JP2009182298A - Organic electroluminescence element, lighting device, and display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic electroluminescence element having high external quantum efficiency and long light-emission lifetime, and further to provide a lighting device and display device provided with the organic electroluminescence element. <P>SOLUTION: The organic electroluminescence element has at least an anode and a cathode on a supporting substrate, and has at least one light-emitting layer between the anode and the cathode, wherein the organic electroluminescence element includes, at least partially, a compound (compound A) having a saturated hydrocarbon ring or unsaturated hydrocarbon ring as a reaction group, and having a polymer (polymer A) in which the compound A is polymerized via the reaction group. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an organic electroluminescence element, a lighting device, and a display device.

  Conventionally, there is an electroluminescence display (ELD) as a light-emitting electronic display device. Examples of constituent elements of ELD include inorganic electroluminescent elements and organic electroluminescent elements (hereinafter also referred to as organic EL elements). Inorganic electroluminescent elements have been used as planar light sources, but an alternating high voltage is required to drive the light emitting elements.

  On the other hand, an organic EL device has a structure in which a light-emitting layer containing a light-emitting compound is sandwiched between a cathode and an anode, and excitons (excitons) are generated by injecting electrons and holes into the light-emitting layer and recombining them. The device emits light by utilizing the emission of light (fluorescence / phosphorescence) when the exciton is deactivated, and can emit light at a voltage of several volts to several tens of volts. Therefore, it has a wide viewing angle, high visibility, and since it is a thin-film type completely solid element, it has attracted attention from the viewpoints of space saving and portability.

  As the development of organic EL elements for practical use in the future, there is a demand for organic EL elements that emit light efficiently and with high luminance with lower power consumption. For example, in Japanese Patent No. 3093796, A technique for doping a stilbene derivative, a distyrylarylene derivative or a tristyrylarylene derivative with a small amount of a phosphor to improve emission luminance and prolong the lifetime of the device is disclosed in JP-A 63-264692. An element having an organic light-emitting layer in which an 8-hydroxyquinoline aluminum complex is used as a host compound and a small amount of phosphor is doped is disclosed. JP-A-3-255190 discloses an 8-hydroxyquinoline aluminum complex as a host. As a compound, an element having an organic light emitting layer doped with a quinacridone dye is known.

  In the technique disclosed in the above-mentioned patent document, when the emission from the excited singlet is used, the generation ratio of the singlet exciton and the triplet exciton is 1: 3, so the generation probability of the luminescent excited species is 25%. Since the light extraction efficiency is about 20%, the limit of the external extraction quantum efficiency (ηext) is set to 5%. However, M.M. A. Baldo et al. , Nature, 395, 151-154 (1998), since Princeton University reported on organic EL devices using phosphorescence emission from excited triplets. A. Baldo et al. , Nature, 403, 17, 750-753 (2000) and US Pat. No. 6,097,147, research on materials that exhibit phosphorescence at room temperature has become active.

  In addition, recently discovered organic EL devices that use phosphorescence can realize a luminous efficiency that is approximately four times that of previous devices that use fluorescence. Research and development of light-emitting element layer configurations and electrodes are performed all over the world. For example, S.M. Lamansky et al. , J .; Am. Chem. Soc. , 123, 4304 (2001), a number of compounds have been studied for synthesis centering on heavy metal complexes such as iridium complexes.

  In addition, the organic EL element is an all-solid element composed of an organic material film having a thickness of only about 0.1 μm between the electrodes, and can emit light at a relatively low voltage of about 2V to 20V. Therefore, it is a technology that is expected as a next-generation flat display and illumination.

  However, organic EL devices emit light in short wavelength regions such as blue and blue-green because the light emission mechanism is based on the light emission phenomenon utilizing the deactivation of organic materials from the excited state to the ground state. In order to achieve this, the band gap needs to be increased, and therefore a high voltage is required to excite the large gap.

  Furthermore, since the excited state itself is located at a high level, the damage when returning to the ground state is large, and the lifetime tends to be shorter than that of green or red light emission. In particular, phosphorescence utilizing light emission from the triplet excited state. The tendency becomes remarkable in light emission.

  There are various techniques as means for solving the above-mentioned problems. For example, there is a technique of increasing the molecular weight after forming a constituent layer of an organic electroluminescence element. A bifunctional triphenylamine derivative having two is described. After the compound is formed into a film, a three-dimensionally crosslinked polymer is formed by ultraviolet irradiation (see, for example, Patent Document 1). Two or more vinyls A technique of adding a group-containing material to a plurality of layers is disclosed, and a polymerization reaction is performed by irradiation with ultraviolet rays or heat at the time of forming an organic layer before laminating a cathode (for example, see Patent Document 2), phosphorescence Film formation by adding AIBN (azoisobutyronitrile), a radical generator, to a mixture of comonomer having a vinyl group in the same manner as a material having a vinyl group at the end of a luminescent dopant. Manufacturing method for promoting the polymerization reaction (e.g., see Patent Document 3), a manufacturing method of crosslinking by causing a Diels-Alder reaction between two molecules of the same layer (e.g., see Patent Document 4), and the like.

As described above, phosphorescent dopants, particularly phosphorescent dopants applicable to blue, have a very large band gap, can be used as a host for such dopants, achieve high luminous efficiency and long life simultaneously, Furthermore, a material applicable to the coating method (also referred to as a wet method) is not known.
Japanese Patent Laid-Open No. 5-271166 JP 2001-297882 A Japanese Patent Laid-Open No. 2003-73666 JP 2003-86371 A

  An object of the present invention is to provide an organic electroluminescence element having a high external extraction quantum efficiency and a long emission lifetime, and further providing an illumination device and a display device including the organic electroluminescence element.

  The above object of the present invention is achieved by the following configurations.

  1. A compound having a saturated hydrocarbon ring or an unsaturated hydrocarbon ring as a reactive group in an organic electroluminescence device having at least an anode and a cathode on a support substrate and having at least one light emitting layer between the anode and the cathode An organic electroluminescence device comprising (compound A) as a part and containing a polymer (polymer A) obtained by polymerizing the compound A via a reactive group.

  2. 2. The organic electroluminescence device according to 1 above, wherein the reactive group of the compound A is a cyclopropyl group or a cyclobutyl group.

  3. 3. The organic electroluminescence device according to 1 or 2, wherein the compound A is represented by the following general formula (a).

(In the formula, Ar _{1 to} Ar ₉ represent a hydrogen atom or an aromatic ring, and at least one of the aromatic rings is an aromatic ring substituted with a cyclopropyl group or a cyclobutyl group.)
4). 4. The organic electroluminescence device as described in 3 above, wherein there are at least two aromatic rings substituted with the cyclopropyl group or cyclobutyl group.

  5). 5. The organic electroluminescent element according to any one of 1 to 4, wherein the light emitting layer contains the compound A as at least a part and contains the polymer A.

  6). In any one of 1 to 5 above, wherein the light emitting layer contains the compound A as at least a part, contains the polymer A, and further contains a phosphorescent dopant. The organic electroluminescent element of description.

  7. 6. The organic electroluminescence device according to any one of 1 to 5, wherein the polymer A is a copolymer of the compound A and a phosphorescent dopant.

  8). 8. The organic electroluminescence device as described in 6 or 7 above, wherein the phosphorescent dopant is an Ir complex.

  9. 9. The organic electroluminescent device according to any one of 1 to 8, wherein the layer containing the compound A as at least a part and containing the polymer A is formed by a wet method.

  10. 10. The organic electroluminescence device according to any one of 1 to 9, wherein the compound A is polymerized after being applied.

  11. 11. The organic electroluminescent element according to any one of 1 to 10 above, which has a plurality of organic compound layers as a constituent layer.

  12 At least one anode buffer layer between the anode and the light emitting layer, or at least one cathode buffer layer between the cathode and the light emitting layer, wherein at least one of the light emitting layers is 12. The organic electroluminescence according to any one of 1 to 11, wherein the organic electroluminescence comprises at least a part of the compound A, the polymer A, and the light emitting layer formed by a wet method. element.

  13. The organic electroluminescence element according to any one of 1 to 12, which emits white light.

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

  15. 14. An illumination device comprising the organic electroluminescence element according to any one of 1 to 13 above.

  According to the present invention, an organic electroluminescence element having a high external extraction quantum efficiency and a long emission lifetime can be provided, and further, an illumination device and a display device including the organic electroluminescence element can be provided.

  In the organic electroluminescent element of this invention, it has the structure of any one of Claims 1-13, and can obtain an organic electroluminescent element with high external extraction quantum efficiency and long light emission lifetime. It was. Moreover, it succeeded also in obtaining the high-intensity display apparatus and illuminating device which comprised the said organic electroluminescent element.

  Hereinafter, details of each component according to the present invention will be sequentially described.

  As a result of various investigations on the above problems, the inventors of the present invention, in forming the constituent layers of the organic electroluminescence element, when laminating a plurality of functional layers, in order to apply and laminate the upper layer, the lower layer is completely resinized, It is necessary to coat and laminate the upper layer after forming a film having a high crosslinking density.

  Examples of highly reactive substituents used to form such high crosslink density films include, for example, cyclic ethers such as epoxy groups and oxetanes, but these substituents are cleaved from the ring. There is a problem that a hydroxy group is generated, and such a strong polar group adversely affects the lifetime of the device.

  Examples of the reactive group that does not generate a polar group include a vinyl group, but the solvent resistance to a coating solvent for a film obtained by converting the compound having the vinyl group into a resin was not sufficient.

  As a result of intensive studies by the present inventors on the improvement of solvent resistance to coating solvents, among reactive groups, a compound having a cyclopropyl group or a cyclobutyl group as a substituent of the functional compound according to the present invention or its weight It was found that a film having a very high crosslink density can be formed by using the coalescence.

  Furthermore, by using a compound having at least two reactive groups represented by a cyclopropyl group or a cyclobutyl group or a polymer of the compound according to the present invention, it has higher luminous efficiency and longer length than conventional organic EL devices. An element capable of simultaneously achieving the lifetime could be produced.

  Hereinafter, details of each component according to the present invention will be sequentially described.

<< Compound A, Polymer A >>
The compound A according to the present invention and the polymer A obtained by polymerizing the compound A will be described.

  In the present invention, the polymer A formed by polymerizing the compound A is only required to contain the compound A in a part of the polymer, and the compound A is polymerized via a reactive group (or polymerizable group). It is what you are doing.

  The compound A according to the present invention or the polymer A of the compound A can be prepared as a solution or a dispersion, and the film produced by coating is uniform and can be sufficiently used as an organic electroluminescence device.

  In addition, the compound A or the polymer A of the compound A has a sufficiently wide band gap that can be used as a host for a blue phosphorescent dopant, has high external extraction quantum efficiency, and has a long emission lifetime. A luminescence element can be provided, and further, an illumination device and a display device including the organic electroluminescence element can be provided.

  Compound A is most preferably a host compound in an organic electroluminescence device, but is used as a light emitting material in a light emitting layer, that is, a light emitting dopant, a hole injection material, a hole transport material, an electron injection material, and an electron transport material. May be.

  In the organic EL device of the present invention, the compound A may be incorporated in the device in the state of the compound A, that is, the state before polymerization (also referred to as a monomer or a monomer). It may be incorporated in the constituent layers.

  In particular, when the component layer of the element is formed by a wet method such as coating, for example, when the compound A is incorporated as a monomer when forming the light emitting layer, photopolymerization such as ultraviolet irradiation or thermal polymerization by heating. It is preferable to provide an electron transport layer or the like on the light emitting layer obtained by forming a polymer through the steps of performing the above and the like.

  On the other hand, it is also possible to incorporate the compound A according to the present invention into the constituent layer of the organic EL element of the present invention by vapor deposition or the like while maintaining the monomer (state before polymerization). In that case, after the organic EL element is formed, the compound A is polymerized by a polymerization reaction by active species generated by energization.

  It is also preferable to put a drying process before polymerization after preparing the coating film of compound A and before polymerization, for example, heating at a temperature slightly higher than the boiling point of the coating solvent. Moreover, after polymerizing the coating film, it is also preferable to add a process such as rinsing the polymer film with an appropriate solvent (which does not dissolve the polymer film) to remove insoluble materials, and further laminating and coating the upper layer.

  By using the element in this way, when the polymerization reaction proceeds, it is possible to obtain an effect of improving the characteristics of the element such as extending the light emission lifetime.

  The reactive group of the saturated hydrocarbon ring or unsaturated hydrocarbon ring in Compound A will be described.

  A saturated hydrocarbon ring is a cyclic molecule composed of carbon and hydrogen atoms. For example, a cycloalkyl group (for example, cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cyclooctyl group, cyclododecyl group, cyclotridecyl group) , Cyclotetradecyl group, cyclopentadecyl group, etc.), cycloalkenyl group (for example, cyclo-1-propenyl group, cyclo-2-propenyl group, cyclo-1-butenyl group, cyclo-2-butenyl group, cyclo-1 , 3-butadienyl group, cyclo-2-pentenyl group, isopropenyl group, etc.) and cycloalkynyl group (for example, ethynyl group, propargyl group, etc.).

  Examples of the reactive group of the saturated hydrocarbon ring or unsaturated hydrocarbon ring containing atoms other than carbon and hydrogen include a cycloalkoxy group (for example, cyclopentyloxy group, cyclohexyloxy group, etc.), a cycloalkylthio group (for example, A cyclopentylthio group, a cyclohexylthio group, etc.), a cyclohexylaminosulfonyl group, a cyclohexylcarbonyl group, a cyclohexylaminocarbonyl group, a cyclohexylureido group, and a cyclohexylsulfonyl group.

  These substituents may be further substituted with the above substituents. In addition, a plurality of these substituents may be bonded to each other to form a ring.

  Compound A is not particularly limited as long as it is a generally used organic EL device material having a reactive group having a saturated hydrocarbon ring or an unsaturated hydrocarbon ring, preferably a cyclopropyl group or a cyclobutyl group. It is only necessary to have a reactive group represented, and among them, a host compound in which a cyclopropyl group is substituted is most preferable.

  In the compound A having a reactive group represented by the cyclopropyl group or the cyclobutyl group, a preferable reactive group includes a cyclopropyl group. Moreover, it is preferable that the compound A has 2 or more reactive groups. When compound A has two or more reactive groups, the reactive groups may be the same or different.

In the general formula (a), examples of the aromatic ring represented by Ar _{1 to} Ar ₉ include an aromatic hydrocarbon ring and an aromatic heterocyclic ring. The aromatic ring may be a single ring or a condensed ring, and may be unsubstituted or may have a substituent as described later.

Examples of the aromatic hydrocarbon ring represented by Ar _{1 to} Ar ₉ 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, and an o-tell. Phenyl ring, m-terphenyl ring, p-terphenyl ring, acenaphthene ring, coronene ring, fluorene ring, fluoranthrene ring, naphthacene ring, pentacene ring, perylene ring, pentaphen ring, picene ring, pyrene ring, pyranthrene ring, Anthraanthrene rings and the like can be mentioned. These rings may further have a substituent.

Examples of the aromatic heterocycle represented by Ar _{1 to} Ar ₉ include a furan ring, a dibenzofuran ring, a thiophene ring, an oxazole ring, a pyrrole ring, a pyridine ring, a pyridazine ring, a pyrimidine ring, a pyrazine ring, a triazine ring, and a benzimidazole. Ring, oxadiazole ring, triazole ring, imidazole ring, pyrazole ring, thiazole ring, indazole ring, indazole ring, benzimidazole ring, benzothiazole ring, benzoxazole ring, quinoxaline ring, quinazoline ring, cinnoline ring, quinoline ring, isoquinoline Ring, phthalazine ring, naphthyridine ring, carbazole ring, carboline ring, diazacarbazole ring (showing a ring in which one of the carbon atoms of the hydrocarbon ring constituting the carboline ring is further substituted with a nitrogen atom).

Among these, in the general formula (a), the aromatic rings represented by Ar _{1 to} Ar ₉ are preferably carbazole rings, carboline rings, dibenzofuran rings, and benzene rings, and particularly preferably used. Carbazole ring, carboline ring, and benzene ring.

  Among the above, a benzene ring having a substituent is preferable, and a benzene ring having a carbazolyl machine is particularly preferable.

In the general formula (a), the aromatic rings represented by Ar _{1 to} Ar ₉ are each preferably a condensed ring having three or more rings as shown below, and the aromatic ring in which three or more rings are condensed. Specific examples of the aromatic hydrocarbon condensed ring include naphthacene ring, anthracene ring, tetracene ring, pentacene ring, hexacene ring, phenanthrene ring, pyrene ring, benzopyrene ring, benzoazulene ring, chrysene ring, benzochrysene ring, acenaphthene ring, Acenaphthylene ring, triphenylene ring, coronene ring, benzocoronene ring, hexabenzocoronene ring, fluorene ring, benzofluorene ring, fluoranthene ring, perylene ring, naphthperylene ring, pentabenzoperylene ring, benzoperylene ring, pentaphen ring, picene ring, pyranthrene ring , Coronene ring, naphtho coronene ring, ovalene ring Anse La entree down ring, and the like.

  Specific examples of the aromatic heterocycle condensed with three or more rings include an acridine ring, a benzoquinoline ring, a carbazole ring, a carboline ring, a phenazine ring, a phenanthridine ring, a phenanthroline ring, a carboline ring, a cyclazine ring, Kindin ring, tepenidine ring, quinindrin ring, triphenodithiazine ring, triphenodioxazine ring, phenanthrazine ring, anthrazine ring, perimidine ring, diazacarbazole ring (any one of the carbon atoms constituting the carboline ring is a nitrogen atom Phenanthroline ring, dibenzofuran ring, dibenzothiophene ring, naphthofuran ring, naphthothiophene ring, benzodifuran ring, benzodithiophene ring, naphthodifuran ring, naphthodithiophene ring, anthrafuran ring, anthradifuran ring, A Tiger thiophene ring, anthradithiophene ring, thianthrene ring, phenoxathiin ring, such as thio fan Tren ring (naphthaldehyde thiophene ring), and the like.

  The above rings may further have the following substituents.

  An alkyl group (for example, methyl group, ethyl group, propyl group, isopropyl group, t-butyl group, pentyl group, hexyl group, octyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, etc.), cycloalkyl group (for example, , Cyclopentyl group, cyclohexyl group, etc.), alkenyl group (for example, vinyl group, allyl group, 1-propenyl group, 2-butenyl group, 1,3-butadienyl group, 2-pentenyl group, isopropenyl group, etc.), alkynyl group (For example, ethynyl group, propargyl group, etc.), aromatic hydrocarbon group (also called aromatic carbocyclic group, aryl group, etc.), for example, phenyl group, p-chlorophenyl group, mesityl group, tolyl group, xylyl group, naphthyl group , Anthryl group, azulenyl group, acenaphthenyl group, fluorenyl group, phenanthryl group, Denyl group, pyrenyl group, biphenylyl group, etc.), aromatic heterocyclic group (for example, furyl group, thienyl group, pyridyl group, pyridazinyl group, pyrimidinyl group, pyrazinyl group, triazinyl group, imidazolyl group, pyrazolyl group, thiazolyl group, quinazolinyl group) Group, carbazolyl group, carbolinyl group, diazacarbazolyl group (in which one of the carbon atoms constituting the carboline ring of the carbolinyl group is replaced by a nitrogen atom), a phthalazinyl group, etc.), a heterocyclic group ( For example, pyrrolidyl group, imidazolidyl group, morpholyl group, oxazolidyl group, etc.), alkoxy group (for example, methoxy group, ethoxy group, propyloxy group, pentyloxy group, hexyloxy group, octyloxy group, dodecyloxy group, etc.), cyclo An alkoxy group (eg, cyclopentyl) Xy group, cyclohexyloxy group, etc.), aryloxy group (eg, phenoxy group, naphthyloxy group, etc.), alkylthio group (eg, methylthio group, ethylthio group, propylthio group, pentylthio group, hexylthio group, octylthio group, dodecylthio group, etc. ), Cycloalkylthio group (for example, cyclopentylthio group, cyclohexylthio group, etc.), arylthio group (for example, phenylthio group, naphthylthio group, etc.), alkoxycarbonyl group (for example, methyloxycarbonyl group, ethyloxycarbonyl group, butyloxycarbonyl) Group, octyloxycarbonyl group, dodecyloxycarbonyl group, etc.), aryloxycarbonyl group (eg, phenyloxycarbonyl group, naphthyloxycarbonyl group, etc.), sulfamoyl group (eg, acetyl group) Minosulfonyl group, methylaminosulfonyl group, dimethylaminosulfonyl group, butylaminosulfonyl group, hexylaminosulfonyl group, cyclohexylaminosulfonyl group, octylaminosulfonyl group, dodecylaminosulfonyl group, phenylaminosulfonyl group, naphthylaminosulfonyl group, 2 -Pyridylaminosulfonyl group, etc.), acyl groups (for example, acetyl group, ethylcarbonyl group, propylcarbonyl group, pentylcarbonyl group, cyclohexylcarbonyl group, octylcarbonyl group, 2-ethylhexylcarbonyl group, dodecylcarbonyl group, phenylcarbonyl group, naphthyl) Carbonyl group, pyridylcarbonyl group, etc.), acyloxy group (for example, acetyloxy group, ethylcarbonyloxy group, butylcarbonyloxy) Octylcarbonyloxy group, dodecylcarbonyloxy group, phenylcarbonyloxy group, etc.), amide group (for example, methylcarbonylamino group, ethylcarbonylamino group, dimethylcarbonylamino group, propylcarbonylamino group, pentylcarbonylamino group, cyclohexylcarbonyl) Amino group, 2-ethylhexylcarbonylamino group, octylcarbonylamino group, dodecylcarbonylamino group, phenylcarbonylamino group, naphthylcarbonylamino group, etc.), carbamoyl group (for example, aminocarbonyl group, methylaminocarbonyl group, dimethylaminocarbonyl group) Propylaminocarbonyl group, pentylaminocarbonyl group, cyclohexylaminocarbonyl group, octylaminocarbonyl group, 2-ethylhexyl Aminocarbonyl group, dodecylaminocarbonyl group, phenylaminocarbonyl group, naphthylaminocarbonyl group, 2-pyridylaminocarbonyl group, etc.), ureido group (for example, methylureido group, ethylureido group, pentylureido group, cyclohexylureido group, octylureido) Group, dodecylureido group, phenylureido group naphthylureido group, 2-pyridylaminoureido group, etc.), sulfinyl group (for example, methylsulfinyl group, ethylsulfinyl group, butylsulfinyl group, cyclohexylsulfinyl group, 2-ethylhexylsulfinyl group, dodecylsulfinyl group) Group, phenylsulfinyl group, naphthylsulfinyl group, 2-pyridylsulfinyl group, etc.), alkylsulfonyl group (for example, methylsulfonyl group, ethyl) Rusulfonyl group, butylsulfonyl group, cyclohexylsulfonyl group, 2-ethylhexylsulfonyl group, dodecylsulfonyl group, etc.), arylsulfonyl group or heteroarylsulfonyl group (for example, phenylsulfonyl group, naphthylsulfonyl group, 2-pyridylsulfonyl group, etc.) Amino group (for example, amino group, ethylamino group, dimethylamino group, butylamino group, cyclopentylamino group, 2-ethylhexylamino group, dodecylamino group, anilino group, naphthylamino group, 2-pyridylamino group), halogen Atom (for example, fluorine atom, chlorine atom, bromine atom, etc.), fluorinated hydrocarbon group (for example, fluoromethyl group, trifluoromethyl group, pentafluoroethyl group, pentafluorophenyl group, etc.), cyano group, nitro group, Hydro Shi group, a mercapto group, a silyl group (e.g., trimethylsilyl group, triisopropylsilyl group, triphenylsilyl group, a phenyl diethyl silyl group and the like), a phosphono group, and the like.

<< Polymer of compound having at least two aromatic rings substituted with cyclopropyl group or cyclobutyl group >>
The molecular weight (number average molecular weight (Mn), weight average molecular weight (Mw), molecular weight distribution (Mw / Mn), etc.) of the polymer of the compound having at least two cyclopropyl groups or cyclobutyl groups according to the present invention will be described.

  The molecular weight (weight average molecular weight Mw) of the polymer of the compound A according to the present invention is preferably 1,000,000 or less, more preferably 10,000 to 200,000. Furthermore, the ratio (molecular weight distribution) between the weight average molecular weight (Mw) and the number average molecular weight (Mn) according to the present invention is preferably 3 or less.

  The weight average molecular weight (Mw) and the number average molecular weight (Mn) of the polymer of the compound A according to the present invention are measured by GPC (gel permeation chromatography) using THF (tetrahydrofuran) as a column solvent. It can be carried out.

  Moreover, about the molecular weight of the polymer obtained by compound A being incorporated in the light emitting layer of the organic EL element in a state before polymerization, and then energizing the organic EL element, and polymerization proceeds in the light emitting layer. A layer containing only compound A is separately prepared in advance, and a plurality of samples (for example, about 10 samples) after photopolymerization in which the ultraviolet irradiation time is adjusted are prepared. The ultraviolet irradiation time and the molecular weight of the polymer (weight average, number) A calibration curve of (average molecular weight, etc.) is prepared in advance, and the molecular weight (weight average molecular weight, number average molecular weight or molecular weight distribution) can be determined from the ultraviolet irradiation time.

  On the other hand, the molecular weight of the polymer itself can be measured by a conventionally known method.

  Specifically, 1 ml of THF (using a degassed sample) is added to 1 mg of a measurement sample, and the sample is stirred using a magnetic stirrer at room temperature to be sufficiently dissolved. Subsequently, after processing with a membrane filter having a pore size of 0.45 to 0.50 μm, it is injected into a GPC (gel permeation chromatograph) apparatus.

  GPC measurement conditions are measured by stabilizing the column at 40 ° C., flowing THF (tetrahydrofuran) at a flow rate of 1 ml / min, and injecting about 100 μl of a sample having a concentration of 1 mg / ml.

  As the column, it is preferable to use a combination of commercially available polystyrene gel columns. For example, Shodex GPC KF-801, 802, 803, 804, 805, 806, 807 made by Showa Denko, TSKgel G1000H, G2000H, G3000H, G4000H, G5000H, G6000H, G7000H, TSK guard column made by Tosoh, etc. Etc. are preferred.

  As the detector, a refractive index detector (RI detector) or a UV detector is preferably used. In the measurement of the molecular weight of a sample, the molecular weight distribution of the sample is calculated using a calibration curve created using monodisperse polystyrene standard particles. About 10 points are preferably used as polystyrene for preparing a calibration curve. In the present invention, the molecular weight was measured under the following measurement conditions.

(Measurement condition)
Equipment: Tosoh High Speed GPC Equipment HLC-8220GPC
Column: TOSOH TSKgel Super HM-M
Detector: RI and / or UV
Eluent flow rate: 0.6 ml / min Sample concentration: 0.1% by mass
Sample volume: 100 μl
Calibration curve: produced with standard polystyrene: standard polystyrene STK standard polystyrene (manufactured by Tosoh Corporation) Mw = 100000 to 500-500 calibration curves (also called calibration curves) were prepared and used for the calculation of molecular weight. . It is preferable that the 13 samples are substantially equally spaced.

<< 0-0 transition band of compound A or polymer A of compound A >>
The compound A having at least two reactive groups represented by a cyclopropyl group or a cyclobutyl group according to the present invention or the polymer A of the compound A is used in any of the constituent layers of the organic EL device of the present invention described later. However, from the viewpoint of the effects described in the present invention (improvement of external extraction quantum efficiency, extension of emission lifetime), it is preferably contained in the organic compound layer described later. It is preferably contained in an electron transport layer, a hole transport layer, a hole blocking layer, an electron injection layer, or the like.

  Moreover, the compound whose phosphorescence 0-0 transition band of the compound A which concerns on this invention or the polymer A of a compound A is 460 nm or less is mentioned as a preferable compound. The method for measuring the 0-0 transition band will be described in detail in the light emitting dopant described later.

  Hereinafter, although the specific example of the compound A based on this invention is shown, this invention is not limited to these.

  The compound A according to the present invention and the polymer A of the compound A can be synthesized with reference to conventionally known documents and the like.

<< Constitutional layer of organic EL element, organic compound layer >>
The constituent layers and organic compound layers of the organic EL device of the present invention will be described. In this invention, although the preferable specific example of the layer structure of an organic EL element is shown below, this invention is not limited to these.

(I) Anode / light emitting layer / electron transport layer / cathode (ii) Anode / hole transport layer / light emitting layer / electron transport layer / cathode (iii) Anode / hole transport layer / light emitting layer / hole blocking layer / electron Transport layer / cathode (iv) Anode / hole transport layer / light emitting layer / hole blocking layer / electron transport layer / cathode buffer layer / cathode (v) Anode / anode buffer layer / hole transport layer / light emitting layer / hole Blocking layer / electron transport layer / cathode buffer layer / cathode << organic compound layer (also referred to as organic layer) >>
The organic compound layer according to the present invention will be described.

  The organic EL device of the present invention preferably has a plurality of organic compound layers as a constituent layer. Examples of the organic compound layer include a hole transport layer, a light emitting layer, and a hole blocking layer in the above layer constitution. In addition, an organic compound layer according to the present invention is defined as long as it contains an organic compound contained in a constituent layer of an organic EL element, such as a hole injection layer or an electron injection layer. Is done.

  Furthermore, when an organic compound is used for the anode buffer layer, the cathode buffer layer, and the like, the anode buffer layer, the cathode buffer layer, and the like each form an organic compound layer.

  The organic compound layer includes a layer containing “organic EL element material that can be used for a constituent layer of an organic EL element” or the like.

  In the organic EL device of the present invention, the blue light emitting layer preferably has an emission maximum wavelength of 430 to 480 nm, the green light emitting layer has an emission maximum wavelength of 510 to 550 nm, and the red light emitting layer has an emission maximum wavelength of 600 to 640 nm. A monochromatic light emitting layer in the range is preferable, and a display device using these is preferable. Alternatively, a white light emitting layer may be formed by laminating at least three light emitting layers. Further, a non-light emitting intermediate layer may be provided between the light emitting layers. The organic EL element of the present invention is preferably a white light emitting layer, and is preferably a lighting device using these.

  Each layer which comprises the organic EL element of this invention is demonstrated.

<Light emitting layer>
The light emitting layer according to the present invention is a layer that emits light by recombination of electrons and holes injected from the electrode, the electron transport layer, or the hole transport layer, and the light emitting portion is in the layer of the light emitting layer. May be the interface between the light emitting layer and the adjacent layer.

  The total film thickness of the light emitting layer is not particularly limited, but it is 2 nm to from the viewpoint of preventing the application of a high voltage unnecessary for the film homogeneity and light emission and improving the stability of the emission color with respect to the drive current. It is preferable to adjust to the range of 5 micrometers, More preferably, it adjusts to the range of 2-200 nm, Most preferably, it is the range of 10-20 nm.

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

  The light emitting layer of the organic EL device of the present invention preferably contains a light emitting host and at least one kind of light emitting dopant (phosphorescent dopant, fluorescent dopant, etc.).

《Host compound (also called luminescent host)》
The host compound used in the present invention will be described.

  Here, the host compound in the present invention is a phosphorescent quantum yield of phosphorescence emission at a room temperature (25 ° C.) having a mass ratio of 20% or more in the compound contained in the light emitting layer. Is defined as a compound of less than 0.1. The phosphorescence quantum yield is preferably less than 0.01. Moreover, it is preferable that the mass ratio in the layer is 20% or more among the compounds contained in a light emitting layer.

  As a host compound, you may use together the compound A based on this invention, the polymer A of this compound A, and also a well-known host compound.

  Further, by using a plurality of types of host compounds, it is possible to adjust the movement of charges, and the organic EL element can be made highly efficient. Moreover, it becomes possible to mix different light emission by using multiple types of light emission dopants mentioned later, and can thereby obtain arbitrary luminescent colors.

  The host compound used in the present invention may be a conventionally known low molecular compound or a high molecular compound having a repeating unit, and a low molecular compound having a polymerizable group such as a vinyl group or an epoxy group (deposition polymerization property). Light emitting host).

  A conventionally known host compound that may be used in combination is preferably a compound that has a hole transporting ability and an electron transporting ability, prevents the emission of light from becoming longer, and has a high Tg (glass transition temperature).

  Specific examples of conventionally known host compounds include compounds described in the following documents.

  JP-A-2001-257076, 2002-308855, 2001-313179, 2002-319491, 2001-357777, 2002-334786, 2002-8860, 2002-334787, 2002-15871, 2002-334788, 2002-43056, 2002-334789, 2002-75645, 2002-338579, 2002-105445 gazette, 2002-343568 gazette, 2002-141173 gazette, 2002-352957 gazette, 2002-203683 gazette, 2002-363227 gazette, 2002-231453 gazette, No. 003-3165, No. 2002-234888, No. 2003-27048, No. 2002-255934, No. 2002-260861, No. 2002-280183, No. 2002-299060, No. 2002. -302516, 2002-305083, 2002-305084, 2002-308837, and the like.

(Luminescent dopant)
The light emitting dopant according to the present invention will be described.

  As the light emitting dopant according to the present invention, a fluorescent dopant or a phosphorescent light emitting dopant can be used. From the viewpoint of obtaining an organic EL element with higher luminous efficiency, the light emitting layer or light emitting unit of the organic EL element of the present invention. As the luminescent dopant used in the above, it is preferable to contain the above-mentioned host compound and at the same time a phosphorescent dopant.

(Phosphorescent dopant)
The phosphorescent dopant according to the present invention will be described.

  The phosphorescent dopant according to the present invention is a compound in which light emission from an excited triplet is observed. Specifically, it is a compound that emits phosphorescence at room temperature (25 ° C.) and has a phosphorescence quantum yield. The phosphorescence quantum yield is preferably 0.1 or more, although it is defined as a compound of 0.01 or more at 25 ° C.

  The phosphorescence quantum yield can be measured by the method described in Spectroscopic II, page 398 (1992 edition, Maruzen) of Experimental Chemistry Course 4 of the 4th edition. Although the phosphorescence quantum yield in a solution can be measured using various solvents, the phosphorescence emitting dopant according to the present invention achieves the above phosphorescence quantum yield (0.01 or more) in any solvent. It only has to be done.

  There are two types of light emission of phosphorescent dopants in principle. One is the recombination of carriers on the host compound to which carriers are transported to generate an excited state of the host compound. Energy transfer type to obtain light emission from the phosphorescent dopant by moving to the phosphorescent dopant, the other is the phosphorescent dopant becomes a carrier trap, carrier recombination occurs on the phosphorescent dopant, There is a carrier trap type in which light emission from a phosphorescent dopant can be obtained.

  In any of the above cases, it is a condition that the excited state energy of the phosphorescent dopant is lower than the excited state energy of the host compound.

  The phosphorescent dopant can be appropriately selected from known materials used for the light emitting layer of the organic EL device.

  The phosphorescent dopant according to the present invention is preferably a complex compound containing a group 8-10 metal in the periodic table, more preferably an iridium compound (Ir complex), an osmium compound or a platinum compound (platinum). Complex-based compounds) and rare earth complexes, and most preferred are iridium compounds (Ir complexes).

  Although the specific example of the compound used as a phosphorescent dopant below is shown, this invention is not limited to these. These compounds are described, for example, in Inorg. Chem. 40, 1704-1711, and the like.

<< 0-0 transition band >>
The phosphorescent dopant according to the present invention preferably has a 0-0 transition band of phosphorescence wavelength of 485 nm or less.

(Measurement method of 0-0 transition band)
A method for measuring the 0-0 transition band of phosphorescence of the phosphorescent dopant according to the present invention will be described.

  First, a method for measuring a phosphorescence spectrum will be described.

  The compound to be measured (both phosphorescent dopant and host compound and other organic EL materials can be measured in the same manner) is well deoxygenated ethanol / methanol = 4/1 (vol / vol) It is dissolved in a solvent, put into a phosphorescence measurement cell, irradiated with excitation light at a liquid nitrogen temperature of 77 ° K, and an emission spectrum at 100 ms is measured after the excitation light irradiation. Since phosphorescence has a longer emission lifetime than fluorescence, it can be considered that light remaining after 100 ms is almost phosphorescence.

  For compounds with a phosphorescence lifetime shorter than 100 ms, measurement may be performed with a shorter delay time, but phosphorescence and fluorescence cannot be separated if the delay time is shortened so that it cannot be distinguished from fluorescence. Since this is a problem, it is necessary to select a delay time that can be separated.

  In addition, for a compound that cannot be dissolved in the solvent system, any solvent that can dissolve the compound may be used (substantially, the solvent effect of the phosphorescence wavelength is negligible in the above measurement method).

  Next, the 0-0 transition band is obtained. In the present invention, the emission maximum wavelength appearing on the shortest wavelength side in the phosphorescence spectrum chart obtained by the above measurement method is defined as the 0-0 transition band. To do.

  Since the phosphorescence spectrum usually has a low intensity, when it is enlarged, it may be difficult to distinguish between noise and peak. In such a case, the emission spectrum immediately after the excitation light irradiation (for convenience, this is called a steady light spectrum) is expanded, and the emission spectrum 100 ms after the excitation light irradiation (for convenience, this is called a phosphorescence spectrum) is superimposed. It can be determined by reading the peak wavelength from the portion of the steady light spectrum derived from the phosphorescence spectrum.

  Further, by performing a smoothing process on the phosphorescence spectrum, it is possible to separate the noise and the peak and read the peak wavelength. As the smoothing process, a smoothing method of Savitzky & Golay can be applied.

  The ionization potential (Ip) of the phosphorescent dopant according to the present invention is preferably 5.5 eV or less, more preferably 4.5 to 5.5 eV. Here, the ionization potential according to the present invention is defined by the energy required to emit electrons at the HOMO (highest occupied molecular orbital) level of the compound to the vacuum level, and specifically, the film state (layer) Energy) required to extract electrons from the compound in the (state), which can be directly measured by photoelectron spectroscopy. In the present invention, a value measured with an ESCA 5600 UPS (ultraviolet photoemission spectroscopy) manufactured by ULVAC-PHI Co., Ltd. is used.

  Hereinafter, although the specific example of the phosphorescence-emitting dopant which concerns on this invention is shown, this invention is not limited to these.

(Fluorescent dopant)
Fluorescent dopants include coumarin dyes, pyran dyes, cyanine dyes, croconium dyes, squalium dyes, oxobenzanthracene dyes, fluorescein dyes, rhodamine dyes, pyrylium dyes, perylene dyes, stilbene dyes , Polythiophene dyes, or rare earth complex phosphors.

  Next, an injection layer, a blocking layer, an electron transport layer, and the like used as a constituent layer of the organic EL element of the present invention will be described.

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

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

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

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

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

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

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

  The hole blocking layer may contain the compound A according to the present invention mentioned as the host compound or the polymer A of the compound A.

  Further, in the present invention, when a plurality of light emitting layers having different light emission colors are provided, it is preferable that the light emitting layer whose emission maximum wavelength is the shortest is the closest to the anode among all the light emitting layers. In this case, it is preferable that a hole blocking layer is additionally provided between the shortest wave layer and the light emitting layer next to the anode next to the shortest wave layer. Furthermore, it is preferable that 50% by mass or more of the compound contained in the hole blocking layer provided at the position has an ionization potential of 0.3 eV or more larger than the host compound of the shortest wave emitting layer.

  The ionization potential is defined by the energy required to emit electrons at the HOMO (highest occupied molecular orbital) level of the compound to the vacuum level, and can be determined by, for example, the following method.

  (1) Using Gaussian 98 (Gaussian 98, Revision A.11.4, MJ Frisch, et al., Gaussian, Inc., Pittsburgh PA, 2002.), a molecular orbital calculation software manufactured by Gaussian, USA. The ionization potential can be obtained as a value obtained by rounding off the second decimal place of the value (eV unit converted value) calculated by performing structural optimization using B3LYP / 6-31G *. This calculation value is effective because the correlation between the calculation value obtained by this method and the experimental value is high.

  (2) The ionization potential can also be obtained by a method of directly measuring by photoelectron spectroscopy. For example, a method known as ultraviolet photoelectron spectroscopy can be suitably used using a low energy electron spectrometer “Model AC-1” manufactured by Riken Keiki.

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

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

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

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

  Representative examples of aromatic tertiary amine compounds and styrylamine compounds include N, N, N ', N'-tetraphenyl-4,4'-diaminophenyl; N, N'-diphenyl-N, N'- Bis (3-methylphenyl)-[1,1'-biphenyl] -4,4'-diamine (TPD); 2,2-bis (4-di-p-tolylaminophenyl) propane; 1,1-bis (4-di-p-tolylaminophenyl) cyclohexane; N, N, N ′, N′-tetra-p-tolyl-4,4′-diaminobiphenyl; 1,1-bis (4-di-p-tolyl) Aminophenyl) -4-phenylcyclohexane; bis (4-dimethylamino-2-methylphenyl) phenylmethane; bis (4-di-p-tolylaminophenyl) phenylmethane; N, N'-diphenyl-N, N ' − (4-methoxyphenyl) -4,4'-diaminobiphenyl; N, N, N ', N'-tetraphenyl-4,4'-diaminodiphenyl ether; 4,4'-bis (diphenylamino) quadriphenyl; N, N, N-tri (p-tolyl) amine; 4- (di-p-tolylamino) -4 '-[4- (di-p-tolylamino) styryl] stilbene; 4-N, N-diphenylamino- (2-diphenylvinyl) benzene; 3-methoxy-4′-N, N-diphenylaminostilbenzene; N-phenylcarbazole, and also two of those described in US Pat. No. 5,061,569. Having a condensed aromatic ring in the molecule, for example, 4,4'-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (NPD), JP-A-4-3086 4,4 ', 4 "-tris [N- (3-methylphenyl) -N-phenylamino] triphenylamine in which three triphenylamine units described in Japanese Patent No. 8 are linked in a starburst type ( MTDATA) and the like.

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

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

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

  Alternatively, a hole transport layer having a high p property doped with impurities can be used. Examples thereof include JP-A-4-297076, JP-A-2000-196140, and JP-A-2001-102175; Appl. Phys. 95, 5773 (2004), and the like.

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

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

  Conventionally, in the case of a single electron transport layer and a plurality of layers, an electron transport material (also serving as a hole blocking material) used for an electron transport layer adjacent to the cathode side with respect to the light emitting layer is injected from the cathode. Any material may be used as long as it has a function of transferring electrons to the light-emitting layer, and any material can be selected from conventionally known compounds.

  Examples include nitro-substituted fluorene derivatives, diphenylquinone derivatives, thiopyran dioxide derivatives, carbodiimides, fluorenylidenemethane derivatives, anthraquinodimethane and anthrone derivatives, oxadiazole derivatives, and the like.

  Furthermore, in the above oxadiazole derivative, a thiadiazole derivative in which the oxygen atom of the oxadiazole ring is substituted with a sulfur atom, and a quinoxaline derivative having a quinoxaline ring known as an electron withdrawing group can also be used as an electron transport material. Furthermore, a polymer material in which these materials are introduced into a polymer chain or these materials are used as a polymer main chain can also be used.

  In addition, metal complexes of 8-quinolinol derivatives such as tris (8-quinolinol) aluminum (Alq), tris (5,7-dichloro-8-quinolinol) aluminum, tris (5,7-dibromo-8-quinolinol) aluminum. Tris (2-methyl-8-quinolinol) aluminum, tris (5-methyl-8-quinolinol) aluminum, bis (8-quinolinol) zinc (Znq), and the like, and the central metals of these metal complexes are In, Mg, Metal complexes replaced with Cu, Ca, Sn, Ga or Pb can also be used as the electron transport material.

  In addition, metal-free or metal phthalocyanine, or those having terminal ends substituted with an alkyl group or a sulfonic acid group can be preferably used as the electron transporting material. In addition, the distyrylpyrazine derivative exemplified as the material of the light emitting layer can also be used as an electron transport material, and an inorganic semiconductor such as n-type-Si, n-type-SiC, etc. as in the case of the hole injection layer and hole transport layer Can also be used as an electron transporting material.

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

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

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

"anode"
As the anode in the organic EL element, an electrode material made of a metal, an alloy, an electrically conductive compound, or a mixture thereof having a high work function (4 eV or more) is preferably used.

Specific examples of such electrode substances include metals such as Au, and conductive transparent materials such as CuI, indium tin oxide (ITO), SnO ₂ , and ZnO.

Alternatively, an amorphous material such as IDIXO (In ₂ O ₃ —ZnO) capable of forming a transparent conductive film may be used. For the anode, these electrode materials may be formed into a thin film by a method such as vapor deposition or sputtering, and a pattern having a desired shape may be formed by a photolithography method, or when pattern accuracy is not so high (about 100 μm or more) A pattern may be formed through a mask having a desired shape at the time of vapor deposition or sputtering of the electrode material.

  Or when using the substance which can be apply | coated like an organic electroconductivity compound, wet film-forming methods, such as a printing system and a coating system, can also be used. When light emission is extracted from the anode, it is desirable that the transmittance be greater than 10%, and the sheet resistance as the anode is preferably several hundred Ω / □ or less. Further, although the film thickness depends on the material, it is usually selected in the range of 10 to 1000 nm, preferably 10 to 200 nm.

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

Among these, from the point of durability against electron injection and oxidation, etc., a mixture of an electron injecting metal and a second metal which is a stable metal having a larger work function than this, for example, a magnesium / silver mixture, Suitable are 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. The cathode can be produced by forming a thin film of these electrode materials by a method such as vapor deposition or sputtering.

  The sheet resistance as the cathode is preferably several hundred Ω / □ or less, and the film thickness is usually selected in the range of 10 nm to 5 μm, preferably 50 to 200 nm. In order to transmit the emitted light, if either the anode or the cathode of the organic EL element is transparent or translucent, the light emission luminance is improved, which is convenient.

  Moreover, after producing the said metal with a film thickness of 1-20 nm on a cathode, a transparent or semi-transparent cathode can be produced by producing the electroconductive transparent material quoted by description of the anode on it, By applying this, an element in which both the anode and the cathode are transmissive can be manufactured.

《Support substrate》
As a support substrate (hereinafter also referred to as a substrate, substrate, substrate, support, etc.) that can be used in the organic EL device of the present invention, there is no particular limitation on the type of glass, plastic, etc., and it is transparent. May be opaque. When extracting light from the support substrate side, the support substrate is preferably transparent. Examples of the transparent support substrate preferably used include glass, quartz, and a transparent resin film. A particularly preferable support substrate is a resin film capable of giving flexibility to the organic EL element.

  Examples of the resin film include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyethylene, polypropylene, cellophane, cellulose diacetate, cellulose triacetate, cellulose acetate butyrate, cellulose acetate propionate (CAP), Cellulose esters such as cellulose acetate phthalate (TAC) and cellulose nitrate or derivatives thereof, polyvinylidene chloride, polyvinyl alcohol, polyethylene vinyl alcohol, syndiotactic polystyrene, polycarbonate, norbornene resin, polymethylpentene, polyether ketone, polyimide , Polyethersulfone (PES), polyphenylene sulfide, polysulfones Polyetherimide, polyether ketone imide, polyamide, fluorine resin, nylon, polymethyl methacrylate, acrylic or polyarylates, and cycloolefin resins such as ARTON (manufactured by JSR) or APEL (manufactured by Mitsui Chemicals).

On the surface of the resin film, an inorganic film, an organic film, or a hybrid film of both may be formed. Water vapor permeability (25 ± 0.5 ° C.) measured by a method according to JIS K 7129-1992. , Relative humidity (90 ± 2)% RH) is preferably 0.01 g / (m ² · 24 h) or less, and more preferably oxygen permeability measured by a method according to JIS K 7126-1987. A high barrier property film having a degree of 10 ⁻³ ml / (m ² · 24 hr · MPa) or less and a water vapor permeability of 10 ⁻⁵ g / (m ² · 24 h) or less is preferable.

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

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

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

  The external extraction efficiency at room temperature of light emission of the organic EL device of the present invention is preferably 1% or more, more preferably 5% or more. Here, the external extraction quantum efficiency (%) = the number of photons emitted to the outside of the organic EL element / the number of electrons sent to the organic EL element × 100.

  In addition, a hue improvement filter such as a color filter may be used in combination, or a color conversion filter that converts the emission color from the organic EL element into multiple colors using a phosphor. In the case of using a color conversion filter, the λmax of light emission of the organic EL element is preferably 480 nm or less.

<Sealing>
As a sealing means used for this invention, the method of adhere | attaching a sealing member, an electrode, and a support substrate with an adhesive agent can be mentioned, for example.

  As a sealing member, it should just be arrange | positioned so that the display area | region of an organic EL element may be covered, and concave plate shape or flat plate shape may be sufficient. Further, transparency and electrical insulation are not particularly limited.

  Specific examples include a glass plate, a polymer plate / film, and a metal plate / film. Examples of the glass plate include soda-lime glass, barium / strontium-containing glass, lead glass, aluminosilicate glass, borosilicate glass, barium borosilicate glass, and quartz. Examples of the polymer plate include polycarbonate, acrylic, polyethylene terephthalate, polyether sulfide, and polysulfone. Examples of the metal plate include those made of one or more metals or alloys selected from the group consisting of stainless steel, iron, copper, aluminum, magnesium, nickel, zinc, chromium, titanium, molybdenum, silicon, germanium, and tantalum.

In the present invention, a polymer film and a metal film can be preferably used because the element can be thinned. Further, the polymer film has an oxygen permeability measured by a method according to JIS K 7126-1987 of 1 × 10 ⁻³ ml / (m ² · 24 hr · MPa) or less and a method according to JIS K 7129-1992. The measured water vapor permeability (25 ± 0.5 ° C., relative humidity (90 ± 2)% RH) is preferably 1 × 10 ⁻³ g / (m ² · 24 h) or less.

  For processing the sealing member into a concave shape, sandblasting, chemical etching, or the like is used.

  Specific examples of the adhesive include photocuring and thermosetting adhesives having reactive vinyl groups such as acrylic acid oligomers and methacrylic acid oligomers, and moisture curing adhesives such as 2-cyanoacrylates. be able to. Moreover, heat | fever and chemical curing types (two-component mixing), such as an epoxy type, can be mentioned. Moreover, hot-melt type polyamide, polyester, and polyolefin can be mentioned. Moreover, a cationic curing type ultraviolet curing epoxy resin adhesive can be mentioned.

  In addition, since an organic EL element may deteriorate by heat processing, what can be adhesive-hardened from room temperature to 80 degreeC is preferable. A desiccant may be dispersed in the adhesive. Application | coating of the adhesive agent to a sealing part may use commercially available dispenser, and may print like screen printing.

  In addition, it is also preferable that the electrode and the organic layer are coated on the outside of the electrode facing the support substrate with the organic layer interposed therebetween, and an inorganic or organic layer is formed in contact with the support substrate to form a sealing film. . In this case, the material for forming the film may be any material that has a function of suppressing intrusion of elements that cause deterioration of elements such as moisture and oxygen. For example, silicon oxide, silicon dioxide, silicon nitride, or the like may be used. it can.

  Further, in order to improve the brittleness of the film, it is preferable to have a laminated structure of these inorganic layers and layers made of organic materials. The method for forming these films is not particularly limited. For example, vacuum deposition method, sputtering method, reactive sputtering method, molecular beam epitaxy method, cluster ion beam method, ion plating method, plasma polymerization method, atmospheric pressure plasma A polymerization method, a plasma CVD method, a laser CVD method, a thermal CVD method, a coating method, or the like can be used.

  In the gap between the sealing member and the display area of the organic EL element, an inert gas such as nitrogen or argon, or an inert liquid such as fluorinated hydrocarbon or silicon oil can be injected in the gas phase and liquid phase. preferable. A vacuum can also be used. Moreover, a hygroscopic compound can also be enclosed inside.

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

《Protective film, protective plate》
In order to increase the mechanical strength of the element, a protective film or a protective plate may be provided on the outer side of the sealing film on the side facing the support substrate with the organic layer interposed therebetween or on the sealing film. In particular, when the sealing is performed by the sealing film, the mechanical strength is not necessarily high, and thus it is preferable to provide such a protective film and a protective plate. As a material that can be used for this, the same glass plate, polymer plate / film, metal plate / film, and the like used for the sealing can be used, but the polymer film is light and thin. Is preferably used.

《Light extraction》
An organic EL element emits light inside a layer having a refractive index higher than that of air (refractive index is about 1.7 to 2.1), and only about 15% to 20% of light generated in the light emitting layer can be extracted. It is generally said. This is because light incident on the interface (interface between the transparent substrate and air) at an angle θ greater than the critical angle causes total reflection and cannot be taken out of the device, or between the transparent electrode or light emitting layer and the transparent substrate. This is because the light is totally reflected between the light and the light is guided through the transparent electrode or the light emitting layer, and as a result, the light escapes in the direction of the element side surface.

  As a method of improving the light extraction efficiency, for example, a method of forming irregularities on the surface of the transparent substrate and preventing total reflection at the transparent substrate and the air interface (US Pat. No. 4,774,435), A method of improving efficiency by providing a light collecting property to a substrate (Japanese Patent Laid-Open No. 63-314795), a method of forming a reflective surface on a side surface of an element (Japanese Patent Laid-Open No. 1-220394), and light emission from a substrate A method of forming an antireflection film by introducing a flat layer having an intermediate refractive index between the bodies (Japanese Patent Laid-Open No. 62-172691), a flat having a lower refractive index between the substrate and the light emitter than the substrate A method of introducing a layer (Japanese Patent Laid-Open No. 2001-202827), a method of forming a diffraction grating between any one of a substrate, a transparent electrode layer and a light emitting layer (including between the substrate and the outside) (Japanese Patent Laid-Open No. 11-283951) Gazette).

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

  When a medium having a low refractive index is formed between the transparent electrode and the transparent substrate with a thickness longer than the wavelength of light, the light extracted from the transparent electrode has a higher extraction efficiency to the outside as the refractive index of the medium is lower.

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

  The thickness of the low refractive index medium is preferably at least twice the wavelength in the medium. This is because the effect of the low refractive index layer is diminished when the thickness of the low refractive index medium is about the wavelength of light and the electromagnetic wave that has exuded by evanescent enters the substrate.

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

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

  As described above, the position where the diffraction grating is introduced may be in any of the layers or in the medium (in the transparent substrate or in the transparent electrode), but is preferably in the vicinity of the organic light emitting layer where light is generated. At this time, the period of the diffraction grating is preferably about 1/2 to 3 times the wavelength of light in the medium. The arrangement of the diffraction grating is preferably two-dimensionally repeated, such as a square lattice, a triangular lattice, or a honeycomb lattice.

《Condensing sheet》
The organic EL device of the present invention is processed on the light extraction side of the substrate so as to provide, for example, a microlens array structure, or combined with a so-called condensing sheet, for example, with respect to a specific direction, for example, the device light emitting surface. By condensing in the front direction, the luminance in a specific direction can be increased.

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

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

  Moreover, in order to control the light emission angle from a light emitting element, you may use together a light diffusing plate and a film with a condensing sheet. For example, a diffusion film (light-up) manufactured by Kimoto Co., Ltd. can be used.

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

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

  As a method for forming each of these layers, there are a vapor deposition method, a wet process (spin coating method, casting method, ink jet method, printing method) and the like as described above, but it is easy to obtain a homogeneous film and it is difficult to generate pinholes. In view of the above, film formation by a coating method such as a spin coating method, an ink jet method, or a printing method is preferable in the present invention.

  Examples of the liquid medium for dissolving or dispersing the organic EL material according to the present invention include ketones such as methyl ethyl ketone and cyclohexanone, fatty acid esters such as ethyl acetate, halogenated hydrocarbons such as dichlorobenzene, toluene, xylene, and mesitylene. Aromatic hydrocarbons such as cyclohexylbenzene, aliphatic hydrocarbons such as cyclohexane, decalin, and dodecane, and organic solvents such as DMF and DMSO can be used. Moreover, as a dispersion method, it can disperse | distribute by dispersion methods, such as an ultrasonic wave, high shear force dispersion | distribution, and media dispersion | distribution.

  After these layers are formed, a thin film made of a cathode material is formed thereon by a method such as vapor deposition or sputtering so as to have a film thickness of 1 μm or less, preferably 50 to 200 nm, and a cathode is provided. Thus, a desired organic EL element can be obtained.

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

<Application>
The organic EL element of the present invention can be used as a display device, a display, and various light emission sources. For example, lighting devices (home lighting, interior lighting), clock and liquid crystal backlights, billboard advertisements, traffic lights, light sources of optical storage media, light sources of electrophotographic copying machines, light sources of optical communication processors, light Although the light source of a sensor etc. are mentioned, It is not limited to this, Especially, it can use effectively for the use as a backlight of a liquid crystal display device, and a light source for illumination.

  In the organic EL element of the present invention, patterning may be performed by a metal mask, an ink jet printing method, or the like as needed during film formation. In the case of patterning, only the electrode may be patterned, the electrode and the light emitting layer may be patterned, or the entire layer of the element may be patterned, and a conventionally known method may be used in the fabrication of the element. it can.

  The light emission color of the organic EL device of the present invention and the compound according to the present invention is shown in FIG. 4.16 on page 108 of “New Color Science Handbook” (edited by the Japan Color Society, University of Tokyo Press, 1985). It is determined by the color when the result measured with the total CS-1000 (manufactured by Konica Minolta Sensing) is applied to the CIE chromaticity coordinates.

When the organic EL element of the present invention is a white element, white means that the chromaticity in the CIE1931 color system at 1000 cd / m ² is X when the 2 ° viewing angle front luminance is measured by the above method. = 0.33 ± 0.07 and Y = 0.33 ± 0.1.

  EXAMPLES Hereinafter, although an Example demonstrates this invention, the embodiment of this invention is not limited to these.

Example 1
<< Production of Organic EL Element 1-1 >>
A transparent substrate provided with this ITO transparent electrode after patterning was performed on a substrate (NH-Technoglass NA-45) obtained by forming a 100 nm film of ITO (indium tin oxide) on a 100 mm × 100 mm × 1.1 mm glass substrate as an anode. The supporting substrate was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and UV ozone cleaning was performed for 5 minutes.

  On this transparent support substrate, a solution obtained by diluting poly (3,4-ethylenedioxythiophene) -polystyrene sulfonate (PEDOT / PSS, Bayer, Baytron P Al 4083) to 70% with pure water at 3000 rpm for 30 seconds. After forming into a film by the spin coat method, it dried at 200 degreeC for 1 hour, and provided the 1st positive hole transport layer with a film thickness of 30 nm.

Transferring the substrate to a nitrogen atmosphere, the first hole transporting layer, was formed 1000rpm a solution of Compound A ₀ of 50mg of toluene 10 ml, 30 seconds under the conditions of, by spin coating. Ultraviolet light was irradiated for 180 seconds, photopolymerization and crosslinking were performed, and a second hole transport layer having a thickness of about 25 nm was obtained.

  On this second hole transport layer, a solution of 100 mg of Comparative Compound 1 and 10 mg of Ir-11 dissolved in 10 ml of toluene was formed by spin coating under conditions of 1000 rpm and 30 seconds. Ultraviolet light was irradiated for 15 seconds, photopolymerization / crosslinking was performed, and heating was further performed in vacuum at 150 ° C. for 1 hour to obtain a light emitting layer having a film thickness of about 50 nm.

  Next, a solution obtained by dissolving 50 mg of tBu-PBD in 10 ml of toluene was formed on this light emitting layer by spin coating at 1000 rpm for 30 seconds, and vacuum-dried at 60 ° C. for 1 hour. The electron transport layer was 25 nm.

This is attached to a vacuum deposition apparatus, and then the vacuum chamber is decompressed to 4 × 10 ⁻⁴ Pa, lithium fluoride 1.0 nm is deposited as a cathode buffer layer, and aluminum 110 nm is deposited as a cathode to form a cathode, and an organic EL device 1-1 was produced.

<< Production of Organic EL Elements 1-2 to 1-8 >>
In the production of the organic EL element 1-1, organic EL elements 1-2 to 1-8 were respectively produced in the same manner except that the compounds shown in Table 1 were used instead of the comparative compound 1 and tBu-PBD.

<< Evaluation of organic EL elements >>
About the obtained organic EL elements 1-1 to 1-8, the external extraction quantum efficiency and the light emission lifetime were evaluated as follows.

<< External quantum efficiency >>
About the produced organic EL element, the external extraction quantum efficiency (%) when a ^2.5 mA / cm ² constant current was applied in a dry nitrogen gas atmosphere at 23 ° C. was measured. For the measurement, a spectral radiance meter CS-1000 (manufactured by Konica Minolta Sensing) was used. The obtained results are shown in Table 1. The measurement result of the external extraction quantum efficiency was expressed as a relative value when the measurement value of the organic EL element 1-1 was 100.

<Luminescent life>
When driving at a constant current of ^2.5 mA / cm ² , the time required for the luminance to drop to half of the luminance immediately after the start of light emission (initial luminance) was measured, and this was calculated as the half-life time (τ ^1/2 ) As an index of life.

  For the measurement, a spectral radiance meter CS-1000 (manufactured by Konica Minolta Sensing) was used. The obtained results are shown in Table 1. In addition, the measurement result of the light emission lifetime of Table 1 was represented by the relative value when the organic EL element 1-1 was set to 100.

  From Table 1, compared with the comparative organic EL elements 1-1 and 1-2, each of the organic EL elements 1-3 to 1-8 of the present invention exhibits remarkably good characteristics in both external extraction quantum efficiency and emission lifetime. I understand that. Each of the organic EL elements 1-3 to 1-8 of the present invention can be laminated by a coating method because an organic thin film having a high crosslinking resistance and a crosslinking density can be formed. In terms of device performance, it was possible to obtain a device having a high emission efficiency and a long emission lifetime.

Example 2
<< Production of organic EL full-color display device >>
FIG. 1 shows a schematic configuration diagram of an organic EL full-color display device. After patterning at a pitch of 100 μm on a substrate (NH45 made of NH technoglass) having a 100 nm ITO transparent electrode (102) formed on a glass substrate 101 as an anode, non-photosensitive between the ITO transparent electrodes on this glass substrate A partition 103 made of conductive polyimide (width 20 μm, thickness 2.0 μm) was formed by photolithography. A hole injection layer composition having the following composition is ejected and injected between polyimide partition walls on the ITO electrode using an inkjet head (manufactured by Epson; MJ800C), irradiated with ultraviolet light for 30 seconds, and dried at 60 ° C. for 10 minutes. Thus, a hole injection layer 104 with a thickness of 40 nm was produced.

  On the hole injection layer, the following blue light emitting layer composition, green light emitting layer composition and red light emitting layer composition were similarly discharged and injected using an inkjet head, irradiated with ultraviolet light for 30 seconds, 60 Drying treatment was performed at a temperature of 10 ° C. for 10 minutes to form respective light emitting layers (105B, 105G, 105R). Finally, Al (106) was vacuum-deposited as a cathode so as to cover the light emitting layer 105, and an organic EL element was produced.

  It was found that the produced organic EL element showed blue, green, and red light emission by applying a voltage to each electrode, and could be used as a full-color display device.

(Hole injection layer composition)
Compound A ₀ 20 parts by mass Cyclohexylbenzene 50 parts by mass Isopropyl biphenyl 50 parts by mass (Blue light emitting layer composition)
Compound 1 0.7 parts by mass Ir-15 0.04 parts by mass Cyclohexylbenzene 50 parts by mass Isopropyl biphenyl 50 parts by mass (green light emitting layer composition)
Compound 9 0.7 parts by mass Ir-1 0.04 parts by mass Cyclohexylbenzene 50 parts by mass Isopropyl biphenyl 50 parts by mass (red light emitting layer composition)
Compound 9 0.7 parts by mass Ir-14 0.04 parts by mass Cyclohexylbenzene 50 parts by mass Isopropyl biphenyl 50 parts by mass In addition, an organic EL device prepared by using compound 18 or compound 26 instead of compound 1 is similarly full-color. It was found that it can be used as a display device.

Example 3
<< Production of White Organic EL Element 3-1 >>
A transparent substrate provided with this ITO transparent electrode after patterning was performed on a substrate (NH-Technoglass NA-45) obtained by forming a 100 nm film of ITO (indium tin oxide) on a 100 mm × 100 mm × 1.1 mm glass substrate as an anode. The supporting substrate was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and UV ozone cleaning was performed for 5 minutes.

  On this transparent support substrate, a solution obtained by diluting poly (3,4-ethylenedioxythiophene) -polystyrene sulfonate (PEDOT / PSS, Bayer, Baytron P Al 4083) to 70% with pure water at 3000 rpm for 30 seconds. After forming into a film by the spin coat method, it dried at 200 degreeC for 1 hour, and provided the 1st positive hole transport layer with a film thickness of 30 nm.

Transferring the substrate to a nitrogen atmosphere, the first hole transporting layer, was formed 1000rpm a solution of Compound A ₀ of 50mg of toluene 10 ml, 30 seconds under the conditions of, by spin coating. After irradiating with ultraviolet light for 180 seconds to carry out photopolymerization / crosslinking, vacuum drying was performed at 60 ° C. for 1 hour to form a second hole transport layer.

  Next, using a solution obtained by dissolving Compound 10 (60 mg), Ir-12 (3.0 mg), and Ir-14 (3.0 mg) in 6 ml of toluene, a film is formed by spin coating under conditions of 1000 rpm and 30 seconds. did. Irradiated with ultraviolet light for 15 seconds to cause photopolymerization / crosslinking, and further heated in vacuum at 150 ° C. for 1 hour to obtain a light emitting layer.

  Furthermore, using a solution obtained by dissolving BCP (20 mg) in 6 ml of toluene, a film was formed by spin coating under conditions of 1000 rpm and 30 seconds. It was irradiated with ultraviolet light for 15 seconds to cause photopolymerization / crosslinking, and further heated in vacuum at 80 ° C. for 1 hour to form a hole blocking layer.

Subsequently, the substrate was fixed to a substrate holder of a vacuum deposition apparatus, the Alq ₃ was placed 200mg to molybdenum resistance heating boat was attached to a vacuum deposition apparatus. After reducing the vacuum chamber to 4 × 10 ⁻⁴ Pa, the heating boat containing Alq ₃ was heated by heating, and deposited on the electron transport layer at a deposition rate of 0.1 nm / second to further form a film. An electron transport layer having a thickness of 40 nm was provided.

  In addition, the substrate temperature at the time of vapor deposition was room temperature. Then, 0.5 nm of lithium fluoride and 110 nm of aluminum were vapor-deposited, the cathode was formed, and the organic EL element 3-1 was produced.

  When this element was energized, almost white light was obtained, indicating that it could be used as a lighting device. In addition, even if it replaced with the other compound of illustration, it turned out that white light emission is obtained similarly.

The schematic block diagram of an organic electroluminescent full color display apparatus is shown.

Explanation of symbols

101 Glass substrate 102 ITO transparent electrode 103 Partition 104 Hole injection layer 105B, 105G, 105R Light emitting layer

Claims (15)

A compound having a saturated hydrocarbon ring or an unsaturated hydrocarbon ring as a reactive group in an organic electroluminescence device having at least an anode and a cathode on a support substrate and having at least one light emitting layer between the anode and the cathode An organic electroluminescence device comprising (compound A) as a part and containing a polymer (polymer A) obtained by polymerizing the compound A via a reactive group. 2. The organic electroluminescence device according to claim 1, wherein the reactive group of the compound A is a cyclopropyl group or a cyclobutyl group. The said compound A is represented by the following general formula (a), The organic electroluminescent element of Claim 1 or 2 characterized by the above-mentioned.

(In the formula, Ar _{1 to} Ar ₉ represent a hydrogen atom or an aromatic ring, and at least one of the aromatic rings is an aromatic ring substituted with a cyclopropyl group or a cyclobutyl group.) 4. The organic electroluminescence device according to claim 3, wherein there are at least two aromatic rings substituted with the cyclopropyl group or cyclobutyl group. 5. The organic electroluminescence device according to claim 1, wherein the light emitting layer contains the compound A as at least a part and the polymer A. 6. The said light emitting layer contains the said compound A as at least one part, contains the said polymer A, and also contains the phosphorescence-emitting dopant, The any one of Claims 1-5 characterized by the above-mentioned. The organic electroluminescent element of description. The said polymer A is a copolymer of the said compound A and a phosphorescence-emitting dopant, The organic electroluminescent element of any one of Claims 1-5 characterized by the above-mentioned. The organic electroluminescence device according to claim 6 or 7, wherein the phosphorescent dopant is an Ir complex. The organic electroluminescence device according to claim 1, wherein the layer containing the compound A as at least a part and containing the polymer A is formed by a wet method. The organic electroluminescence element according to claim 1, wherein the compound A is polymerized after being applied. It has a some organic compound layer as a structure layer, The organic electroluminescent element of any one of Claims 1-10 characterized by the above-mentioned. At least one anode buffer layer between the anode and the light emitting layer, or at least one cathode buffer layer between the cathode and the light emitting layer, wherein at least one of the light emitting layers is The organic electro according to any one of claims 1 to 11, which comprises the compound A as at least a part, the polymer A, and the light emitting layer formed by a wet method. Luminescence element. The organic electroluminescence element according to claim 1, which emits white light. A display device comprising the organic electroluminescence element according to claim 1. An illuminating device comprising the organic electroluminescent element according to claim 1.

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