution of the organic EL element are shown below, but the present invention is not limited thereto.

(i) anode / hole transporting layer / light emitting layer / electron transporting layer / cathode

(ii) anode / hole transporting layer / light emitting layer / hole blocking layer / electron transporting layer / cathode

(iii) anode / hole transporting layer / light emitting layer / hole blocking layer / electron transporting layer / electron injecting layer / cathode

(iv) anode / hole injecting layer / hole transporting layer / light emitting layer / hole blocking layer / electron transporting layer / electron injecting layer / cathode

In addition to the hole blocking layer, an electron blocking layer may be used as the blocking layer.

When a plurality of luminescent layers are included, a non-luminescent intermediate layer may be provided between the luminescent layers. It is also possible to stack a plurality of light emitting units by using, as one light emitting unit, the organic layer including the light emitting layer excluding the positive electrode and the negative electrode among the above layer constitution. In the plurality of stacked light emitting units, the non-light emitting intermediate layer may be provided between the light emitting units, and the intermediate layer may include the charge generating layer.

It is preferable that the organic EL device of the present invention is a white light emitting layer, and it is preferable that the organic EL device is a lighting device or a display device using them. That is, the organic EL element preferably emits white light.

Each layer constituting the organic EL device of the present invention will be described.

&Quot; Hole transport layer "

The hole transport layer includes a hole transport material having a function of transporting holes, and in a broad sense, the hole injection layer and the electron blocking layer are also included in the hole transport layer. As the hole transporting material, any one of an organic material and an inorganic material may be used, which has either hole injection or transportation or electron barrier property. In the present invention, a plurality of the hole transporting layers may be formed. For example, the hole transporting layer close to the anode side is referred to as a first hole transporting layer and the hole transporting layer adjacent to the light emitting layer side is referred to as a second hole transporting layer.

The present invention is characterized in that the compound represented by the general formula (1) is contained in the adjacent layer of the light emitting layer. Here, the adjacent layer is a layer adjacent to the anode side of the light emitting layer, specifically, a hole transporting layer. However, as described above, since the hole injection layer and the electron blocking layer are also included in the hole transporting layer in a broad sense, when the hole blocking layer and the electron blocking layer are adjacent to the anode side, Compound. When a plurality of hole transporting layers are provided as described above, among the plurality of hole transporting layers, the compound represented by the general formula (1) is contained in the layer adjacent to the anode side of the light emitting layer. For example, when the hole transporting layer close to the anode side is used as the first hole transporting layer and the hole transporting layer adjacent to the light emitting layer side is used as the second hole transporting layer, the second hole transporting layer has the compound represented by the formula (1).

≪ Compound represented by Chemical Formula 1 >

Next, the compound represented by the formula (1) will be described.

The compound represented by the formula (1) is a nonmetal complex compound, and the HOMO value is -4.50 to -5.10 eV.

The value of HOMO in the present invention is a value obtained by using Gaussian 03 (Gaussian 03, Revision D02, M. J. Frisch, et al., Gaussian, Inc., Wallingford CT, 2004.), a software for molecular orbital calculation by Gaussian, USA.

B3LYP / 6-31G * is used as a keyword, the phosphorescent dopant compound is B3LYP / LanL2DZ as a keyword, the compound represented by Formula 1 of the present invention, a host compound, a hole transporting material, and an electron transporting material, To thereby calculate the HOMO value (eV unit conversion value). It is known that there is a high correlation between the calculated value obtained by this method and the experimental value as a background in which these calculated values are effective.

The HOMO value of the compound represented by the formula (1) of the present invention is -4.50 to -5.10 eV.

The reason why the HOMO value is in the above range is that if the value of HOMO is deeper than -5.10 eV, the injection of holes into the light emitting layer is remarkably reduced, resulting in deterioration of efficiency and lifetime. On the other hand, if it is shallower than -4.50 eV, the holes are liable to be stored at the light emitting layer / hole transporting layer interface because the hole trapping property of the dopant of the light emitting layer is strong, and the efficiency and lifetime are similarly decreased. The HOMO value is preferably -4.70 to -5.10 eV.

≪ Formula 1 >

In the general formula (1), R represents a substituent.

Examples of the substituent include a hydrogen atom, an alkyl group (e.g., methyl, ethyl, propyl, isopropyl, (t) butyl, pentyl, (For example, a vinyl group, an allyl group, etc.), an alkynyl group (for example, a propargyl group, a propargyl group, (Such as a phenyl group, a p-chlorophenyl group, a mesityl group, a tolyl group, a xylyl group, a naphthyl group, an anthryl group, an azulenyl group, an acenaphthenyl group, A heterocyclic group (e.g., an epoxy ring, an aziridine ring, a thiiran ring, an oxetane ring, an azetidine ring, a thiadiazine ring, a tetrahydrofuran ring, a tetrahydrofuran ring, Dioxolane ring, pyrrolidine ring, pyrazolidine ring, imidazolidine ring, oxazolidine ring, tetrahydrothio ring Piperazine ring, hexahydropyridazine ring, hexahydropyrimidine ring, piperazine ring, morpholine ring, tetrahydropyran ring, tetrahydropyran ring, tetrahydropyran ring, thiopyran ring, , 1,3-dioxane ring, 1,4-dioxane ring, trioxane ring, tetrahydrothiopyran ring, thiomorpholine ring, thiomorpholine-1,1-dioxide ring, pyranose ring, A carbamoyl group, a carbocyclic [2,2,2] -octane ring and the like), an aromatic heterocyclic group (a pyridyl group, a pyrimidinyl group, a furyl group, a pyrrolyl group, an imidazolyl group, a benzoimidazolyl group, a pyrazolyl group, , Triazolyl group (e.g., 1,2,4-triazol-1-yl group, 1,2,3-triazol-1-yl group and the like), oxazolyl group, benzoxazolyl group, thiazolyl group, A benzoyl group, a benzoyl group, a benzoyl group, a benzoyl group, a benzoyl group, an isoxazolyl group, an isothiazolyl group, a plazanyl group, a thienyl group, a quinolyl group, a benzofuryl group, The A thienyl group, a thienyl group, a thienyl group, a thienyl group, a thienyl group, a thienyl group, a thienyl group, a thienyl group, a thienyl group, a thienyl group, Bromine atom, iodine atom and fluorine atom), an alkoxyl group (e.g., methoxy group, ethoxy group, propyloxy group, pentyloxy group, hexyl group, (E.g., a phenoxy group, a naphthyloxy group, and the like), an acyloxy group, an acyloxy group, an octyloxy group, a dodecyloxy group and the like), a cycloalkoxyl group (e.g. a cyclopentyloxy group, a cyclohexyloxy group, Alkylthio groups such as methylthio group, ethylthio group, propylthio group, pentylthio group, hexylthio group, octylthio group and dodecylthio group), cycloalkylthio groups (for example, cyclopentylthio group And cyclohexylthio), an arylthio group (e.g., phenylthio An aryloxycarbonyl group (e.g., a phenyloxycarbonyl group, a phenyloxycarbonyl group, a naphthylthio group, etc.), an alkoxycarbonyl group (e.g., methyloxycarbonyl group, ethyloxycarbonyl group, butyloxycarbonyl group, octyloxycarbonyl group and dodecyloxycarbonyl group) (For example, an aminosulfonyl group, a methylaminosulfonyl group, a dimethylaminosulfonyl group, a butylaminosulfonyl group, a hexylaminosulfonyl group, a cyclohexylaminosulfonyl group, an octylaminosulfonyl group, an octylaminosulfonyl group, (E.g., a methylureido group, an ethylureido group, a pentylureido group, a cyclohexylureido group, a phenylureido group, a dodecylsulfonyl group, a dodecylsulfonyl group, a phenylaminosulfonyl group, a naphthylaminosulfonyl group and a 2-pyridylaminosulfonyl group) , Octyl ureido group, dodecyl ureido group, phenyl ureido group, naphthyl ureido group, 2-pyridylamino group, etc.), an acyl group (for example, (For example, an acetyl group, an ethylcarbonyl group, a propylcarbonyl group, a pentylcarbonyl group, a cyclohexylcarbonyl group, an octylcarbonyl group, a 2-ethylhexylcarbonyl group, a dodecylcarbonyl group, a phenylcarbonyl group, a naphthylcarbonyl group and a pyridylcarbonyl group) An acetyloxy group, an ethylcarbonyloxy group, a butylcarbonyloxy group, an octylcarbonyloxy group, a dodecylcarbonyloxy group and a phenylcarbonyloxy group), an amide group (for example, methylcarbonylamino group, ethyl A carboxyl group, a carboxyl group, an amino group, a carboxyl group, an amino group, a carboxyl group, an amino group, a carboxyl group, an amino group, a carboxyl group, A thiocarbonylamino group, etc.), a carbamoyl group (e.g., an aminocarbonyl group, a methylaminocarbonyl group, a dimethyl A cyclohexylaminocarbonyl group, an octylaminocarbonyl group, a 2-ethylhexylaminocarbonyl group, a dodecylaminocarbonyl group, a phenylaminocarbonyl group, a naphthylaminocarbonyl group, a 2-pyridylaminocarbonyl group and the like), a cyclic aminocarbonyl group, A sulfinyl group (for example, a methylsulfinyl group, an ethylsulfinyl group, a butylsulfinyl group, a cyclohexylsulfinyl group, a 2-ethylhexylsulfinyl group, a dodecylsulfinyl group, a phenylsulfinyl group, a naphthylsulfinyl group, An arylsulfonyl group, an alkylsulfonyl group or an arylsulfonyl group (e.g., a methylsulfonyl group, an ethylsulfonyl group, a butylsulfonyl group, a cyclohexylsulfonyl group, a 2-ethylhexylsulfonyl group, a dodecylsulfonyl group, a phenylsulfonyl group, (E.g., an amino group, an ethylamino group, a dimethylamino group, a butylamino group, a cyclopentylamino group, a 2-pyridylsulfonyl group, (E.g., diphenylamino group, dinaphthylamino group, phenylnaphthylamino group, etc.), naphthylamino group, 2-pyridylamino group, etc.), nitro (T) butyldimethylsilyl group, triisopropylsilyl group, t-butylsilyl group, t-butyldimethylsilyl group, t-butyldimethylsilyl group, Butyldiphenylsilyl group, triphenylsilyl group, trinaphthylsilyl group, 2-pyridylsilyl group and the like), alkylphosphino group or arylphosphino group (dimethylphosphino group, diethylphosphino group, dicyclohexyl (2-pyridyl) phosphino group, alkylphosphoryl group or arylphosphoryl group (dimethylphosphoryl group, dimethylphosphoryl group, diphenylphosphoryl group, diphenylphosphino group, A diethylphosphoryl group, a dicyclohexylphosphoryl group, a methylphenylphosphoryl group, (2-pyridyl) phosphoryl group), an alkylthiophosphoryl group or an arylthiophosphoryl group (such as a dimethylthiophosphoryl group, a diethylthiophosphoryl group, a dicyclopentylphosphoryl group, (2-pyridyl) thiophosphoryl group) such as a phenylthiophosphoryl group, a hexylthiophosphoryl group, a methylphenylthiophosphoryl group, a diphenylthiophosphoryl group, a dinaphthylthiophosphoryl group, and a di (2-pyridyl) thiophosphoryl group. These substituents may be further substituted by the above-mentioned substituents, or they may be condensed with each other to form a ring.

Further, an alkyl group, an aromatic hydrocarbon ring group, an aromatic heterocyclic group, a heterocyclic group, and a cycloalkyl group are preferable.

L represents a linking group or a simple bonding hand and examples of the linking group include an oxygen atom, a nitrogen atom, a sulfur atom, an amide group, an ester group, a carbonyl group, a sulfonyl group, an alkylene group (e.g., a methylene group, (For example, a phenylene group or the like) or a heteroarylene group, or a combination thereof. Of these linking groups, an oxygen atom, an alkylene group, and an arylene group are preferable. A simple bonding hand is a bonding hand that directly connects the connecting substituents.

Ar ₁ and Ar ₂ represent an aromatic hydrocarbon ring or an aromatic heterocycle.

Examples of the aromatic hydrocarbon ring include a benzene ring, a biphenyl ring, a naphthalene ring, an azulene ring, an anthracene ring, a phenanthrene ring, a pyrene ring, a chrysene ring, a naphthacene ring, a triphenylene ring, an o- a phenanthrene ring, a perylene ring, a pentane ring, a piperazine ring, a pyranthrene ring, an anthraanthrene ring, and the like.

Examples of the aromatic heterocycle include an aromatic heterocycle such as a silyl ring, furan ring, thiophene ring, oxazole ring, pyrrole ring, pyridine ring, pyridazine ring, pyrimidine ring, pyrazine ring, triazine ring, oxadiazole ring, A thiazole ring, an indole ring, a benzimidazole ring, a benzothiazole ring, a benzoxazole ring, a quinoline ring, a quinoxaline ring, a quinazoline ring, a phthalazine ring, a thienothiophen ring, a carbazole ring, A benzopyran ring, a benzopyran ring, a benzofuran ring, a benzothiophene ring, a dibenzofuran ring, a dibenzofuran ring, a dibenzothiophene ring, a benzothiophene ring, Wherein at least one of the carbon atoms constituting the ring is a ring substituted with a nitrogen atom, a benzodifuran ring, a benzodithiophen ring, an acridine ring, a benzoquinoline ring, a phenazin ring, a phenanthridine ring, a phenanthroline ring, ≪ RTI ID = 0.0 > quinidinyl < / RTI > ring, Thiophene ring, naphthothiophene ring, naphthothiophene ring, anthrafuran ring, anthrafuran ring, anthracene ring, anthracene ring, naphthothiophene ring, , A monovalent group derived from an anthiophene ring, an anthradithiophene ring, a thiotrene ring, a phenoxathine ring, a dibenzocarbazole ring, an indolocarbazole ring, a dithienobenzene ring and the like.

The aromatic hydrocarbon ring and aromatic heterocycle represented by Ar ₁ and Ar ₂ may be substituted with a substituent in R above.

Preferably, Ar ₁ represents an aromatic hydrocarbon ring or an aromatic heterocycle, Ar ₂ represents a non-condensed aromatic hydrocarbon ring having a substituent, a non-condensed aromatic heterocycle having a substituent, or a condensed aromatic hydrocarbon ring or a condensed aromatic heterocycle .

It is also preferable that L represents a single bond, and Ar ₁ and Ar ₂ represent a 6-membered aromatic hydrocarbon ring or a 6-membered aromatic heterocycle.

Further, it is more preferable that Ar ₁ and Ar ₂ are a benzene ring having an indole ring, an azindole ring, a carbazole ring, an azacarbazole ring or a condensed aromatic heterocyclic group as a substituent.

As the compound represented by the formula (1), compounds represented by the following formula (11), (21), (22) and (31)

≪ Formula 11 >

In formula (11), R ₁₁₁ and R _{112 each} represent a hydrogen atom, an alkyl group, an aromatic hydrocarbon ring group or an aromatic heterocyclic group, and the compound represented by formula (11) may further have a substituent.

The alkyl group, aromatic hydrocarbon ring group or aromatic heterocyclic group represented by R ₁₁₁ and R ₁₁₂ in the general formula (11) are the same as those described for R, Ar ₁ and Ar ₂ in the general formula (1).

The substituent which the compound represented by the general formula (11) may have is preferably the substituent represented by R in the general formula (1).

In the formula (11), R ₁₁₁ and R ₁₁₂ are more preferably a phenyl group, dibenzofuran, dibenzothiophene or carbazole.

As the compound represented by the formula (11), the compounds represented by the following formulas (12) to (14) are preferable.

R _111, R ₁₁₂ of Formula 12 to 14 is R _111, R _112, and accept the formula (11).

In formulas (12) to (14), R ₁₁₁ and R ₁₁₂ are more preferably a phenyl group, dibenzofuran, dibenzothiophene or carbazole.

Specific examples of the compounds represented by formulas (11) to (14) are shown below, but the present invention is not limited thereto.

<Formula 21, 22>

&Lt; Formula 21 >

(22)

In formulas (21) and (22), R ₂₁₁ and R ₂₁₂ represent an alkyl group, an aromatic hydrocarbon ring group or an aromatic heterocyclic group. The rings Z ₁ to Z ₃ represent a residue which forms an aromatic hydrocarbon ring or aromatic heterocycle and may have a substituent.

The alkyl group, aromatic hydrocarbon ring group or aromatic heterocyclic group in formulas (21) and (22) are the same as those described for R, Ar ₁ and Ar ₂ in formula (1).

Each of the substituents of the rings Z ₁ to Z ₃ is independently hydrogen, an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 11 carbon atoms, an aromatic hydrocarbon ring group having 6 to 12 carbon atoms, or an aromatic heterocyclic group having 3 to 11 carbon atoms, . The substituent of the ring Z ₂ may form a condensed ring together with the ring to which the substituent is bonded. Preferably, rings Z ₁ to Z ₃ are aromatic hydrocarbon rings, more preferably benzene rings. More preferably, the rings Z ₁ to Z ₃ are all benzene rings.

R ₂₁₁ and R ₂₁₂ are preferably an aromatic hydrocarbon ring group or an aromatic heterocyclic group, and more preferably a benzene ring, a pyridine ring, a pyrimidine ring, a triazine ring, or a quinoline ring.

Specific preferred examples of the compound represented by the formula (21) or (22) are shown below, but the present invention is not limited thereto.

(31)

In formula (31), R ₃₁₁ and R ₃₁₂ represent a hydrogen atom, an arylsilyl group, an arylphosphoryl group, an aromatic hydrocarbon ring group, an aromatic heterocyclic group, a diarylamino group or an alkyl group.

R ₃₁₁ and R ₃₁₂ are preferably any one of an arylsilyl group, an arylphosphoryl group, an aromatic hydrocarbon ring group and an aromatic heterocyclic group, more preferably an aromatic hydrocarbon ring group or an aromatic heterocyclic group. Among them, a substituent containing an oxygen atom or a sulfur atom is preferable.

Examples of the aromatic hydrocarbon ring group or aromatic heterocyclic group in R ₃₁₁ and R ₃₁₂ are the same as those described for R, Ar ₁ and Ar ₂ in the above formula (1). Particularly, dibenzofuryl group, dibenzothienyl group and the like can be mentioned as the most preferable substituent.

A ₁ to A ₈ each independently represent C-Rx or N, and a plurality of Rx may be the same or different. Each R x independently represents a hydrogen atom or a substituent.

The substituent is the same as the substituent in R of formula (1).

It is preferable that at least one of Rxs independent of each other is a substituent, and it is more preferable that at least one of Rx is a substituent.

When at least one Rx out of a plurality of Rx independently represents a substituent, it is preferable that at least one of A ₁ , A ₂ and A ₄ is C-Rx, and furthermore, any one or more of A ₁ or A ₂ Is preferably C-Rx, and more preferably, A ₁ is C-Rx.

When at least one Rx among a plurality of independent Rxs independently represents a substituent, Rx is preferably any one of an arylsilyl group, an arylphosphoryl group, an aromatic hydrocarbon ring group, an aromatic heterocyclic group, and a diarylamino group, Furthermore, it is preferably any one of an arylsilyl group, an arylphosphoryl group, an aromatic hydrocarbon ring group and an aromatic heterocyclic group, more preferably an aromatic hydrocarbon ring group or an aromatic heterocyclic group, particularly preferably an aromatic heterocyclic group Do. Among them, a substituent containing an oxygen atom or a sulfur atom is preferable because it has high charge transport ability and high durability against electric charge, and when it is an aromatic heterocyclic group, it has high thermal stability. Particularly, dibenzofuryl group, dibenzothienyl group and the like can be mentioned as the most preferable substituent.

The substituent represented by Rx is preferably further substituted, and the substituent is preferably any one selected from an arylsilyl group, an arylphosphoryl group, an aromatic hydrocarbon ring group, an aromatic heterocyclic group, and a diarylamino group. Further, the arylsilyl group , An arylphosphoryl group, an aromatic hydrocarbon ring group, and an aromatic heterocyclic group, more preferably an aromatic hydrocarbon ring group or an aromatic heterocyclic group.

In the present invention, any one or more of a plurality of Rx, R ₃₁₁ and R ₃₁₂ in the formula (31) is preferably a pyridyl group, a pyrimidinyl group, a furyl group, a pyrrolyl group, an imidazolyl group, A thiazolyl group, an isothiazolyl group, an isothiazolyl group, a plazanyl group, a thienyl group, a quinolyl group, a benzofuryl group, a diazo group, a thiazolyl group, a thiazolyl group, A benzothienyl group, a dibenzothienyl group, an indolyl group, an indoloindolyl group, a quinoxalinyl group, a pyridazinyl group, a triazinyl group, a quinazolinyl group, a phthalazinyl group, an arylsilyl group, And a fluorine group.

Specific preferred examples of the compound represented by the general formula (31) are shown below, but the present invention is not limited thereto.

In addition to the compound represented by the general formula (1) of the present invention, a plurality of known hole transporting materials may be used in combination as long as the effect of the present invention is not impaired.

Examples of the hole transporting material include a hole transporting material such as a triazole derivative, an oxadiazole derivative, an imidazole derivative, a polyarylalkane derivative, a pyrazoline derivative and a pyrazolone derivative, a phenylenediamine derivative, an arylamine derivative, A styryl anthracene derivative, a fluorenone derivative, a hydrazone derivative, a stilbene derivative, a silazane derivative, an aniline-based copolymer, and a conductive polymer oligomer, particularly a thiophenol oligomer.

As the hole transporting material, those described above can be used, but it is preferable to use a porphyrin compound, an aromatic tertiary amine compound, and a styrylamine compound, especially an aromatic tertiary amine compound.

Representative examples of aromatic tertiary amine compounds and styrylamine compounds include N, N, N ', N'-tetraphenyl-4,4'-diaminophenyl; N, N'-diphenyl-N, N'-bis (3-methylphenyl) - [1,1'-biphenyl] -4,4'-diamine (TPD); 2,2-bis (4-di-p-trilaminophenyl) propane; 1,1-bis (4-di-p-trilaminophenyl) cyclohexane; N, N, N ', N'-tetra-p-tolyl-4,4'-diaminobiphenyl; 1,1-bis (4-di-p-trilaminophenyl) -4-phenylcyclohexane; Bis (4-dimethylamino-2-methylphenyl) phenylmethane; Bis (4-di-p-trilaminophenyl) phenylmethane; N, N'-diphenyl-N, N'-di (4-methoxyphenyl) -4,4'-diaminobiphenyl; N, N, N ', N'-tetraphenyl-4,4'-diaminodiphenyl ether; 4,4'-bis (diphenylamino) quadriphenyl; N, N, N-tri (p-tolyl) amine; 4- (di-p-tolylamino) -4 '- [4- (di-p-tolylamino) styryl] stilbene; 4-N, N-diphenylamino (2-diphenylvinyl) benzene; 3-methoxy-4'-N, N-diphenylaminostilbene; N-phenylcarbazole and those having two condensed aromatic rings described in the specification of U.S. Patent No. 5,061,569, for example, 4,4'-bis [N- (1-naphthyl) -N- Phenylamino] biphenyl (NPD), and triphenylamine unit described in JP-A-4-308688 are bonded in a star burst form to 4,4 ', 4 "-tris [N- (3- ) -N-phenylamino) triphenylamine (MTDATA).

It is also possible to use a polymer material in which these materials are introduced into the polymer chains, or a polymer material having these materials as the main chain of the polymer. Inorganic compounds such as p-type Si and p-type SiC can also be used as a hole injecting material and a hole transporting material. In addition, cyclometallized complexes such as copper phthalocyanine and tris (2-phenylpyridine) iridium complexes and orthometallized complexes can also be used as the hole transporting material.

Japanese Patent Application Laid-Open No. 11-251067, J. Huang et. a so-called p-type hole transporting material as described in that document (Applied Physics Letters 80 (2002), p.139) may be used.

A hole transporting layer doped with an impurity and having a high p-type property may also be used. Examples thereof include those disclosed in Japanese Patent Application Laid-Open Nos. 4-297076, 2000-196140, 2001-102175, J. Appl. Phys., 95, 5773 (2004), and the like.

The hole transporting layer can be formed by thinning the hole transporting material by a known method such as a printing method including a vacuum evaporation method, a spin coating method, a casting method, an ink jet method, and the LB method. The film thickness of the hole transporting layer is not particularly limited, but is usually about 5 nm to 5 탆, preferably 5 nm to 200 nm.

<Electron transport layer>

The electron transport layer includes a material having a function of transporting electrons, and in a broad sense, the electron injection layer and the hole blocking layer are also included in the electron transport layer. The electron transporting layer may be a single layer or a plurality of layers. As the electron transporting material (including the hole blocking material and the electron injecting material) used in the electron transporting layer, it is sufficient that it has a function of transferring electrons injected from the cathode to the light emitting layer. As the constituent material of the electron transporting layer, It is possible to use them singly or in combination.

Examples of conventionally known materials (hereinafter, referred to as electron transporting materials) used in the electron transporting layer include, for example, nitro-substituted fluorene derivatives, diphenylquinone derivatives, thiopyran oxide derivatives, heterocyclic tetracarboxylic acids such as naphthalene perylene Anhydrides, carbodiimides, pre-phenylidenemethane derivatives, anthraquinodimethane and anthrone derivatives, oxadiazole derivatives, azacarbazole derivatives including carbene derivatives, and the like.

Here, the azacarbazole derivative means that at least one carbon atom constituting the carbazole ring is substituted with a nitrogen atom.

In the oxadiazole derivative, a thiadiazole derivative in which an oxygen atom of the oxadiazole ring is substituted with a sulfur atom, and a quinoxaline derivative having a quinoxaline ring, which is known as an electron-withdrawing group, can also be used as an electron transporting material.

These materials may be introduced into the polymer chains, or a polymer material containing these materials as the main chain of the polymer may be used.

Also, metal complexes of 8-quinolinol derivatives such as tris (8-quinolinol) aluminum (Alq), tris (5,7-dichloro-8-quinolinol) aluminum, tris (8-quinolinol) aluminum, dibromo-8-quinolinol) aluminum, tris (2-methyl- Znq), and metal complexes in which the center metal of these metal complexes is substituted with In, Mg, Cu, Ca, Sn, Ga or Pb can also be used as an electron transporting material.

Other metal-free or metal phthalocyanine or its terminal end substituted with an alkyl group or a sulfonic acid group can also be used as an electron transporting material.

In addition, inorganic semiconductors such as n-type Si and n-type SiC, as well as the hole injecting layer and the hole transporting layer, can also be used as an electron transporting material.

The electron transporting layer may be formed by a method in which an electron transporting material is formed by using an electron transporting material such as a vacuum evaporation method, a wet method (also referred to as a wet process, such as a spin coating method, a casting method, a die coating method, a blade coating method, Coating method, curtain coating method, LB method (Langmuir Blodgett method), or the like), or the like.

The thickness of the electron transporting layer is not particularly limited, but is usually about 5 nm to 5000 nm, preferably 5 nm to 200 nm. The electron transporting layer may have a single-layer structure including one or more of the above materials.

Further, an n-type dopant such as a metal complex, a metal halide, or a metal compound may be used by being doped.

Examples of conventionally known compounds (electron transporting materials) preferably used for forming the electron transporting layer include ET-1-ET-43 compounds described in JP-A-2012-164731, It is not limited.

<Light Emitting Layer>

The light emitting layer is a layer in which electrons and holes injected from the electrode or the electron transporting layer and the hole transporting layer are recombined to emit light. The light emitting portion may be within the layer of the light emitting layer, or may be the interface between the light emitting layer and the adjacent layer.

The sum of the film thicknesses of the light emitting layers is not particularly limited but may be adjusted within a range of 2 nm to 5 占 퐉 in terms of uniformity of the film and prevention of application of unnecessary high voltage at the time of light emission, More preferably in the range of 2 nm to 200 nm, and particularly preferably in the range of 5 nm to 100 nm.

The light emitting layer may be produced by a method in which a light emitting dopant or a host compound to be described later is vapor-deposited by a vacuum evaporation method, a wet method (also referred to as a wet process, such as a spin coating method, a casting method, a die coating method, A roll coating method, a LB method (Langmuir Blodgett method), and the like), or the like.

The light emitting layer of the organic EL device of the present invention contains a luminescent dopant (a phosphorescent dopant, a phosphorescent dopant, a phosphorescent dopant, a fluorescent dopant, etc.) and a host compound.

(Luminescent dopant compound)

A luminescent dopant compound (also referred to as a luminescent dopant or a luminescent dopant compound) will be described.

As the luminescent dopant, a fluorescent dopant (also referred to as a fluorescent compound), a phosphorescent dopant (a phosphorescent dopant compound, a phosphorescent emitter, a phosphorescent compound, a phosphorescent compound or the like) may be used.

(Phosphorescent luminescent dopant)

The phosphorescent luminescent dopant will be described.

The phosphorescent luminescent dopant compound is a compound in which luminescence from the excitation triplet is observed. Concretely, it is defined as a compound which emits phosphorescence at room temperature (25 캜), and a phosphorescent quantum yield of not less than 0.01 at 25 캜, but a preferable phosphorescence quantum yield is not less than 0.1.

The phosphorescent quantum yield can be measured by the method described in Spectroscopy II, 3rd edition, Experimental Chemistry Lecture 7, page 398 (1992, Maruzen). The phosphorescent quantum yield in the solution can be measured using various solvents, but the phosphorescent luminescent dopant may achieve the phosphorescent quantum yield (0.01 or more) in any one of the solvents.

The phosphorescent luminescent dopant can be luminescent in principle in two ways, one of which is the recombination of carriers on the host compound on which the carrier is transported, so that an excited state of the luminescent host compound is generated, and this energy is transferred to the phosphorescent dopant, The other is the carrier trap type in which the phosphorescent dopant becomes the carrier trap, the recombination of the carriers occurs on the phosphorescent luminescent dopant, and the luminescence from the phosphorescent luminescent dopant compound is obtained. In either case , The excited state energy of the phosphorescent luminescent dopant is lower than the excited state energy of the host compound.

The inventors of the present invention have conducted intensive studies in order to achieve the object of the present invention. As a result, the present inventors have found that, in at least one layer of the light emitting layer of the organic EL device, in the luminescence spectrum in the solution, It has also been found that by including at least one phosphorescent dopant having a HOMO value of -4.50 to -5.50 eV, it is possible to improve the luminous efficiency, lifetime, drive voltage and color gamut of the device of the organic EL device .

Accordingly, the phosphorescent luminescent dopant used in the present invention is a phosphorescent luminescent dopant for use in the present invention in which at least one species has a maximum peak wavelength at the shortest wavelength side of 470 nm or less in the luminescence spectrum of a solution in the region of 400 to 700 nm, -5.50 eV.

The phosphorescent luminescent dopant used in the present invention has a maximum luminescence maximum wavelength (peak wavelength) of the luminescence at the shortest wave side of 470 nm or less when there are a plurality of luminescence peaks in the luminescence spectrum in the solution.

When the maximum emission wavelength exceeds 470 nm, it is also unsuitable for use in a high color temperature illumination application or a wide color display. Therefore, the maximum luminescence wavelength of the phosphorescent luminescent dopant is 470 nm or less.

The luminescence spectrum in the solution can be obtained, for example, from a fluorescence spectrum obtained by irradiating excitation light to a solution in which a dopant is dissolved in a non-polar solvent. In the present invention, the dopant was dissolved in 2-methyltetrahydrofuran, and the fluorescence spectrum of the 400 to 700 nm region was measured using Hitachi F-4500.

The HOMO value of the phosphorescent luminescent dopant used in the present invention is -4.50 to -5.50 eV. The value of HOMO in the phosphorescent luminescent dopant can be obtained by the calculation method described in the hole transport layer.

When the HOMO value is deeper than -5.50 eV, the HOMO value falls within the above range, because the hole injection property into the light emitting layer is significantly reduced from the hole transporting layer, resulting in deterioration of the efficiency and lifetime. On the other hand, if the HOMO value is shallower than -4.50 eV, the LUMO of the dopant becomes shallow or the compound becomes unstable in order to obtain a blue phosphorescent light emitting dopant having a maximum luminescence wavelength of 470 nm or less.

In the present invention, a preferred phosphorescent luminescent dopant is a compound represented by the following formula (41).

&Lt; EMI ID =

X ₁ and X ₂ represent a carbon atom or a nitrogen atom, and the ring Z ₁ , together with C = C, forms a 6-membered aromatic hydrocarbon ring together with C = C, Or a 5-membered or 6-membered aromatic heterocycle, and the ring Z ₂ together with X ₁ -X ₂ represents a 5-membered heterocyclic ring.

Examples of the six-membered aromatic hydrocarbon ring of ring Z ₁ include a benzene ring. Examples of the 5-membered or 6-membered aromatic heterocycle include furan ring, thiophene ring, oxazole ring, pyrrole ring, pyridine ring, pyridazine ring, pyrimidine ring, pyrazine ring, triazine ring, oxadiazole ring, , Imidazole ring, pyrazole ring, thiazole ring and the like. Ring Z ₁ and ring Z ₂ may have a substituent, and those in R in Formula (1) may be used.

M 'is an integer of 0 to 2, n' is an integer of at least 1, and m '+ n' is 2 or 3, and L 'is one or more monoanionic double- .

The ring Z ₁ represents a substituted or unsubstituted benzene ring or pyridine ring, a ring Z ₂ represents a substituted or unsubstituted imidazole ring, a substituted or unsubstituted pyrazole ring, or a substituted or unsubstituted triazole ring .

Preferred as the compound represented by the formula (41) are the compounds represented by the following formulas (42), (43) and (44).

In the formula (42), M, L ', m' and n 'are synonymous with the formula (41). R ₁ represents an electron attracting group, and R ₂ represents an electron donating group or F. X ₁ and X ₂ represent a carbon atom or a nitrogen atom, and the ring Z ₂ together with X ₁ -X ₂ represents a 5-membered heterocyclic ring. Examples of the electron attracting group include a keto group such as a halogen atom, a cyano group, a nitro group, a phenyl group and an acyl group. Examples of the electron donating group include an alkyl group, a hydroxyl group, an alkoxy group and an amino group.

In formula (43), M, L ', m' and n 'are as defined in formula (41). R ₃ , R ₄ and R ₅ represent a hydrogen atom or a substituent, and R ₄ and R ₅ may form a ring. The ring Z ₁ , together with C = C, represents a 6-membered aromatic hydrocarbon ring or a 5-membered or 6-membered aromatic heterocycle.

The substituent of R ₃ , R ₄ and R _{5 represents} a group which is the same as the substituent represented by R in formula (1).

In the formula (44), M, L ', m' and n 'are synonymous with the formula (41). X ₁ to X ₄ represent -CR ₆ or a nitrogen atom, and when X ₃ and X ₄ are -CR ₆ , a ring may be formed. The ring Z ₃ represents a 6-membered aromatic hydrocarbon ring or a 5-membered or 6-membered aromatic heterocycle, and the ring Z ₄ , together with X ₁ -X ₂ , represents a 5-membered heterocyclic ring. R ₆ represents a carbon atom or a nitrogen atom.

Specific examples of the formulas (41) to (44) are shown below, but the present invention is not limited thereto.

In addition to the phosphorescent luminescent dopant according to the present invention, compounds described in the following patent publications may be used in combination.

For example, International Publication WO 00/70655, JP-A-2002-280178, JP-A-2001-181616, JP-A-2002-280179, JP-A-2001-181617 Japanese Patent Application Laid-Open Nos. 2002-280180, 2001-247859, 2002-299060, 2001-313178, 2002-302671 Japanese Patent Laid-Open Nos. 2001-345183, 2002-324679, 02/15645, 2002-332291, 2002-50484, Japanese Unexamined Patent Publication No. 2002-332292, Japanese Unexamined Patent Publication No. 2002-83684, Japanese Unexamined Patent Publication No. 2002-540572, Japanese Unexamined Patent Publication No. 2002-117978, Japanese Unexamined Patent Publication No. 2002-338588, Japanese Patent Application Laid-Open No. 2002-170684, Japanese Patent Application Laid-Open No. 2002-35296 No. 0, International Publication No. 01/93642, No. 2002-50483, No. 2002-100476, No. 2002-173674, No. 2002-359082 Japanese Patent Application Laid-Open No. 2002-175884, Japanese Patent Application Laid-Open Nos. 2002-363552, 2002-184582, 2003-7469, 2002-525808 Japanese Patent Application Laid-Open No. 2003-7471, Japanese Patent Application Laid-Open Nos. 2002-525833, 2003-31366, 2002-226495, 2002-234894 Japanese Patent Laid-Open Publication No. 2002-235076, Japanese Patent Application Laid-Open Nos. 2002-241751, 2001-319779, 2001-319780, 2002-62824 Japanese Patent Application Laid-Open No. 2002-100474, Japanese Patent Laid- 2002-203679, 2002-343572, 2002-203678, and the like.

(A fluorescent dopant (also referred to as a fluorescent compound))

Examples of the fluorescent dopant include coumarin dye, pyran dye, cyanine dye, chromanium dye, squarylium dye, oxobenzanthracene dye, fluororesin dye, rhodamine dye, pyryllum dye, A benzo dye, a polythiophene dye or a rare earth complexion fluorescent substance, and a compound having a high fluorescent quantum yield represented by a laser dye.

The luminescent dopant may be used in combination with a plurality of compounds, or a phosphorescent dopant having a different structure may be used, or a phosphorescent dopant and a fluorescent dopant may be used in combination.

&Lt; luminescent host compound (also referred to as luminescent host, host compound)

Specific examples of the known luminescent host include the compounds described in the following literatures.

Japanese Patent Laid-Open Nos. 2001-257076, 2002-308855, 2001-313179, 2002-319491, 2001-357977, 2002-334786, 2002-8860 2002-334787, 2002-15771, 2002-334788, 2002-43056, 2002-334789, 2002-75645, 2002-338579 , 2002-105445, 2002-343568, 2002-141173, 2002-352957, 2002-203683, 2002-363227, 2002-231453, 2003-3165, 2002-234888, 2003-27048, 2002-255934, 2002-260861, 2002-280183, 2002-299060, and the like 2002-302516, 2002-305083, 2002-305084, 2002-308837, etc.

Specific examples of the light-emitting host of the light-emitting layer of the organic EL device of the present invention include the compounds of OC-1 to OC32 described in, for example, Japanese Patent Application Laid-Open No. 1464731, but are not limited thereto .

&Lt; Injection layer: Hole injection layer (anode buffer layer), electron injection layer (cathode buffer layer) >

The injection layer is a layer provided between the electrode and the organic layer for the purpose of lowering the driving voltage or improving the light emission luminance as required. The organic EL element and its industrial frontier (published on Nov. 30, 1998 by N.T.S.) (Anode buffer layer) and an electron injection layer (cathode buffer layer) are described in detail in Chapter 2, &quot; Electrode Material &quot; (pages 123 to 166).

Details of the anode buffer layer (hole injection layer) are also disclosed in Japanese Patent Application Laid-Open Nos. 9-45479, 9-260062 and 8-288069, and specific examples thereof include phthalocyanine represented by copper phthalocyanine A buffer layer made of an oxide such as vanadium oxide, an amorphous carbon buffer layer, a polymer buffer layer using a conductive polymer such as polyaniline (emeraldine) or polythiophene, a tris (2-phenylpyridine) iridium complex, And the like.

Details of the cathode buffer layer (electron injecting layer) are also disclosed in Japanese Patent Application Laid-Open Nos. 6-325871, 9-17574, 10-74586, and the like. Specifically, they are represented by strontium and aluminum An alkali metal compound buffer layer typified by lithium fluoride, sodium fluoride or potassium fluoride; an alkaline earth metal compound buffer layer typified by magnesium fluoride; and an oxide buffer layer typified by aluminum oxide. The buffer layer (injection layer) is preferably an extremely thin film, and it is preferable that the thickness of the buffer layer (injection layer) is in the range of 0.1 nm to 5 mu m.

The material used for the anode buffer layer and the cathode buffer layer can be used in combination with other materials, and for example, they can be mixed in a hole transporting layer or an electron transporting layer.

<Blocking layer: hole blocking layer, electron blocking layer>

The blocking layer is provided as necessary in addition to the basic constituent layer of the organic compound thin film as described above. For example, Japanese Patent Application Laid-Open Nos. 11-204258 and 11-204359, and 237 pages of "Organic EL device and its industrial frontier" (issued on Nov. 30, 1998 N · T · S company) Hole blocking layer (hole block) layer.

The hole blocking layer includes a hole blocking material having a function of an electron transporting layer in a broad sense, a function of transporting electrons and a capability of transporting holes, and a hole blocking material having a function of transporting electrons, The probability of recombination can be improved.

In addition, the above-described electron transporting layer structure can be used as a hole blocking layer according to the present invention, if necessary.

The hole blocking layer of the organic EL device of the present invention is preferably provided adjacent to the light emitting layer.

Examples of the hole blocking layer include a carbazole derivative, an azacarbazole derivative (wherein the azacarbazole derivative means that at least one carbon atom constituting the carbazole ring is substituted with a nitrogen atom), a pyridine derivative, etc., Is preferably contained.

Further, in the present invention, when a plurality of luminescent layers having different luminescent colors are provided, it is preferable that the luminescent layer (the shortest layer) having the luminescent peak wavelength in the shortest wavelength is closest to the anode among the luminescent layers. In this case, it is preferable that a hole blocking layer is additionally provided between the shortest folding layer and the light emitting layer next to the anode in the shortest folding layer.

The film thickness of the hole blocking layer and the electron blocking layer which can be used in the present invention is preferably from 3 nm to 100 nm, and more preferably from 3 nm to 30 nm.

<Anode>

As the anode in the organic EL device, a material having a large work function (4 eV or more), an alloy, an electrically conductive compound, or a mixture thereof is preferably used as an electrode material. Specific examples of such electrode materials include metals such as Au and conductive transparent materials such as CuI, indium tin oxide (ITO), SnO ₂ , and ZnO.

A material capable of forming a transparent conductive film with an amorphous state, such as IDIXO (In ₂ O ₃ -ZnO), may also be used. The anode may be formed by forming a thin film of the electrode material by a method such as vapor deposition or sputtering, forming a pattern of a desired shape by a photolithography method, or when the pattern precision is not required to be small (about 100 μm or more) A pattern may be formed through a mask of a desired shape at the time of depositing or sputtering the electrode material.

Alternatively, when a material that can be applied, such as an organic conductive compound, is used, a wet film formation method such as a printing method or a coating method may be used. When light emission is taken out from this anode, it is preferable that the transmittance is made larger than 10%, and the sheet resistance as the anode is preferably several hundreds of ohm / square or less. Though the film thickness varies depending on the material, it is usually selected in the range of 10 nm to 1000 nm, preferably 10 nm to 200 nm.

<Cathode>

On the other hand, as the cathode, a material having a small work function (4 eV or less), a metal (referred to as electron injectable metal), an alloy, an electrically conductive compound, and a mixture thereof is used as an electrode material.

Specific examples of such electrode materials include sodium, sodium-potassium alloy, magnesium, lithium, a magnesium / copper mixture, a magnesium / silver mixture, a magnesium / aluminum mixture, a magnesium / indium mixture, an aluminum / aluminum oxide (Al ₂ O ₃ ) Indium, a lithium / aluminum mixture, a rare earth metal, and the like.

Among them, a mixture of an electron-injecting metal and a second metal which is a metal having a larger work function value than that of the electron-injecting metal, for example, a magnesium / silver mixture, a magnesium / aluminum mixture, A magnesium / indium mixture, an aluminum / aluminum oxide (Al ₂ O ₃ ) mixture, a lithium / aluminum mixture, aluminum and the like are suitable.

The negative electrode can be produced by forming the thin film by a method such as vapor deposition or sputtering. The sheet resistance as the cathode is preferably several hundreds? /? Or less, and the film thickness is usually selected in the range of 10 nm to 5 占 퐉, preferably 50 nm to 200 nm.

Further, if either the anode or the cathode of the organic EL element is transparent or semitransparent in order to transmit the emitted light, the light emission luminance is preferably improved.

A transparent or semitransparent negative electrode can be fabricated by fabricating the above-described metal with a film thickness of 1 nm to 20 nm on the negative electrode and then forming a conductive transparent material exemplified in the explanation of the positive electrode thereon. Can be fabricated.

&Quot; Support substrate &quot;

As the support substrate (hereinafter also referred to as a substrate, a substrate, a support, and the like) usable in the organic EL device of the present invention, there is no particular limitation on the kind of glass, plastic or the like, and it may be transparent or opaque. When light is taken out from the support substrate side, the support substrate is preferably transparent.

Examples of transparent support substrates that are preferably used include glass, quartz, and transparent resin films. A particularly preferable supporting substrate is a resin film capable of imparting flexibility to the organic EL element.

&Quot; Method of manufacturing organic EL device &quot;

As an example of a manufacturing method of an organic EL device, a method of manufacturing an element including an anode / a hole injection layer (anode buffer layer) / a hole transport layer / a light emitting layer / a hole blocking layer / an electron transport layer / an electron injection layer (cathode buffer layer) / a cathode do.

First, a thin film containing a desired electrode material, for example, a positive electrode material, is formed on a suitable gas to a thickness of 1 mu m or less, preferably 10 nm to 200 nm, to prepare a positive electrode.

Subsequently, a thin film containing an organic compound such as a hole injection layer, a hole transporting layer, a light emitting layer, a hole blocking layer, an electron transporting layer, and an electron injecting layer, which is a device material, is formed thereon.

The thin film can be formed by, for example, vacuum evaporation, wet process (also referred to as wet process), or the like.

Examples of the wet method include spin coating, casting, die coating, blade coating, roll coating, inkjet, printing, spray coating, curtain coating and LB. From the viewpoint of high productivity, a roll-to-roll type high-fidelity method such as a die coating method, a roll coating method, an ink jet method, and a spray coating method is preferable. Further, different film forming methods may be applied to each layer.

Examples of the liquid medium for dissolving or dispersing the organic EL material usable in the present invention include ketones such as methyl ethyl ketone and cyclohexanone, fatty acid esters such as ethyl acetate, halogenated hydrocarbons such as dichlorobenzene, Aliphatic hydrocarbons such as cyclohexane, decalin and dodecane, and organic solvents such as DMF and DMSO can be used.

As the dispersion method, dispersion can be carried out by a dispersion method such as ultrasonic wave, high shear force dispersion or media dispersion.

After the formation of this layer, a thin film containing a material for a negative electrode is formed thereon to a film thickness of 1 mu m or less, preferably 50 to 200 nm, and a cathode is provided to obtain a desired organic EL device.

It is also possible to fabricate the cathode, the electron injection layer, the electron transport layer, the hole blocking layer, the light emitting layer, the hole transport layer, the hole injection layer, and the anode in this order in reverse order.

The production of the organic EL device of the present invention is preferably carried out from the hole injection layer to the cathode in one vacuum evaporation step, but it may be carried out in the middle to carry out another film formation method. At this time, it is preferable to carry out the work in a dry inert gas atmosphere.

"Sealing"

Examples of the sealing means used in the present invention include a method of bonding the sealing member to the electrode and the supporting substrate with an adhesive.

The sealing member may be disposed so as to cover the display area of the organic EL element, or may be a concave plate or a flat plate. In addition, transparency and electric insulation are not particularly limited. Specific examples thereof include glass plates, polymer plates and films, metal plates and films. Sandblasting, chemical etching, or the like is used to process the sealing member into a concave shape.

It is also possible to appropriately form the sealing film by covering the electrode and the organic layer on the outside of the electrode opposite to the supporting substrate sandwiching the organic layer and forming the inorganic or organic layer in contact with the supporting substrate.

"Shield, Shield"

A protective film or a protective plate may be provided on the sealing film on the side opposite to the supporting substrate sandwiching the organic layer or on the outside of the sealing film in order to increase the mechanical strength of the device. Particularly, when the sealing is performed by the sealing film, the mechanical strength is not necessarily high, and therefore it is preferable to provide such a protective film and a protective plate.

A glass plate, a polymer plate and a film, a metal plate and a film, which are the same as those used for the above sealing, can be used as the material usable for this, but it is preferable to use a polymer film in view of light weight and thinning.

"Light extraction"

It is generally said that an organic EL element emits light in a layer having a refractive index higher than that of air (refractive index is about 1.7 to 2.1) and can extract only 15% to 20% of light generated in the light emitting layer. This means that the light incident on the interface (interface between the transparent substrate and the air) at an angle? Greater than the critical angle can not be totally extracted to the outside of the device due to total reflection and light is totally reflected between the transparent electrode and the light- And the light is guided from the transparent electrode to the light emitting layer, and as a result, the light escapes to the side direction of the device.

As a method for improving the extraction efficiency of this light, for example, a method of forming irregularities on the surface of a transparent substrate to prevent total reflection at the air interface with the transparent substrate (US Pat. No. 4,774,435) (Japanese Unexamined Patent Application Publication No. 63-314795), a method of forming a reflective surface on the side surface of a device (JP-A-1-220394), a method of forming an intermediate refractive index A method of introducing a flat layer to form an antireflection film (Japanese Patent Application Laid-Open No. 62-172691), a method of introducing a flat layer having a lower refractive index than a substrate between a substrate and a light emitting body (JP-A-2001-202827 (Japanese Unexamined Patent Application Publication No. 11-283751), a method of forming a diffraction grating on a substrate, a transparent electrode layer, and a light-emitting layer (including a substrate and an outer space).

In the present invention, these methods can be used in combination with the organic EL device of the present invention, but a method of introducing a flat layer having a lower refractive index than the substrate between the substrate and the light emitting body, A method of forming a diffraction grating on the substrate (including the substrate and the outside world) may be suitably used.

By combining these means in the present invention, a device having higher brightness or better durability can be obtained.

&Quot;

The organic EL device of the present invention is fabricated so as to have a structure of, for example, a microlens array shape on the light extraction side of the substrate, or by combining with a so-called condensing sheet, It is possible to increase the luminance in a specific direction.

As an example of the microlens array, a quadrangular pyramid having a side of 30 mu m and a vertex angle of 90 DEG is arranged two-dimensionally on the light extraction side of the substrate. One side is preferably 10 탆 to 100 탆. If it is smaller than this, the effect of diffraction is generated and colored, whereas if it is too large, the thickness becomes thick, which is not preferable.

In addition to the characteristic parts of the present invention relating to the above-described "layers constituting the organic EL device", the term "supporting substrate", "sealing", "protective film, protective plate", "light extraction" The details of the other aspects of the present invention may be the same as those described in known documents such as Japanese Patent Laid-Open Publication No. 2012-164731 and Japanese Laid-Open Patent Application No. 2012-156299.

"Usage"

The organic EL device of the present invention can be used as a display device, a display, and various luminescent light sources. As a luminescent light source, it is possible to use a light source such as a lighting device (household lighting, in-vehicle lighting), a backlight for a clock or a liquid crystal, a sign advertising, a signal device, a light source for an optical storage medium, a light source for an electrophotographic copying machine, However, the present invention is not limited to this, and it can be effectively used particularly for a backlight of a liquid crystal display device and as a light source for illumination.

In the organic EL device of the present invention, patterning may be carried out by a metal mask, an inkjet printing method or the like at the time of film formation, if necessary. In the case of patterning, only the electrode may be patterned, the electrode and the light emitting layer may be patterned, or the entire device layer may be patterned, and conventionally known methods may be used in manufacturing the device.

The color emitted by the organic EL device of the present invention or the compound according to the present invention is shown in Figure 4.16 on page 108 of "New Color Science Handbook" (published by the Japan Color Association, Tokyo University Publications, 1985) -1000 (manufactured by Konica Minolta Sensing Co., Ltd.) is applied to the CIE chromaticity coordinates.

When the organic EL device of the present invention is a white color element, the white color means that the chromaticity in the CIE 1931 coloring system at 1000 cd / m 2 is 0.33 ± 0.07, Y = 0.33 ± 0.1.

"Display"

The display device of the present invention will be described. The display device of the present invention comprises the organic EL device of the present invention.

The display device of the present invention may be monochromatic or multicolored, but the multicolor display device will be described here.

In the case of a multicolor display apparatus, a shadow mask may be provided only at the time of forming a light emitting layer, and a film may be formed on one surface by a vapor deposition method, a casting method, a spin coating method, an inkjet method, or a printing method.

In the case of patterning only the light emitting layer, the method is not limited, but preferably a vapor deposition method, an ink jet method, a spin coating method, and a printing method.

The configuration of the organic EL element included in the display device is selected from among the above-described examples of the organic EL element as necessary.

The manufacturing method of the organic EL device is as shown in one form of production of the organic EL device of the present invention.

When a DC voltage is applied to the obtained multicolor display device, light emission can be observed by applying a voltage of about 2 V to 40 V with the polarity of the positive polarity being positive and the polarity of the negative polarity being negative. In addition, even if a voltage is applied in the opposite polarity, no current flows and no light emission occurs at all. When an AC voltage is applied, the light is emitted only when the positive polarity is positive and the negative polarity is negative. Further, the waveform of the applied alternating current may be arbitrary.

The multicolor display device can be used as a display device, a display, and various luminescent light sources. In display devices and displays, full-color display is possible by using three types of organic EL elements for blue, red and green light emission.

Examples of the display device and the display include a television, a personal computer, a mobile device, an AV device, a character broadcast display, and an information display in a car. Particularly, it can be used as a display device for reproducing a still image or a moving image, and a driving method when used as a display device for moving picture reproduction can be either a simple matrix (passive matrix) method or an active matrix method.

Examples of the luminescent light source include a home light, a vehicle light, a backlight for a clock or a liquid crystal display, a sign advertising, a signal light, a light source for an optical storage medium, a light source for an electrophotographic copying machine, Are not limited to these.

Hereinafter, an example of a display device having the organic EL device of the present invention will be described with reference to the drawings.

1 is a schematic diagram showing an example of a display device constituted by organic EL elements. And is a schematic view of a display such as a cellular phone in which image information is displayed by light emission of the organic EL element.

The display 1 includes a display section A having a plurality of pixels, a control section B performing image scanning of the display section A based on image information, and the like.

The control section B is electrically connected to the display section A and sends a scan signal and an image data signal to each of the plurality of pixels based on image information from the outside, Accordingly, image light is sequentially emitted to perform image scanning, and image information is displayed on the display section A. [

Fig. 2 is a schematic view of the display portion A. Fig.

The display portion A has a wiring portion including a plurality of scanning lines 5 and data lines 6, a plurality of pixels 3, and the like on a substrate. The main components of the display portion A will be described below.

In the drawing, the light emitted by the pixel 3 is taken out in the white arrow direction (downward direction).

The scanning lines 5 and the plurality of data lines 6 of the wiring portion each include a conductive material and the scanning lines 5 and the data lines 6 are connected to the pixel 3 at orthogonal and orthogonal positions in a lattice form (Details not shown).

When a scanning signal is applied from the scanning line 5, the pixel 3 receives the image data signal from the data line 6 and emits light in accordance with the received image data.

Full-color display is possible by juxtaposing the pixel of the red color region, the pixel of the green color region and the pixel of the blue color region on the same substrate with appropriate color of light emission.

Next, the pixel light emission process will be described.

3 is a schematic diagram of a pixel.

The pixel includes an organic EL element 10, a switching transistor 11, a driving transistor 12, a capacitor 13, and the like. Full-color display can be performed by using organic EL elements emitting red, green, and blue as the organic EL elements 10 for a plurality of pixels and juxtaposing them on the same substrate.

3, an image data signal is applied from the control section B to the drain of the switching transistor 11 through the data line 6. [ When the scanning signal is applied from the control unit B to the gate of the switching transistor 11 through the scanning line 5, the driving of the switching transistor 11 is turned on and the image data signal applied to the drain is applied to the capacitor 13, And the gate of the driving transistor 12.

By the transfer of the image data signal, the capacitor 13 is charged in accordance with the potential of the image data signal, and the drive transistor 12 is turned on. The drain of the driving transistor 12 is connected to the power supply line 7 and the source thereof is connected to the electrode of the organic EL element 10 so that the driving transistor 12 is turned off from the power supply line 7 in accordance with the potential of the image data signal applied to the gate. Current is supplied to the EL element 10.

When the scanning signal is transferred to the next scanning line 5 by the progressive scanning of the control section B, the driving of the switching transistor 11 is turned off.

However, even if the driving of the switching transistor 11 is turned off, the capacitor 13 maintains the potential of the charged image data signal, so that the driving transistor 12 is kept in the ON state and the next scanning signal is applied The light emission of the organic EL element 10 continues.

When the next scanning signal is applied by progressive scanning, the driving transistor 12 is driven in accordance with the potential of the next image data signal in synchronization with the scanning signal, and the organic EL element 10 emits light.

That is, the light emission of the organic EL element 10 is performed by providing the switching transistor 11 and the driving transistor 12, which are active elements, to the organic EL element 10 of each of the plurality of pixels, The organic EL device 10 of the present invention emits light. Such a light emitting method is referred to as an active matrix method.

Here, the light emission of the organic EL element 10 may be a plurality of gradation light emission by a multi-level image data signal having a plurality of gradation levels, or may be on or off by a predetermined amount of light emission by a binary image data signal. The potential of the capacitor 13 may be maintained until the next scan signal is applied, or may be discharged immediately before the next scan signal is applied.

The present invention is not limited to the active matrix method described above, and may be a passive matrix type light emission driving method in which the organic EL element is caused to emit light in response to a data signal only when a scanning signal is scanned.

Fig. 4 is a schematic diagram of a display device according to the passive matrix method relating to the display portion A of Fig. 2; In Fig. 4, a plurality of scanning lines 5 and a plurality of image data lines 6 are provided in a lattice pattern so as to face each other with the pixel 3 interposed therebetween.

When the scanning signal of the scanning line 5 is applied by progressive scanning, the pixel 3 connected to the applied scanning line 5 emits light in accordance with the image data signal.

In the passive matrix system, there is no active element in the pixel 3, so that the manufacturing cost can be reduced.

&Quot; Lighting device &quot;

The lighting apparatus of the present invention will be described. The illumination device of the present invention comprises the organic EL device of the present invention.

The organic EL device of the present invention may be used as an organic EL device having a resonator structure. The light source of the optical storage medium, the light source of the electrophotographic copying machine, the light source of the optical communication processor, A light source of an optical sensor, and the like. However, the present invention is not limited thereto. It may also be used for the above-mentioned purposes by causing laser oscillation.

Further, the organic EL device of the present invention may be used as one kind of lamp such as an illumination light or an exposure light source, or may be a projection device of a type for projecting an image or a display device (display) of a type directly recognizing a still image or a moving image May be used.

The driving method when used as a display device for moving picture reproduction is either a simple matrix (passive matrix) method or an active matrix method. Alternatively, it is possible to manufacture a full color display device by using two or more kinds of the organic EL elements of the present invention having different luminescent colors.

Further, the organic EL material of the present invention is applicable to an organic EL device which generates substantially white light as an illumination device. A plurality of luminescent colors are simultaneously emitted by a plurality of luminescent materials to obtain white luminescence by mixing.

As a combination of a plurality of emission colors, three emission maximum wavelengths of three primary colors of blue, green and blue may be contained, and two emission maximum wavelengths using the relation of complementary colors such as blue and yellow, cyan and orange It is acceptable.

The combination of light-emitting materials for obtaining a plurality of light-emitting colors may be a combination of a plurality of materials that emit light in a plurality of phosphors or fluorescence, a light-emitting material that emits fluorescence or phosphorescence, and a light- And a coloring material may be used. In the white organic EL device according to the present invention, a plurality of luminescent dopants may be combined and mixed.

It is only necessary to arrange a mask only for forming a light emitting layer, a hole transporting layer, an electron transporting layer, or the like, and to divide it by a mask. An electrode film can be formed by a casting method, a spin coating method, an inkjet method, a printing method or the like, for example, and productivity is improved.

According to this method, the white organic EL device is different from the white organic EL device in which the light-emitting elements of a plurality of colors are arrayed in an array, and the element itself emits white light.

The luminescent material used for the luminescent layer is not particularly limited and may be a metal complex according to the present invention and a known luminescent material in order to be suitable for a wavelength range corresponding to CF (color filter) characteristics, for example, as a backlight in a liquid crystal display device. Any of the materials may be selectively combined to whiten.

&Quot; One form of illumination device of the present invention &quot;

One embodiment of the illumination device of the present invention including the organic EL device of the present invention will be described.

A non-light-emitting surface of the organic EL device of the present invention was covered with a glass case, a glass substrate having a thickness of 300 mu m was used as a sealing substrate, and an epoxy-based light curing type adhesive (Lux Track LC0629B manufactured by Toagosei Co., Ltd.) , And this is superimposed on the negative electrode to be in close contact with the transparent support substrate, and the glass substrate side is irradiated with UV light, cured, and sealed to form an illumination device as shown in Figs. 5 and 6. Fig.

5 shows a schematic diagram of a lighting device, and the organic EL element 101 of the present invention is covered with a glass cover 102 (sealing operation with a glass cover is performed by contacting the organic EL element 101 with air (In an atmosphere of a high-purity nitrogen gas having a purity of 99.999% or more) under a nitrogen atmosphere.

6 shows a cross-sectional view of the lighting apparatus. In Fig. 6, reference numeral 105 denotes a cathode, 106 denotes an organic EL layer, and 107 denotes a glass substrate with a transparent electrode (anode).

A nitrogen gas 108 is filled in the glass cover 102 and a catcher 109 is provided.

Hereinafter, the present invention will be described in detail by way of examples, but the present invention is not limited thereto.

The structures of the compounds used in Examples are shown below. Further, other compounds are described in the present specification.

Example 1

&Quot; Production of organic EL device 1-1 &

A substrate (NA45 manufactured by NH Technoglass Co., Ltd.) having a thickness of 100 nm formed of ITO (indium tin oxide) as an anode was patterned on a glass substrate having a size of 100 mm x 100 mm x 1.1 mm. The transparent support substrate provided with the ITO transparent electrode was coated with isopropyl Washed with ultrasonic waves with alcohol, dried with dry nitrogen gas, and subjected to UV ozone cleaning for 5 minutes.

Using a solution prepared by diluting poly (3,4-ethylenedioxythiophene) -polystyrenesulfonate (PEDOT / PSS, HC Stack, CLEVIO P VP AI 4083) with pure water to 70% on this transparent support substrate, A thin film was formed by spin coating at 3000 rpm for 30 seconds and then dried at 200 캜 for 1 hour to form a first hole transporting layer having a thickness of 20 nm.

The transparent support substrate was fixed to a substrate holder of a commercially available vacuum vapor deposition apparatus. On the other hand, a hole transport material 2 and a host compound 11-12 (same as the compound (1) described in WO2011 / 122132) were added to a molybdenum resistance heating boat. 200 mg of ET-8 as an electron transporting material was placed in a separate molybdenum resistance heating boat, and 100 mg of a compound (BD) as a dopant compound was put in a separate molybdenum resistance heating boat , And a vacuum deposition apparatus.

Subsequently, the vacuum tank was evacuated to 4 x 10 &lt; ^-4 &gt; Pa, and then the heating boat containing 11-12 was energized and heated to form a second hole transporting layer having a thickness of 20 nm on the first hole transporting layer at a deposition rate of 0.1 nm / .

Further, the heating boat containing the host compound 11-12 and the compound (BD) as the dopant compound was energized by heating and co-deposited on the second hole transport layer at deposition rates of 0.1 nm / sec and 0.025 nm / Thereby forming a light emitting layer having a thickness of 30 nm.

Further, the heating boat containing ET-8 was heated by electric power, and was deposited on the light emitting layer at a deposition rate of 0.1 nm / sec to form an electron transporting layer having a film thickness of 30 nm.

The substrate temperature at the time of vapor deposition was room temperature.

Subsequently, lithium fluoride was vapor-deposited to form a cathode buffer layer having a film thickness of 0.5 nm, and further aluminum was vapor-deposited to form a cathode having a thickness of 110 nm to produce a comparative organic EL device 1-1.

&Quot; Production of organic EL devices 1-2 to 1-14 &quot;

In the production of the organic EL device 1-1, the organic EL devices 1-2 to 1-n were formed in the same manner, except that the dopant compound of the luminescent layer and the compound 11-12 of the second hole transporting layer were changed to the compounds shown in Table 1. [ 1-14.

&Quot; Fabrication of organic EL device 1-15 &

In the production of the organic EL device 1-4, the organic EL device 1-15 was produced in the same manner as the host compound (H-1), except that the host of the light emitting layer was changed to the host compound (H-1).

&Quot; Evaluation of organic EL devices 1-1 to 1-15 &

When evaluating the obtained organic EL devices 1-1 to 1-15, the non-light emitting surfaces of the respective organic EL devices after fabrication were covered with a glass case, and a glass substrate having a thickness of 300 mu m was used as a sealing substrate, (Lux track LC0629B manufactured by Toagosei Co., Ltd.) was applied onto the above-mentioned negative electrode to be in close contact with the above-mentioned transparent support substrate, and UV light was irradiated on the glass substrate side to cure it and seal it. Figs. 5 and 6 An illumination device as shown in the figure was fabricated and evaluated.

Each sample thus produced was subjected to the following evaluations. The evaluation results are shown in Table 1.

(1) Quantum efficiency of external extraction (simply referred to as efficiency)

The organic EL device was lighted under a constant current condition of room temperature (about 23 to 25 ° C) and 2.5 mA / cm 2 to measure the light emission luminance L (cd / m 2) ?).

Here, the emission luminance was measured using CS-1000 (manufactured by Konica Minolta Sensing), and the external extraction quantum efficiency was expressed as a relative value with the organic EL element 1-1 as 100.

The larger the value, the higher the efficiency is.

(2) Half life

The half-life was evaluated according to the following measuring method.

Each organic EL device was driven at a constant current with a current giving an initial luminance of 1000 cd / m &lt; 2 &gt;, and the time for half of the initial luminance (500 cd / m &lt; 2 &gt;) was obtained.

The half-life was expressed as a relative value with the organic EL device 1-1 as 100. [

The larger the value, the longer life is preferable.

(3) Driving voltage

The voltage when the organic EL device was driven at a room temperature (about 23 DEG C to 25 DEG C) under a constant current condition of 2.5 mA / cm &lt; 2 &gt;

The smaller the value is, the lower the driving voltage is preferable.

It can be seen from Table 1 that the organic EL devices 1-4 and 1-7 to 1-15 of the present invention exhibit high luminous efficiency and high luminous efficiency for the organic EL devices 1-1 to 1-3, A long driving time, a low driving voltage, and an improved device characteristic. It can also be seen that the device characteristics are improved by making the HOMO level of the luminescent dopant and the adjacent layer-containing material to be in the relationship of the present invention.

Example 2

&Quot; Fabrication of organic EL elements 2-1 to 2-11 &quot;

The organic EL device 1-1 was prepared in the same manner as in the organic EL device 1-1 of Example 1 except for changing the dopant compound of the luminescent layer and the compound 11-12 of the second hole transporting layer to the compound shown in Table 2. [ 1 to 2-11.

&Quot; Production of organic EL device 2-12 &quot;

In the production of the organic EL device 2-5, the organic EL device 2-12 was produced in the same manner as the host compound (H-1) except that the host in the light emitting layer was changed to the host compound (H-1).

The obtained organic EL devices 2-1 to 2-12 were fabricated in the same manner as in Example 1 except that (1) external extraction quantum efficiency (simply referred to as efficiency), (2) half-life and (3) Respectively, and these values were expressed as relative values with the organic EL device 2-1 being set at 100, respectively.

It can be seen from Table 2 that the organic EL devices 2-5 and 2-8 to 2-12 of the present invention have higher luminous efficiency and higher luminous efficiency than the organic EL devices 2-1 to 2-4, 2-6 and 2-7 of the comparative example A long driving time, a low driving voltage, and an improved device characteristic. It can also be seen that the device characteristics are improved by setting the HOMO level of the material contained in the luminescent dopant and the adjacent layer to the relationship of the present invention.

Example 3

&Quot; Fabrication of organic EL elements 3-1 to 3-15 &quot;

The organic EL devices 3-1 to 3-3 were produced in the same manner as in the organic EL device 1-1 of Example 1 except that the dopant compound of the light emitting layer and the compound of the second hole transporting layer were changed to the compounds shown in Table 3. [ -15.

&Quot; Fabrication of organic EL element 3-16 &

In the production of the organic EL device 3-5, the organic EL device 3-16 was produced in the same manner as the host compound (H-1) except that the host in the emitting layer was changed to the host compound (H-1).

The obtained organic EL devices 3-1 to 3-16 were fabricated in the same manner as in Example 1 except that (1) external extraction quantum efficiency (simply referred to as efficiency), (2) half-life and (3) Respectively, and they were expressed as relative values, in which the organic EL element 3-1 was set to 100.

It can be seen from Table 3 that the organic EL devices 3-5 and 3-8 to 3-16 of the present invention have higher luminous efficiency and higher luminous efficiency than the organic EL devices 3-1 to 3-4, 3-6 and 3-7 of the comparative example It shows that the driving voltage is low and the characteristics as an element are improved. It can also be seen that the device characteristics are improved by making the HOMO level of the luminescent dopant and the adjacent layer-containing material to be in the relationship of the present invention.

Example 4

The organic EL devices 4-1 to 4-l were manufactured in the same manner as in the organic EL device 1-1 of Example 1 except that the dopant compound of the luminescent layer and the compound of the second hole transporting layer were changed to the compounds shown in Table 4. [ -19 were prepared.

The obtained organic EL devices 4-1 to 4-19 were fabricated in the same manner as in Example 1 except that (1) external extraction quantum efficiency (simply referred to as efficiency), (2) half-life and (3) Respectively, and these values were expressed as relative values with the organic EL element 4-1 set at 100. [

From Table 4, the organic EL devices 4-12 to 4-19 of the present invention exhibited higher luminous efficiency and longer life, respectively, as compared with the organic EL devices 4-1 to 4-11 of the comparative example, and the driving voltage was low, Is improved. It can also be seen that the device characteristics are improved by making the HOMO level of the luminescent dopant and the adjacent layer-containing material to be in the relationship of the present invention.

Example 5

&Quot; Production of white light-emitting organic EL device 5-1 &

A substrate (NA45 manufactured by NH Technoglass Co., Ltd.) having a thickness of 100 nm formed of ITO (indium tin oxide) as an anode was patterned on a glass substrate having a size of 100 mm x 100 mm x 1.1 mm. The transparent support substrate provided with the ITO transparent electrode was coated with isopropyl Washed with ultrasonic waves with alcohol, dried with dry nitrogen gas, and subjected to UV ozone cleaning for 5 minutes.

The transparent support substrate was fixed to a substrate holder of a commercially available vacuum vapor deposition apparatus. On the other hand, 200 mg of? -NPD as a hole transporting material was charged into a resistance heating boat made of molybdenum, and 11- 200 mg of a host compound (H-1) as a host compound was placed in a separate molybdenum resistance heating boat and 200 mg of ET-8 as an electron transporting material was placed in a separate molybdenum resistance heating boat, 100 mg of DP-1 as a dopant compound was placed in a resistive heating boat, and 100 mg of D-10 as a dopant compound was placed in a separate molybdenum resistance heating boat and installed in a vacuum evaporator.

Subsequently, the vacuum tank was reduced to 4 x 10 &lt; ^-4 &gt; Pa. Then, the heating boats in which alpha -NPD was introduced were separately energized and deposited on a transparent support substrate at a deposition rate of 0.1 nm / sec to form first holes To form a transport layer.

Further, the heating boat containing 11-12 was energized and heated to form a second hole transporting layer having a film thickness of 5 nm on the first hole transporting layer at a deposition rate of 0.05 nm / second, respectively.

The heating boat containing the host compound (H-1) as the host compound and DP-1 and D-10 as the dopant compound was energized and heated to adjust the deposition rate to 100: 5: 0.6, Thereby forming a light emitting layer having a thickness of 30 nm.

Further, the heating boat containing ET-8 was heated by electric power, and was deposited on the light emitting layer at a deposition rate of 0.1 nm / sec to form an electron transporting layer having a film thickness of 30 nm.

The substrate temperature at the time of vapor deposition was room temperature.

Subsequently, lithium fluoride was vapor-deposited to form a cathode buffer layer having a film thickness of 0.5 nm, and further aluminum was vapor-deposited to form a cathode having a film thickness of 110 nm to prepare an organic EL device 5-1.

When the produced organic EL device 5-1 was energized, almost white light was obtained and it was found that the device could be used as an illumination device.

&Quot; Production of organic EL elements 5-2 to 5-9 &quot;

Except that 11-12 used in the second hole transporting layer and dopant compound DP-1 used in the light emitting layer were changed to the compounds shown in Table 5 in the production of the organic EL device 5-1, 5-2 to 5-9, respectively. When the produced organic EL devices 5-2 to 5-9 were energized, almost white light was obtained and it was found that the device could be used as an illumination device.

Example 6

"Fabrication of organic EL full color display"

Fig. 7 shows a schematic configuration diagram of an organic EL full color display device.

After patterning with a pitch of 100 m on a substrate (NA45 manufactured by NH Techno Glass Co., Ltd.) on which a 100 nm thick ITO transparent electrode 202 was formed as an anode on a glass substrate 201 (see Fig. 7A) Barrier ribs 203 (20 占 퐉 width and 2.0 占 퐉 thickness) of non-photosensitive polyimide were formed by photolithography between the ITO transparent electrodes 202 on the transparent substrate 201 (see Fig. 7 (b)).

A hole injection layer composition of the following composition was injected between the partition walls 203 on the ITO transparent electrode 202 using an inkjet head (MJ800C, manufactured by Epson Corporation), irradiated with ultraviolet light for 200 seconds, The hole injection layer 204 having a film thickness of 40 nm was provided by drying treatment for 10 minutes (see Fig. 7 (c)).

The blue light emitting layer composition, the green light emitting layer composition and the red light emitting layer composition of the following compositions were ejected and injected onto the hole injection layer 204 using an ink jet head and dried at 60 DEG C for 10 minutes to form light emitting layers 205B , 205G, and 205R (see Fig. 7 (d)).

Subsequently, an electron transporting material (not shown) having a film thickness of 20 nm was deposited to cover the respective light emitting layers 205B, 205G, and 205R, and lithium fluoride was vapor deposited thereon to form a cathode buffer layer , And Al was vapor-deposited to form a cathode 206 having a film thickness of 130 nm to prepare an organic EL device (see FIG. 7 (e)).

The produced organic EL devices exhibited blue, green, and red luminescence respectively when a voltage was applied to the electrodes, and they were found to be usable as full color display devices.

(Hole injection layer composition)

11-12 20 parts by mass

50 parts by mass of cyclohexylbenzene

50 parts by mass of isopropyl biphenyl

(Blue light emitting layer composition)

Host compound (H-1) 0.7 part by mass Host

DP-1 0.04 parts by mass Dopant

50 parts by mass of cyclohexylbenzene

50 parts by mass of isopropyl biphenyl

(Green light emitting layer composition)

0.7 parts by mass of the host compound (H-1)

D-1 0.04 parts by mass

50 parts by mass of cyclohexylbenzene

50 parts by mass of isopropyl biphenyl

(Red light emitting layer composition)

0.7 parts by mass of the host compound (H-1)

D-10 0.04 parts by mass

50 parts by mass of cyclohexylbenzene

50 parts by mass of isopropyl biphenyl

1 display
3 pixels
5 scanning lines
6 data lines
7 power line
10 organic EL device
11 switching transistor
12 driving transistor
13 Condenser
101 organic EL device
102 Glass cover
105 cathode
106 organic EL layer
107 Glass substrate with transparent electrodes
108 nitrogen gas
109 catcher
201 glass substrate
202 ITO transparent electrode
203 barrier
204 Hole injection layer
205B, 205G, and 205R.
206 cathode
A display
B control section

Claims (13)

An organic electroluminescence element having a plurality of organic layers including at least one luminescent layer sandwiched between an anode and a cathode and an adjacent layer adjacent to an anode side of the luminescent layer,
Wherein at least one of the luminescent layers contains at least one phosphorescent luminescent dopant having a luminescence maximum wavelength at the shortest wavelength side of 470 nm and a HOMO value of -4.50 to -5.50 eV,
And a nonmetal complex compound represented by the following general formula (11) or (31), and having a HOMO value of -4.70 to -5.10 eV in the adjacent layer.
&Lt; Formula 11 >

(In the general formula (11), R ₁₁₁ and R ₁₁₂ represent a hydrogen atom, an alkyl group, an aromatic hydrocarbon ring group or an aromatic heterocyclic group, and the compound represented by the formula (11) may further have a substituent.)
(31)

(Wherein R ₃₁₁ and R ₃₁₂ represent a hydrogen atom, an arylsilyl group, an arylphosphoryl group, an aromatic hydrocarbon ring group, an aromatic heterocyclic group, a diarylamino group or an alkyl group, A ₁ to A ₈ each independently represents C -Rx or N, and a plurality of Rx's may be the same or different, and each Rx independently represents a hydrogen atom or a substituent. The method according to claim 1,
Wherein the phosphorescent luminescent dopant is a compound represented by the following chemical formula (41).
&Lt; EMI ID =

(Wherein M represents Ir, Pt, Rh, Ru, Ag or Cu, X ₁ and X ₂ represent a carbon atom or a nitrogen atom, and the ring Z ₁ together with C═C represents a 6-membered aromatic hydrocarbon Or a 5-membered or 6-membered aromatic heterocycle, and the ring Z ₂ , together with X ₁ -X ₂ , represents a 5-membered heterocyclic ring, L 'represents one of monoanionic two- Or m 'represents an integer of 0 to 2, n' is an integer of at least 1, and m '+ n' is 2 or 3.) 3. The method of claim 2,
In the compound represented by the above formula (41), the ring Z ₂ represents a substituted or unsubstituted imidazole ring. 3. The method of claim 2,
In the compound represented by the above formula (41), the ring Z ₂ represents a substituted or unsubstituted pyrazole ring. 3. The method of claim 2,
In the compound represented by the above formula (41), the ring Z ₂ represents a substituted or unsubstituted triazole ring. 3. The method according to claim 1 or 2,
Wherein the organic electroluminescence device is a white organic electroluminescent device. A lighting device comprising the organic electroluminescence device according to any one of claims 1 to 3. A display device comprising the organic electroluminescence device according to any one of claims 1 to 3. delete delete delete delete delete

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