JP4962577B2 - Organic electroluminescence device - Google Patents

Description

  The present invention relates to an organic electroluminescence (hereinafter also abbreviated as organic EL) element, and specifically, suitable for consumer and industrial display devices such as a light-emitting multi-color or full-color display and a display panel. The present invention relates to an organic electroluminescence element to be used.

  As a light-emitting electronic display device, there is an electroluminescence display (ELD). As a component of ELD, an inorganic electroluminescent element and an organic electroluminescent element are mentioned. Inorganic electroluminescent elements have been used as planar light sources, but an alternating high voltage is required to drive the light emitting elements. An organic electroluminescence element has a structure in which a light emitting layer containing a compound that emits light is sandwiched between a cathode and an anode, and injects electrons and holes into the light emitting layer to recombine excitons. It is an element that emits light by utilizing light emission (fluorescence / phosphorescence) generated when this 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 complete solid-state device, it is attracting attention from the viewpoints of space saving and portability.

  However, for organic EL elements for practical use in the future, development of organic EL elements that emit light efficiently and with high brightness and long life is desired. Moreover, development of a low-cost organic EL element is desired. Various organic EL elements have been reported so far.

  A monochrome display using an organic EL element is a green monochrome display, which is a panel having a simple matrix structure with 256 × 64 pixels mounted on an in-vehicle FM character multiplex receiver (H Nakada and T. Tomah: Ext. Abstr. 7th Int. Workshop Inorganic and Organic Electroluminescence p. 385 (1996)). In contrast to monochrome displays, so-called area color displays that express several colors for each specific area of the display, blue, green, yellow, orange, and other colors are also available (May 7, 1999, Denpa Shimbun) Others), purple-blue and blue-purple have not been developed so far.

  As a compound that emits blue-violet light, the 61st Japan Society of Applied Physics Lecture Proceedings (2000.9 Hokkaido Institute of Technology) has announced that polysilane light-emitting diodes are used for organic EL devices. The light emitting diode has a short light emission lifetime, and the luminance tends to decrease due to the influence of the light emitting diode.

  However, in general, the organic phosphor is deteriorated and decomposed depending on the type of a medium such as a solvent or a resin, so that the emission intensity is lowered. In addition, under the strong light of about 100,000 lux, most of them decompose in a few minutes to a few hours, and there is no organic phosphor that can withstand long-term storage.

  Various reports have been made on compounds contained in the light emitting layer. The compounds contained in the light emitting layer are roughly classified into low molecular weight systems and high molecular weight systems.

  For low molecular weight systems, for example, Japanese Patent Application Laid-Open No. 3-152897 has reported an organic electroluminescence device containing p-quarterphenyl, but its emission luminance is low and not sufficient.

  Further, Patent Document 1 and Patent Document 2 examine compounds in which benzimidazole is incorporated into the molecule, but the light emission luminance is not sufficient.

  Patent Document 3 discloses a fluorescent material made of a pyrazoline compound, but it is insufficient from the viewpoint of thermal stability for use as a material for an organic EL device.

  The low molecular weight light-emitting material as described above has poor thermal stability when the molecular weight is small, and thus is easily decomposed and does not have a sufficient light emission lifetime.

  On the other hand, examples of the polymer material include a polysilane compound disclosed in JP-A-11-26159 and a polycarbonate disclosed in JP-A-5-247459. Since these are generally unstable, the light emission lifetime is short, it is difficult to continue light emission at room temperature, and the light emission efficiency is low.

  Further, a technique (doping) is known in which a very small amount (10 mol% or less) of a fluorescent material is mixed in a light emitting layer of an organic EL element, and light emitted from the light emitting layer is converted into light emitted from the fluorescent material. Advantages of the doping technique of introducing this small amount of fluorescent material include improvement in luminous efficiency and multicolor development. Specific doping techniques include the following.

  In Japanese Patent No. 3093796, a small amount of a fluorescent dopant is doped into a stilbene derivative, a distyrylarylene derivative or a tristyrylarylene derivative to achieve improvement in luminous efficiency and a longer lifetime of the device.

  Further, an element having an organic light-emitting layer doped with a trace amount of a fluorescent dopant (8) as a host compound using an 8-hydroxyquinoline aluminum complex as a host compound, and an 8-hydroxyquinoline aluminum complex as a host compound. A device having an organic light emitting layer doped with a quinacridone dye (Japanese Patent Laid-Open No. 3-255190) is known.

  However, in such conventional doping, it is known that the host compound absorbs blue, green, yellow, and orange light emission and emits longer-wave fluorescence. A host compound that absorbs blue fluorescence and emits light longer than that has not been known.

  Various reports have been made on the color conversion layer of the organic EL element. As color conversion materials used for the color conversion layer, those using organic phosphors have been reported in JP-A Nos. 3-12597, 9-245511, and 5-258860.

  Further, when the above organic phosphor is used for the color conversion layer, there is a disadvantage that an aggregate is easily formed by the interaction between molecules, and the emission wavelength becomes broad. It is also known that when the amount of the organic phosphor added is increased in order to increase the luminance, the association becomes more intense and concentration quenching occurs. As a result, even when the organic phosphor itself has a high quantum yield, when it is used as an organic EL device, the brightness is greatly reduced and the ability of the compound cannot be fully achieved.

  On the other hand, inorganic compounds generally have a long life. Furthermore, since the inorganic compound has a sharp emission wavelength and does not form an aggregate, the quantum yield is higher than that of the organic phosphor, so that the color conversion efficiency is good. Since the amount of added inorganic compound can be reduced and the power consumption can be reduced by the amount of good color conversion efficiency, the inorganic compound is useful as a color conversion material used in the color conversion layer.

  However, an inorganic compound has an excitation wavelength on the short wavelength side, and a blue light emitting material has a maximum emission wavelength on the longer wavelength side than the excitation wavelength of this inorganic compound, so that the inorganic compound can emit light with high color conversion efficiency. There wasn't. The quantum yield means the ratio of emitted photons to photons absorbed by the substance.

JP 10-92578 A JP 10-106749 A Japanese Unexamined Patent Publication No. 6-18431

  As described above, organic EL elements that have a long lifetime, emit light with high brightness, consume less power, and are low in cost are demanded as organic electroluminescent elements.

  The present invention has been made in view of the above situation.

  The present invention relates to an organic electroluminescent device that emits blue-violet or violet-blue light, an organic electroluminescent device that emits light with high brightness, an organic electroluminescent device that has a long lifetime, an organic electroluminescent device that has low power consumption, and a low-cost organic device. The present invention provides at least one of an electroluminescence element, an organic electroluminescence element with good color conversion efficiency, and an organic electroluminescence element that can be easily manufactured.

(1) An organic electroluminescence device having a cathode, an anode, and a light emitting layer, wherein the light emitting layer contains an organic compound represented by the following general formula (XVII).

(In the formula, R _e1 , R _e2 and R _e3 each independently represents a hydrogen atom. X ₄ , X ₅ and X ₆ each represent —NR _f —, an oxygen atom or a sulfur atom, and L ₄ , L ₅ , L ₆ represents a phenylene group, a pyridylene group, or a naphthylene group that may have a methyl group as a substituent, R _f represents an alkyl group that may be substituted with a fluorine atom, k ₄ , k ₅ , k ₆ represents 4.)
Moreover, the following is a preferable aspect.
(2) The organic electroluminescence device according to 1, wherein the organic compound has a band gap in the range of 2.96 to 3.80 eV.
(3) The organic electroluminescent device according to 1, wherein the organic compound has a band gap in the range of 3.20 eV to 3.60 eV.
(4) The organic electroluminescence device according to any one of 1 to 3, wherein the organic compound has a molecular weight of 600 to 2,000.
(5) The organic electroluminescence device according to any one of 1 to 4, which has an electron transport layer that transports electrons from the cathode, and the electron transport layer contains at least one kind of the organic compound. .
(6) The organic electroluminescence device according to any one of 1 to 5, further comprising at least one cathode buffer layer between the cathode and the light emitting layer.
(7) The organic electroluminescent element according to any one of 1 to 6, wherein the cathode has an aluminum content of 90% by mass or more and less than 100% by mass.
(8) The organic electroluminescence device according to any one of 1 to 7, which has a color conversion layer containing at least one phosphor.
(9) The organic electroluminescence device according to 8, wherein the phosphor is an inorganic phosphor.
(10) As the color conversion layer, a conversion layer containing at least one inorganic phosphor having a maximum emission wavelength in a range of 400 to 500 nm by absorbing light having a maximum emission wavelength of the organic compound; A light-absorbing light having a maximum emission wavelength of the organic compound and a light-absorbing light having a maximum emission wavelength of the organic compound, the conversion layer containing at least one inorganic phosphor having a maximum emission wavelength in the range of 501 to 600 nm. The organic electroluminescence device according to 8 or 9, further comprising: a conversion layer containing at least one inorganic phosphor having a maximum emission wavelength within a range of 601 to 700 nm.
(11) The organic electroluminescent element according to 9 or 10, wherein the inorganic phosphor is represented by the following general formula (A).
Formula _{(A) M x Ge y O} z F n: Mn m 4+
(However, M is an alkaline earth metal and satisfies n = 2x + 4 (y + m) −2z. N may be 0.)
(12) The organic electroluminescence device according to 11, wherein in the general formula (A), M is magnesium.
(13) The organic electroluminescence device according to 9 or 10, wherein the inorganic phosphor is represented by the following general formula (B).
Formula _{(B) N u Eu y (} W 1-t Mo t O 4) w
(However, M is an alkaline earth metal, 2W = u + 3v is satisfied, and t is 0 or an integer of 1.)
(14) The organic electroluminescence device according to 13, wherein in the general formula (B), N is potassium and t is 0.
(15) The organic electroluminescent element according to 9 or 10, wherein the inorganic phosphor is a rare earth complex phosphor.
(16) The organic electroluminescent element according to any one of 9 to 15, wherein the inorganic phosphor is manufactured by a Sol-Gel method.

  With the organic EL device of the present invention, an organic EL device having high brightness, long life, and low power consumption could be obtained.

It is a figure which shows an organic electroluminescent element. It is a figure which shows a CIE chromaticity coordinate.

  The present invention is as described above, and the following modes are also preferable as in the present invention. Hereinafter, the present invention and preferred embodiments thereof will be described.

(10 ′) An organic electroluminescence device having a cathode, an anode, and a light emitting layer,
The organic electroluminescent element containing the organic compound represented by the following general formula (XVI) in the said light emitting layer.

(Wherein R _c1 , R _c2 and R _c3 each independently represents a hydrogen atom or a substituent. X ₁ , X ₂ and X ₃ each represent —NR _d —, an oxygen atom or a sulfur atom. L ₁ , L ₂ and L ₃ each represent a linking group having a π bond, R _d represents an alkyl group, an aryl group, a substituted alkyl group or a substituted aryl group, and k ₁ , k ₂ and k ₃ each represents an integer of 0 to 6. To express.)
(12 ′) An organic electroluminescence device having a cathode, an anode, and a light emitting layer,
The organic electroluminescent element containing the organic compound represented by the following general formula (XVIII) in the said light emitting layer.

(In the formula, R _g1 , R _g2 and R _g3 each independently represent a hydrogen atom or a substituent. X ₇ , X ₈ and X ₉ each represent —NR _h —, an oxygen atom or a sulfur atom. L ₇ , L ₈ , and L ₉ each represent a linking group having a π bond, R _h represents an alkyl group, an aryl group, a substituted alkyl group, or a substituted aryl group, and k ₇ , k ₈ , and k ₉ each represents an integer of 0 to 6. To express.)
(13 ′) An organic electroluminescence device having a cathode, an anode, and a light emitting layer,
The organic electroluminescent element containing the organic compound represented by the following general formula (XIX) in the said light emitting layer.

(In the formula, R _i1 , R _i2 , R _i3 , R _j1 , R _j2 , and R _j3 each independently represent a hydrogen atom or a substituent. X ₁₀ , X ₁₁ , and X ₁₂ are —NR _k —, an oxygen atom, Or represents a sulfur atom, R _k represents an alkyl group, an aryl group, a substituted alkyl group, or a substituted aryl group, and k ₁₀ , k ₁₁ , and k ₁₂ represent an integer of 0 to 6.)
(14 ′) An organic electroluminescence device having a cathode, an anode, and a light emitting layer,
The organic electroluminescent element which contains at least 1 sort (s) of the organic compound represented by the following general formula (XX-1), (XX-2), (XX-3) or (XX-4) in the said light emitting layer.

_{(Wherein, R k1, R k2, R} k3, R k4, R k5, R k6, R k7, R k8, R l1, R l2, R l3, R l4, R l5, R l6, R l7, R _{l8, R m1, R m2,} R m3, R m4, R m5, R m6, R m7, R m8, R n1, R n2, R n3, R n4, R n5, R n6, R n7, R n8 is Each independently represents a hydrogen atom or a substituent.)
(30) An organic compound represented by the following general formula (XVI).

(Wherein R _c1 , R _c2 and R _c3 each independently represents a hydrogen atom or a substituent. X ₁ , X ₂ and X ₃ each represent —NR _d —, an oxygen atom or a sulfur atom. L ₁ , L ₂ and L ₃ each represent a linking group having a π bond, R _d represents an alkyl group, an aryl group, a substituted alkyl group or a substituted aryl group, and k ₁ , k ₂ and k ₃ each represents an integer of 0 to 6. To express.)
(31) An organic compound represented by the following general formula (XVII).

(Wherein R _e1 , R _e2 and R _e3 each independently represents a hydrogen atom or a substituent. X ₄ , X ₅ and X ₆ each represent —NR _f —, an oxygen atom or a sulfur atom. L _{4, L} 5, _{L 6}
Represents a linking group having a π bond. R _f represents an alkyl group, an aryl group, a substituted alkyl group, or a substituted aryl group. k ₄ , k ₅ , and k ₆ represent integers from 0 to 6. )
(32) An organic compound represented by the following general formula (XVIII).

(In the formula, R _g1 , R _g2 and R _g3 each independently represent a hydrogen atom or a substituent. X ₇ , X ₈ and X ₉ each represent —NR _h —, an oxygen atom or a sulfur atom. L ₇ , L ₈ , and L ₉ each represent a linking group having a π bond, R _h represents an alkyl group, an aryl group, a substituted alkyl group, or a substituted aryl group, and k ₇ , k ₈ , and k ₉ each represents an integer of 0 to 6. To express.)
(33) An organic compound represented by the following general formula (XIX).

(In the formula, R _i1 , R _i2 , R _i3 , R _j1 , R _j2 , and R _j3 each independently represent a hydrogen atom or a substituent. X ₁₀ , X ₁₁ , and X ₁₂ are —NR _k —, an oxygen atom, Or represents a sulfur atom, R _k represents an alkyl group, an aryl group, a substituted alkyl group, or a substituted aryl group, and k ₁₀ , k ₁₁ , and k ₁₂ represent an integer of 0 to 6.)
(34) Organic compound represented by the following general formula (XX-1), (XX-2), (XX-3) or (XX-4)

_{(Wherein, R k1, R k2, R} k3, R k4, R k5, R k6, R k7, R k8, R l1, R l2, R l3, R l4, R l5, R l6, R l7, R _{l8, R m1, R m2,} R m3, R m4, R m5, R m6, R m7, R m8, R n1, R n2, R n3, R n4, R n5, R n6, R n7, R n8 is Each independently represents a hydrogen atom or a substituent.)
(38) An inorganic phosphor represented by the following general formula (A).

Formula _{(A) M x Ge y O} z F n: Mn m 4+
(However, M is an alkaline earth metal and satisfies n = 2x + 4 (y + m) −2z. N may be 0.)
(39) A color conversion filter comprising at least one compound represented by the following general formula (A).

Formula _{(A) M x Ge y O} z F n: Mn m 4+
(However, M is an alkaline earth metal and satisfies n = 2x + 4 (y + m) −2z. N may be 0.)
(42) An organic electroluminescence device having a cathode, an anode, and a light emitting layer, containing an organic compound having a band gap of 2.96 eV to 3.80 eV, a phosphor, and in a range of 450 to 700 nm An organic electroluminescence device having at least one maximum emission wavelength therein.

  The organic electroluminescent element described in (1) can provide an organic electroluminescent element that emits blue-violet or violet-blue light, emits light with a long lifetime and high luminance, and has low power consumption.

  The organic electroluminescent device according to (10 ′), (12 ′), (13 ′), and (14 ′) provides an organic electroluminescent device that emits light with a long life, high luminance, and low power consumption. be able to.

  The organic compound described in (30), (31), (32), (33), or (34) can provide an organic compound that emits light in violet-blue or blue-violet with high luminance.

  With the inorganic phosphor described in (38), an inorganic phosphor having an excitation wavelength of 350 to 450 nm and emitting red light and having a long lifetime can be provided.

  The color conversion filter according to (39) can provide a color conversion filter that has an excitation wavelength of 350 to 450 nm and emits red light and has a long lifetime.

  According to the organic electroluminescent device described in (42), an organic electroluminescent device that has a long lifetime, emits light with high brightness, and has low power consumption can be provided.

  The present invention is described in detail below.

  The structure of the organic EL element will be described with reference to FIG. The organic EL element is composed of a light emitting layer 1 and an electrode composed of an anode 2 and a cathode 3. The light emitting layer 1 has a structure sandwiched between the anode 2 and the cathode 3. By passing an electric current through the electrodes, the organic compound contained in the light emitting layer 1 emits light. This is because positive and negative carriers are injected from the cathode 3 and the anode 2, and the carriers move and recombine in the organic layer, whereby a singlet excited state of the compound is formed, and the singlet excited state is changed to the ground state. It is believed that the compound emits light during the deactivation process. The organic EL element further includes a color conversion layer 4, and the color conversion layer 4 can convert light of a compound contained in the light emitting layer into light having a different wavelength. As shown in FIG. 1, full color can be realized by providing three color conversion layers having different wavelength regions. Reference numeral 5 denotes a substrate, and a glass substrate is usually used.

  The light emitting layer will be described.

  In the broad sense, the light emitting layer referred to in this specification refers to a layer that emits light when a current is passed through an electrode composed of a cathode and an anode. Specifically, it refers to a layer containing an organic compound that emits light when an electric current is passed. Usually, the light emitting layer has a structure in which the light emitting layer is held between a pair of electrodes. The organic EL device of the present invention has a hole injection layer, an electron injection layer, a hole transport layer and an electron transport layer in addition to the light emitting layer as required, and has a structure sandwiched between a cathode and an anode.

In particular,
(I) Anode / light emitting layer / cathode (ii) Anode / hole injection layer / light emitting layer / cathode (iii) Anode / light emitting layer / electron injection layer / cathode (iv) Anode / hole injection layer / light emitting layer / electron There are structures such as injection layer / cathode (v) anode / hole injection layer / hole transport layer / light emitting layer / electron transport layer / electron injection layer / cathode.

  Furthermore, a cathode buffer layer (for example, lithium fluoride) may be inserted between the electron injection layer and the cathode. Further, an anode buffer layer (for example, copper phthalocyanine) may be inserted between the anode and the hole injection layer.

  The light emitting layer may be provided with a hole injection layer, an electron injection layer, a hole transport layer, an electron transport layer, and the like on the light emitting layer itself. That is, (1) an injection function capable of injecting holes from an anode or a hole injection layer and applying electrons from a cathode or an electron injection layer when an electric field is applied, and (2) injection It may have at least one of the functions of transporting electric charges (electrons and holes) by the force of an electric field. In this case, a hole injection layer and an electron injection layer are provided separately from the light emitting layer. In addition, it is not necessary to provide at least one of the hole transport layer and the electron transport layer, so that the manufacturing cost can be reduced and the manufacturing process can be simplified. In addition, a function as a light emitting layer may be imparted by adding an organic compound that emits light to the hole injection layer, the electron injection layer, the hole transport layer, the electron transport layer, and the like.

  In particular, if the electron transport layer contains the organic compound used in the organic EL device of the present invention, the function of transporting electrons is also improved, so that the light emitting layer emits light with higher brightness and more power consumption. It becomes possible to hold down.

  As a method for forming a light emitting layer using the above-mentioned material, it can be formed by thinning by a known method such as vapor deposition, spin coating, casting, LB, etc. Preferably there is. Here, the molecular deposition film refers to a thin film formed by deposition from the gas phase state of the compound or a film formed by solidification from the molten state or liquid phase state of the compound. Usually, this molecular deposited film can be distinguished from a thin film (molecular accumulated film) formed by the LB method, a difference in aggregation structure and higher order structure, and a functional difference resulting therefrom.

  Further, as described in JP-A-57-51781, this light-emitting layer is obtained by dissolving the light-emitting material in a solvent together with a binder such as a resin and then forming a thin film by spin coating or the like. Can be formed. There is no restriction | limiting in particular about the film thickness of the light emitting layer formed in this way, Although it can select suitably according to a condition, Usually, it is the range of 5 nm-5 micrometers.

  As used herein, the band gap is the difference between the ionization potential and electron affinity of a compound. The ionization potential and electron affinity are determined based on the vacuum level. 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 the electron affinity is the LUMO (lowest empty molecule) of the electron at the vacuum level. Defined by the energy that falls to the orbital level and stabilizes.

  In the present invention, the band gap of the organic compound is obtained by measuring the absorption spectrum of the deposited film when the organic compound is deposited on glass to a thickness of 100 nm and converting the wavelength Ynm of the absorption edge into XeV. At this time, the following conversion formula was used.

Y = 10 ⁷ /(8066.541×X)
The ionization potential of the organic compound can be directly measured by photoelectron spectroscopy or can be obtained by correcting the electrochemically measured oxidation potential with respect to the reference electrode. In the case of the latter method, for example, when a saturated sweet potato electrode (SCE) is used as a reference electrode, it is expressed by ionization potential = oxidation potential (vs. SCE) +4.3 eV (“Molecular Semiconductors”, Springer- Verlag, 1985, page 98).

  In the present invention, the ionization potential Ip of the organic compound was directly measured by photoelectron spectroscopy. Specifically, the values were measured with a low energy electron spectrometer “Model AC-1” manufactured by Riken Keiki Co., Ltd.

  The electron affinity was determined according to the definition formula of band gap (band gap) = (ionization potential) − (electron affinity).

  In the present specification, “emits light emission in CIE chromaticity coordinates Purple Blue or Blue Purple” means that the light emitted from the light emitting layer of the organic EL element is emitted from a spectral radiance meter CS-1000 (Minolta). The measurement result was applied to the CIE chromaticity coordinates shown in FIG. 2 (“New Color Color Science Handbook”, page 108, FIG. 4.16 (edited by the Japan Color Society, University of Tokyo Press, 1985)). Sometimes, it is in the area of Purplish Blue (purple blue) and Bluish Purple (blue purple).

  Since at least one of the organic EL elements contains an organic compound having a band gap of 2.96 eV to 3.80 eV and emits light of purple-blue and blue-violet, the phosphor, particularly an inorganic phosphor. Can be emitted efficiently with color conversion.

  The organic compound used in the organic EL element preferably emits light in CIE chromaticity coordinate Blue Purple (blue violet), and thereby the inorganic phosphor can emit light with higher color conversion efficiency.

  Further, when the organic compound is an organic inorganic compound having a hetero atom, light is emitted with higher brightness. Thereby, an organic EL element with higher luminance can be provided.

  Furthermore, when the organic compound is an intermetallic compound having at least one heterocycle, light can be emitted with even higher luminance, thereby providing an organic EL device with higher luminance.

  At least one of the organic EL elements is particularly preferably an organic compound having a band gap of 3.20 eV to 3.60 eV in terms of color conversion efficiency.

  At least one of the organic EL elements preferably has an electron transport layer, and the electron transport layer preferably contains an organic compound contained in the light emitting layer of the organic EL element. Thus, the electron transport function is improved, so that it is possible to provide an organic electroluminescence element that emits light with higher brightness and lower power consumption.

  The organic EL element preferably has at least one buffer layer between the light-emitting layer and the cathode, whereby the life of the organic EL element can be significantly extended.

  As the organic compound that emits light contained in the light emitting layer of the organic EL element, it is preferable to contain a compound represented by the following general formula (I) that emits light with higher luminance.

  In the general formula (I), the central carbon-carbon bond can be written, for example, as follows, depending on how to write the resonance structural formula. sell.

In the general formula (I), Z ₁ and Z ₂ are necessary for forming a 5- or 6-membered hydrocarbon ring or a heterocyclic ring together with a carbon-carbon single bond or a carbon-carbon double bond. Represents a non-metallic atomic group. For example, as specific examples of a 5- or 6-membered hydrocarbon ring formed with Z ₁ , Z ₂ and a carbon-carbon single bond, or a carbon-carbon double bond, or a heterocyclic ring, furan, Thiophene, pyrrole, imidazole, pyrazole, 1,2,4-triazole, 1,2,3-triazole, oxazole, thiazole, isoxazole, isothiazole, furazane, pyridine, 4-hydroxypyridine (or tautomers thereof) ) 2-hydroxypyridine (or its tautomer), pyrazine, pyrimidine, pyridazine, indolizine, quinoline, isoindole, indole, isoquinoline, phthalazine, purine, naphthyridine, quinoxaline, quinazoline, cinnoline, pteridine, carbazole, Phenanthridine, acridine, perimidi Phenanthroline, phenazine, benzene, naphthalene, phenanthrene, anthracene, pyrene, cyclopentane, cyclohexane, cyclopentene, cyclopentadiene, cyclohexene, cyclohexadiene, and the like. In addition, they may each independently have a plurality of arbitrary substituents, and the plurality of substituents may be condensed with each other to further form a ring. Specific examples are as follows, but are not limited thereto. * Is a position which can be a carbon-carbon bond in the general formula (I).

  R represents a substituent. Examples of the substituent represented by R include an alkyl group (for example, a methyl group, an ethyl group, an isopropyl group, a hydroxyethyl group, a methoxymethyl group, a trifluoromethyl group, a perfluoropropyl group, a perfluoropropyl group, Fluoro-n-butyl group, perfluoro-t-butyl group, t-butyl group, etc.), cycloalkyl group (eg cyclopentyl group, cyclohexyl group etc.), aralkyl group (eg benzyl group, 2-phenethyl group etc.), aryl Groups (eg, phenyl, naphthyl, p-tolyl, p-chlorophenyl, etc.), alkoxy groups (eg, methoxy, ethoxy, isopropoxy, butoxy, etc.), aryloxy groups (eg, phenoxy), etc. Is mentioned. These groups may be further substituted. Examples of the substituent include a halogen atom, a hydrogen atom, a trifluoromethyl group, a cyano group, a nitro group, an alkyl group, an aryl group, an alkoxy group, an aryloxy group, and an alkylthio group. , Dialkylamino group, dibenzylamino group, diarylamino group and the like.

  The compound represented by the general formula (I) is preferably a compound represented by the following general formula (II) or (III) that emits light with particularly high luminance.

In the general formulas (II) and (III), Z ₃ , Z ₄ , Z ₅ and Z _{6 each} represents an optionally substituted aromatic hydrocarbon ring or heterocyclic ring, such as benzene, naphthalene, anthracene. , Azulene, phenanthrene, triphenylene, pyrene, chrysene, naphthacene, perylene, pentacene, hexacene, coronene, trinaphthylene, furan, thiophene, pyrrole, imidazole, pyrazole, 1,2,4-triazole, 1,2,3-triazole, oxazole , Thiazole, isoxazole, isothiazole, furazane, pyridine, 4-hydroxypyridine (or a tautomer thereof), 2-hydroxypyridine (or a tautomer thereof), pyrazine, pyrimidine, pyridazine, indolizine, Quinoline, isoindole, indian Represents isoquinoline, phthalazine, purine, naphthyridine, quinoxaline, quinazoline, cinnoline, pteridine, carbazole, phenanthridine, acridine, perimidine, phenanthroline, phenazine and the like. In addition, they may each independently have a plurality of arbitrary substituents, and the plurality of substituents may be condensed with each other to further form a ring.

R _{3 to} R ₆ represent a substituent, and examples of the substituent represented by R _{3 to} R ₆ include an alkyl group (for example, a methyl group, an ethyl group, an isopropyl group, a hydroxyethyl group, a methoxymethyl group, a trifluoromethyl group). Group, perfluoropropyl group, perfluoro-n-butyl group, perfluoro-t-butyl group, t-butyl group etc.), cycloalkyl group (eg cyclopentyl group, cyclohexyl group etc.), aralkyl group (eg benzyl group, 2-phenethyl group etc.), aryl group (eg phenyl group, naphthyl group, p-tolyl group, p-chlorophenyl group etc.), alkoxy group (eg methoxy group, ethoxy group, isopropoxy group, butoxy group etc.), aryloxy Group (for example, phenoxy group and the like) and the like. These groups may be further substituted. Examples of the substituent include a halogen atom, a hydrogen atom, a trifluoromethyl group, a cyano group, a nitro group, an alkyl group, an aryl group, an alkoxy group, an aryloxy group, and an alkylthio group. , Dialkylamino group, dibenzylamino group, diarylamino group and the like.

  The compounds represented by the general formulas (II) and (III) have the following general formulas (IV), (V), (VI), (VII), (VIII), (IX), (IX) that emit light with particularly high luminance. X), (XI), and a compound represented by (XII) are preferable.

R _{a1 to} R _a19 each independently represent a hydrogen atom or a substituent, and the substituent represented by R _{a1 to} R _{a19 has the same meaning} as the substituent represented by R _{3 to} R ₆ . Things.

  As the light emitting compound contained in the light emitting layer of the organic EL device, general formulas (IV), (V), (VI), (VII), (VIII), (IX), (X) that emit light with high luminance are used. , (XI), (XII) are preferably compounds in which the residues obtained by removing a hydrogen atom or a substituent from a compound selected from at least two compounds selected from the compounds represented by (XI) and (XII) are bonded to each other by a non-conjugated linking group. .

  Examples of the non-conjugated linking group include divalent, trivalent and tetravalent ones. Specific examples include a substituted or unsubstituted saturated alkylene group, an aromatic hydrocarbon ring, a heterocyclic ring, and the like. The substituted or unsubstituted saturated alkylene group may contain a hetero atom and may partially form a ring.

  Specific non-conjugated linking groups are shown below. * Represents the position where the residue is bound.

  A compound selected from at least two compounds represented by formulas (IV), (V), (VI), (VII), (VIII), (IX), (X), (XI), (XII) Specifically, as a compound in which each residue is bonded with a non-conjugated linking group, a compound represented by the following general formula (XIII), (XIV) or (XV) emits light with higher brightness. It is preferable to contain at least one of these in the light emitting layer.

Z _{7 to} Z _{14 each} represents a nonmetallic atom group necessary for forming an aromatic hydrocarbon ring or a heterocyclic ring, and specifically, the same as those represented by Z _{3 to} Z ₆ Is mentioned. Lx, Ly, and Lz each represent a divalent, trivalent, or tetravalent linking group. Specific examples include a substituted or unsubstituted saturated alkylene group, an aromatic hydrocarbon ring, a heterocyclic ring, and the like. The substituted or unsubstituted saturated alkylene group may contain a hetero atom and may partially form a ring.

  The band gaps of the organic compounds represented by the general formulas (I) to (XII) are preferably 3.20 eV to 3.60 eV, which can emit blue-violet or purple-blue with higher luminance. it can.

  In addition, since the organic compounds represented by the general formulas (I) to (XII) have a high glass transition temperature (Tg), they have sufficient thermal stability as a material for the organic electroluminescence element.

  The organic compounds represented by the general formulas (XVI), (XVII), (XVIII), (XIX), (XX-1), (XX-2), (XX-3), (XX-4) are purple It is a compound that emits blue or blue-violet light. In addition, since it is an organic compound that emits light with high brightness, it is useful as a compound that emits light to be contained in the light emitting layer of an organic electroluminescence device. It can also be used as a material such as a labeling compound for pharmaceuticals used.

  Further, organic compounds represented by the following general formulas (XVI), (XVII), (XVIII), (XIX), (XX-1), (XX-2), (XX-3), (XX-4) Since the glass transition temperature (Tg) is high, the thermal stability as a material of the organic electroluminescence element is also sufficient.

  The organic compounds represented by the general formulas (XVI), (XVII), (XVIII), (XIX), (XX-1), (XX-2), (XX-3), (XX-4) are converted into organic EL. When it is contained in the light emitting layer of the layer, the band gap is preferably in the range of 2.96 to 3.80 eV, more preferably 3.20 eV to 3.60 eV. Thereby, blue-violet or purple-blue can be emitted with higher luminance.

  It is represented by the organic compound represented by the general formula (XVI), (XVII), (XVIII), (XIX), (XX-1), (XX-2), (XX-3), (XX-4). The molecular weight of the compound is preferably in the range of 600-2000. When the molecular weight is within this range, the light emitting layer can be easily produced by a vacuum deposition method, and the production of the organic EL element is facilitated. Furthermore, the thermal stability of the organic compound in the organic EL element is improved.

  Specific examples of the compounds represented by the general formulas (I) to (XX) are shown below, but are not limited thereto.

  In the organic EL element, a region (doping region) containing a phosphor (dopant) is not specified, and it is only necessary to contain a dopant, but the phosphor is preferably contained in the light emitting layer. The thickness of the layer in the doping region is preferably 5 nm to 100 nm. If the doping region is too thin, the color conversion effect is small. The concentration of the fluorescent dopant used is preferably 0.001 to 10 mol%. If the concentration of the fluorescent dopant is too small, the effect of color conversion is thin. On the other hand, if the concentration is too large, concentration quenching occurs because the excited state is deactivated without emitting light due to molecular association.

  Arbitrary dopants are used for the organic EL element. A preferred dopant is a fluorescent organic molecule having a high fluorescence quantum yield in a solution state or a rare earth complex-based phosphor. Here, the fluorescence quantum yield is preferably 10% or more, particularly preferably 30% or more. Any solution may be used for the measurement of the fluorescence quantum yield as long as the compound is soluble, and acetonitrile, tetrahydrofuran, cyclohexane, benzene, dimethylformamide, dichloromethane, toluene and the like are considered.

  Examples of fluorescent organic molecules having a high fluorescence quantum yield include coumarin dyes, pyran dyes, cyanine dyes, croconium dyes, squalium dyes, oxobenzanthracene dyes, fluorescein dyes, rhodamine dyes, and pyrylium dyes. Examples include dyes, perylene dyes, stilbene dyes, and polythiophene dyes.

  Moreover, as the rare earth complex phosphor, a rare earth complex phosphor described in detail later can be used.

  Next, the hole injection layer and the electron injection layer will be described.

  The hole injection layer and the hole transport layer have a function of transmitting the holes injected from the anode to the light emitting layer, and the hole injection layer and the hole transport layer are interposed between the anode and the light emitting layer. Therefore, a lot of holes are injected into the light emitting layer with a lower electric field, and the electrons injected into the light emitting layer from the cathode, the electron injection layer, or the electron transport layer are converted into the light emitting layer and the hole injection layer or the hole transport layer. Due to the barrier of electrons existing at the interface, the device has excellent light emitting performance, such as being accumulated at the interface in the light emitting layer and improving the light emission efficiency. The material for the hole injection layer and the hole transport layer (hereinafter referred to as the hole injection material and the hole transport material) is not particularly limited as long as it has the above-mentioned preferable properties. Any of those commonly used as hole charge injection and transport materials and known materials used for hole injection layers and hole transport layers of EL devices can be selected and used.

  The hole injection material and the hole transport material have either hole injection or transport or electron barrier properties, and may be either organic or inorganic. Examples of the hole injection material and hole transport material include triazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives and pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, oxazoles. Derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, stilbene derivatives, silazane derivatives, aniline copolymers, and conductive polymer oligomers, particularly thiophene oligomers. As the hole injecting material and the hole transporting material, the above-mentioned materials can be used, and porphyrin compounds, aromatic tertiary amine compounds and styrylamine compounds, particularly aromatic tertiary amine compounds can be used. preferable.

  Representative examples of the aromatic tertiary amine compound and styrylamine compound 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; Bis (4-di-p-tolylaminophenyl) cyclohexane; N, N, N ′, N′-tetra-p-tolyl-4,4′-diaminobiphenyl; 1,1-bis (4-di-p- Tolylaminophenyl) -4-phenylcyclohexane; bis (4-dimethylamino-2-methylphenyl) phenylmethane; bis (4-di-p-tolylaminophenyl) phenylmethane; N, N′-diphenyl-N, N -Di (4-methoxyphenyl) -4,4'-diaminobiphenyl; N, N, N ', N'-tetraphenyl-4,4'-diaminodiphenyl ether; 4,4'-bis (diphenylamino) quadri N; N, N-tri (p-tolyl) amine; 4- (di-p-tolylamino) -4 ′-[4- (di-p-tolylamino) styryl] stilbene; 4-N, N-diphenyl Amino- (2-diphenylvinyl) benzene; 3-methoxy-4′-N, N-diphenylaminostilbenzene; N-phenylcarbazole and also two condensations described in US Pat. No. 5,061,569 Having an aromatic ring in the molecule, for example, 4,4′-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (NPD), JP-A-4-308 4,4 ′, 4 ″ -tris [N- (3-methylphenyl) -N-phenylamino] triphenylamine in which three triphenylamine units described in Japanese Patent No. 88 are linked in a starburst type (MTDATA).

  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. The hole injection layer and the hole transport layer are formed by thinning the hole injection material and the hole transport material by a known method such as a vacuum deposition method, a spin coating method, a casting method, or an LB method. Can be formed. Although there is no restriction | limiting in particular about the film thickness of a positive hole injection layer and a positive hole transport layer, Usually, it is about 5 nm-5 micrometers. The hole injection layer and hole transport layer may have a single layer structure composed of one or more of the above materials, or may have a multilayer structure composed of a plurality of layers having the same composition or different compositions. Furthermore, the electron transport layer used as necessary only needs to have a function of transmitting electrons injected from the cathode to the light emitting layer, and the material thereof is selected from any conventionally known compounds. Can be used.

  Examples of materials used for this electron transport layer (hereinafter referred to as electron transport materials) include heterocyclic tetracarboxylic acid anhydrides such as nitro-substituted fluorene derivatives, diphenylquinone derivatives, thiopyran dioxide derivatives, naphthalene perylene, carbodiimides, Examples include fluorenylidenemethane derivatives, anthraquinodimethane and anthrone derivatives, and oxadiazole derivatives. 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), etc., and the central metals of these metal complexes are In, Mg, Cu , Ca, Sn, Ga, or Pb can also be used as an 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 transport 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 similarly to the hole injection layer and the hole transport layer, inorganic such as n-type-Si and n-type-SiC. A semiconductor can also be used as an electron transport material.

  This electron transport layer can be formed by forming the above compound by a known thinning method such as a vacuum deposition method, a spin coating method, a casting method, or an LB method. Although the film thickness as an electron carrying layer does not have a restriction | limiting in particular, Usually, it selects in 5 nm-5 micrometers. The electron transport layer may have a single layer structure composed of one or two or more of these electron transport materials, or may have a laminated structure composed of a plurality of layers having the same composition or different compositions.

  The substrate preferably used in the organic EL device of the present invention is not particularly limited in the kind of glass, plastic, etc., and is not particularly limited as long as it is transparent. Examples of the substrate preferably used for the electroluminescence device of the present invention include glass, quartz, and a light transmissive plastic film.

  Examples of the light transmissive plastic film include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), polyetherimide, polyetheretherketone, polyphenylene sulfide, polyarylate, polyimide, and polycarbonate (PC). And a film made of cellulose triacetate (TAC), cellulose acetate propionate (CAP), or the like.

  Next, a suitable example for producing the organic EL element will be described. As an example, a method for producing an EL device comprising the above-mentioned anode / hole injection layer / hole transport layer / light emitting layer / electron transport layer / electron injection layer / cathode will be described. First, a desired electrode is formed on a suitable substrate. A thin film made of a material, for example, a material for an anode, is formed by a method such as vapor deposition or sputtering so as to have a film thickness of 1 μm or less, preferably in the range of 10 to 200 nm, to produce an anode. Next, a thin film comprising a hole injection layer, a hole transport layer, a light emitting layer, and an electron transport layer / electron injection layer, which is a device material, is formed thereon.

  Furthermore, a buffer layer (electrode interface layer) may be present between the anode and the light emitting layer or hole injection layer and between the cathode and the light emitting layer or electron injection layer.

  The buffer layer is a layer that is provided between the electrode and the organic layer in order to reduce drive voltage and improve luminous efficiency. “Organic EL element and its forefront of industrialization (November 30, 1998, issued by NTS Corporation) 2) Chapter 2 “Electrode Materials” (pages 123 to 166) in detail, and includes an anode buffer layer and a cathode buffer layer.

  The details of the anode buffer layer are described in JP-A-9-45479, JP-A-9-260062, JP-A-8-288069 and the like. Specific examples thereof include a phthalocyanine buffer layer represented by copper phthalocyanine, vanadium oxide. And an oxide buffer layer, 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 are described in JP-A-6-325871, JP-A-97574, JP-A-10-74586 and the like, specifically, a metal buffer layer represented by strontium, aluminum and the like, Examples thereof include an alkali metal compound buffer layer typified by lithium fluoride, an alkaline earth metal compound buffer layer typified by magnesium fluoride, and an oxide buffer layer typified by aluminum oxide.

  The buffer layer is preferably a very thin film, and depending on the material, the film thickness is preferably in the range of 0.1 to 100 nm.

  Further, in addition to the basic constituent layer, a layer having other functions may be laminated as required. For example, JP-A-11-204258, 11-204359, and “Organic EL device and its industrialization front ( It may have a functional layer such as a hole blocking layer described on page 237 of “November 30, 1998, issued by NTS Corporation”.

  The buffer layer may function as a light emitting layer when at least one of the compounds of the present invention is present in at least one of the cathode buffer layer and the anode buffer layer.

  Next, the electrode of the organic EL element will be described. The electrode of the organic EL element consists of a cathode and an 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.

  The anode may be formed by forming a thin film by depositing these electrode materials by a method such as vapor deposition or sputtering, and a pattern having a desired shape may be formed by a photolithography method, or (100 μm when pattern accuracy is not required so much). As described above, a pattern may be formed through a mask having a desired shape when the electrode material is deposited or sputtered. When light emission is extracted from the anode, it is desirable that the transmittance is 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 nm to 1 μm, preferably 10 nm to 200 nm.

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, a mixture of an electron injecting metal and a second metal which is a stable metal having a larger work function value than this from the viewpoint of durability against electron injecting and oxidation, for example, a magnesium / silver mixture, magnesium An aluminum / aluminum mixture, a magnesium / indium mixture, an aluminum / aluminum oxide (Al ₂ O ₃ ) mixture, a lithium / aluminum mixture, and the like are preferable.

  Furthermore, as the cathode used in the organic EL device of the present invention, an aluminum alloy is preferable, and the aluminum content is particularly preferably 90% by mass or more and less than 100% by mass, and most preferably 95% by mass or more and less than 100% by mass. . Thereby, the light emission lifetime and the highest reached luminance of the organic EL element can be further improved.

  The cathode can be produced by forming a thin film of these electrode materials by a method such as vapor deposition or sputtering. Further, 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 1 μm, preferably 50 to 200 nm. In order to transmit light, if either the anode or the cathode of the organic EL element is transparent or translucent, the light emission efficiency is improved, which is convenient.

As a method for thinning the organic thin film layer, there are a spin coating method, a casting method, a vapor deposition method and the like as described above. From the viewpoint that a homogeneous film is easily obtained and pinholes are not easily generated. Vapor deposition or spin coating is particularly preferred. Further, a different film forming method may be applied for each layer. When a vapor deposition method is employed for film formation, the vapor deposition conditions vary depending on the type of compound used, the target crystal structure of the molecular deposition film, the association structure, etc., but generally a boat heating temperature of 50 to 450 ° C. and a degree of vacuum of 10 It is desirable to select appropriately within the range of ⁻⁶ to 10 ⁻² Pa, a deposition rate of 0.01 to 50 nm / second, a substrate temperature of −50 to 300 ° C., and a film thickness of 5 nm to 5 μm.

  After forming these layers, 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 in the range of 50 to 200 nm, and a cathode is provided. Thus, a desired EL element can be obtained. The organic EL element is preferably produced from the hole injection layer to the cathode consistently by a single evacuation, but it may be taken out in the middle and subjected to a different film forming method. Therefore, it is necessary to consider that the work is performed in a dry inert gas atmosphere.

  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 EL element thus obtained, light emission can be observed by applying a voltage of about 5 to 40 V with the anode being + and the cathode being-. Further, even when a voltage is applied with the opposite polarity, no current flows and no light emission occurs. Further, when an AC voltage is applied, light is emitted only when the anode is in the + state and the cathode is in the-state. The alternating current waveform to be applied may be arbitrary.

  Next, the color conversion layer will be described.

  The color conversion layer referred to in this specification refers to a layer having a function of converting light having a certain wavelength into light having a different wavelength in a broad sense. Specifically, it refers to a layer containing substances that absorb light and emit light of different wavelengths.

  The organic EL device of the present invention preferably has a color conversion layer containing a phosphor. Thus, the organic EL element can display not only the color of light emitted from the light emitting layer but also other colors converted by the color conversion layer.

  The phosphor contained in the color conversion layer used in the present invention particularly preferably contains an inorganic phosphor. Thereby, since the light emitted from the light emitting layer of the organic EL element is converted with high color conversion efficiency, the power consumption of the organic EL element can be suppressed.

  As a color conversion layer used in the present invention, a color conversion layer containing an inorganic phosphor that emits light having a maximum emission wavelength in the range of 400 to 500 nm when excited by the emission wavelength of the organic compound in the emission layer, and emission A color conversion layer containing an inorganic phosphor that emits light with a maximum emission wavelength in the range of 501 to 600 nm when excited by the emission wavelength of the organic compound in the layer, and excited by the emission wavelength of the organic compound in the emission layer It is preferable to have at least a color conversion layer containing an inorganic phosphor that emits light having a maximum emission wavelength within a range of 601 to 700 nm. Thereby, the organic EL element can be made full color.

  Moreover, as long as full colorization is achieved efficiently, you may have four or more color conversion layers.

The composition of the inorganic phosphor is not particularly limited, but metal oxides such as Y ₂ O ₂ S, Zn ₂ SiO ₄ , Ca ₅ (PO ₄ ) ₃ Cl, etc., which are crystal bases, and ZnS, SrS, CaS. And sulfides such as Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and other rare earth metal ions, Ag, Al, Mn, In, Cu A combination of metal ions such as Sb as activator or coactivator is preferable.

The crystal matrix will be described in more detail. As the crystal matrix, a metal oxide is preferable. For example, (X) ₃ Al ₁₆ O ₂₇ , (X) ₄ Al ₁₄ O ₂₅ , (X) ₃ Al ₂ Si ₂ O ₁₀ , ( X) ₄ Si ₂ O ₈ , (X) ₂ Si ₂ O ₆ , (X) ₂ P ₂ O ₇ , (X) ₂ P ₂ O ₅ , (X) ₅ (PO ₄ ) ₃ Cl, (X) ₂ Si ₃ O ₈ -2 (X) Cl ₂ [wherein X represents an alkaline earth metal. The alkaline earth metal represented by X may be a single component or two or more mixed components, and the mixing ratio may be arbitrary. As typical crystal bases, aluminum oxide, silicon oxide, phosphoric acid, halophosphoric acid and the like substituted with an alkaline earth metal such as

  Other preferable crystal matrixes include oxides and sulfides of zinc, oxides of rare earth metals such as yttrium, gadolinium and lanthanum, and oxides in which part of the oxygen is replaced with sulfur atoms (sulfides), and Examples include rare earth metal sulfides and oxides or sulfides thereof containing any metal element.

  Preferred examples of the crystal matrix are listed below.

Mg ₄ GeO _5.5 F, Mg ₄ GeO ₆ , ZnS, Y ₂ O ₂ S, Y ₃ Al ₅ O ₁₂ , Y ₂ SiO ₁₀ , Zn ₂ SiO ₄ , Y ₂ O ₃ , BaMgAl ₁₀ O ₁₇ , BaAl ₁₂ O ₁₉ , (Ba, Sr, Mg) O.aAl ₂ O ₃ , (Y, Gd) BO ₃ , (Zn, Cd) S, SrGa ₂ S ₄ , SrS, GaS, SnO ₂ , Ca ₁₀ (PO ₄ ) ₆ (F, Cl) ₂ , (Ba, Sr) (Mg, Mn) Al ₁₀ O ₁₇ , (Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ , (La, Ce) PO ₄ , CeMgAl ₁₁ O ₁₉ , GdMgB ₅ O ₁₀ , Sr ₂ P ₂ O ₇ , Sr ₄ Al ₁₄ O ₂₅ , Y ₂ SO ₄ , Gd ₂ O ₂ S, Gd ₂ O ₃ , YVO ₄ , Y (P, V) O ₄ Etc.

  The above crystal matrix and activator or coactivator may be partially replaced with elements of the same family, and there is no particular restriction on the element composition, and visible light is absorbed by absorbing light in the ultraviolet region or light in the purple region. Anything can be used.

  In the present invention, preferred as the activator and coactivator of the inorganic phosphor are ions of lanthanoid elements represented by La, Eu, Tb, Ce, Yb, Pr and the like, Ag, Mn, Cu, In, Al, etc. The metal ion is preferably from 0.001 to 100 mol%, more preferably from 0.01 to 50 mol%, based on the matrix.

  The activator and coactivator are doped into the crystal by replacing some of the ions constituting the crystal matrix with ions such as the above lanthanoids.

Strictly speaking, the actual composition of the phosphor crystal has the following composition formula, but since the amount of the activator often does not affect the intrinsic fluorescence properties, the following is especially true: Unless stated, the following numerical values of x and y are not described. For example, Sr _4-x Al ₁₄ O ₂₅ : Eu ²⁺ _x is expressed as Sr ₄ Al ₁₄ O ₂₅ : Eu ²⁺ in the present invention.

The inorganic phosphor used in the color conversion layer of the organic EL device of the present invention preferably contains an inorganic phosphor represented by the following general formula (A).
Formula _{(A) M x Ge y O} z F n: Mn m 4+
(However, M is an alkaline earth metal, and n = 2x + 4 (y + m) −2Z is satisfied. N may be 0)
By using the inorganic phosphor represented by the general formula (A), the color conversion efficiency is improved with a longer lifetime, and therefore, an organic EL element with a longer lifetime and low power consumption can be provided.

  The inorganic phosphor represented by the general formula (A) preferably has a maximum emission wavelength in the range of 601 to 700 nm, and the phosphor represented by the general formula (A) is such that M is magnesium. preferable. Thereby, an organic EL element with high red purity can be provided.

The inorganic phosphor used for the color conversion layer preferably contains an inorganic phosphor represented by the following general formula (B).
Formula _{(B) N u E uy (} W 1-t MoO 4) w
(However, M is an alkaline earth metal, 2W = u + 3v is satisfied, and t is an integer of 0 or 1.)
By using the inorganic phosphor represented by the general formula (B), the color conversion efficiency is improved with a longer lifetime, so that an organic EL element with a longer lifetime and low power consumption can be provided.

  The inorganic phosphor represented by the general formula (B) preferably has a maximum emission wavelength in the range of 601 to 700 nm, and the phosphor represented by the general formula (B) is such that N is potassium. preferable. Thereby, an organic EL element with high red purity can be provided.

The composition formulas of typical inorganic phosphors (inorganic phosphors composed of a crystal matrix and an activator) are described below, but the present invention is not limited to these. _{(Ba z Mg 1-z)} 3-x-y Al 16 O 27: Eu 2+ x, Mn 2+ y, Sr 4-x Al 14 O 25: Eu 2+ x, (Sr 1-z Ba z) 1-x Al ₂ Si ₂ O ₈ : Eu ²⁺ _x , Ba _2−x SiO ₄ : Eu ²⁺ _x , Sr _2−x SiO ₄ : Eu ²⁺ _x , Mg _2−x SiO ₄ : Eu ²⁺ _x , (BaSr) _1-x SiO ₄ : Eu ²⁺ _x , Y _2−x−y SiO ₅ : Ce ³⁺ _x , Tb ³⁺ _y , Sr _2−x P ₂ O ₅ : Eu ²⁺ _x , Sr _2−x P ₂ O ₇ : Eu ²⁺ _x , _{(Ba y Ca z Mg 1-} y-z) 5-x (PO 4) 3 Cl: Eu 2 + x, Sr 2-x Si 3 O 8 -2SrCl 2: Eu 2+ x [x, y and z are each 1 or less Represents any number of. ]
The inorganic phosphors preferably used in the present invention are shown below, but the present invention is not limited to these compounds.
[Blue light emitting inorganic phosphor]
(BL-1) Sr ₂ P ₂ O ₇ : Sn ⁴⁺
(BL-2) Sr ₄ Al ₁₄ O ₂₅ : Eu ²⁺
(BL-3) BaMgAl ₁₀ O ₁₇ : Eu ²⁺
(BL-4) SrGa ₂ S ₄ : Ce ³⁺
(BL-5) CaGa ₂ S ₄ : Ce ³⁺
(BL-6) (Ba, Sr) (Mg, Mn) Al ₁₀ O ₁₇ : Eu ²⁺
(BL-7) (Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu ²⁺
(BL-8) BaAl ₂ SiO ₈ : Eu ²⁺
(BL-9) Sr ₂ P ₂ O ₇ : Eu ²⁺
_{(BL-10) Sr 5 (} PO 4) 3 Cl: Eu 2+
(BL-11) (Sr, Ca, Ba) ₅ (PO ₄ ) ₃ Cl: Eu ²⁺
_{(BL-12) BaMg 2 Al} 16 O 27: Eu 2+
(BL-13) (Ba, Ca) ₅ (PO ₄ ) ₃ Cl: Eu ²⁺
(BL-14) Ba ₃ MgSi ₂ O ₈ : Eu ²⁺
(BL-15) Sr ₃ MgSi ₂ O ₈ : Eu ²⁺
[Green light emitting inorganic phosphor]
(GL-1) (BaMg) Al ₁₆ O ₂₇ : Eu ²⁺ , Mn ²⁺
(GL-2) Sr ₄ Al ₁₄ O ₂₅ : Eu ²⁺
(GL-3) (SrBa) Al ₂ Si ₂ O ₈ : Eu ²⁺
(GL-4) (BaMg) ₂ SiO ₄ : Eu ^{2+
_{(GL-5) Y 2 SiO}} 5: Ce 3+, Tb 3+
_{(GL-6) Sr 2 P} 2 O 7 -Sr 2 B 2 O 5: Eu 2+
(GL-7) (BaCaMg) ₅ (PO ₄ ) ₃ Cl: Eu ²⁺
_{(GL-8) Sr 2 Si} 3 O 8 -2SrCl 2: Eu 2+
_{(GL-9) Zr 2 SiO} 4, MgAl 11 O 19: Ce 3+, Tb 3+
(GL-10) Ba ₂ SiO ₄ : Eu ²⁺
(GL-11) Sr ₂ SiO ₄ : Eu ²⁺
_{(GL-12) (BaSr)} SiO 4: Eu 2+
[Red light-emitting inorganic phosphor]
(RL-1) Y ₂ O ₂ S: Eu ³⁺
(RL-2) YAlO ₃ : Eu ³⁺
(RL-3) Ca ₂ Y ₂ (SiO ₄ ) ₆ : Eu ³⁺
(RL-4) LiY ₉ (SiO ₄ ) ₆ O ₂ : Eu ³⁺
(RL-5) YVO ₄ : Eu ³⁺
(RL-6) CaS: Eu ³⁺
(RL-7) Gd ₂ O ₃ : Eu ³⁺
(RL-8) Gd ₂ O ₂ S: Eu ³⁺
(RL-9) Y (P, V) O ₄ : Eu ³⁺
(RL-10) Mg ₄ GeO _5.5 F: Mn ⁴⁺
(RL-11) Mg ₄ GeO ₆ : Mn ⁴⁺
(RL-12) K ₅ Eu _2.5 (WO ₄ ) _6.25
(RL-13) Na ₅ Eu _2.5 (WO ₄ ) _6.25
(RL-14) K ₅ Eu _2.5 (MoO ₄ ) _6.25
(RL-15) Na ₅ Eu _2.5 (MoO ₄ ) _6.25
The inorganic phosphor may be subjected to a surface modification treatment as required, and as a method thereof, a chemical treatment such as a silane coupling agent or a physical treatment by adding submicron order fine particles or the like. And those obtained by using them in combination.

  As the silane coupling agent, those described in the “NUC silicone silane coupling agent” catalog issued by Nihon Unicar Co., Ltd. (August 2, 1997) can be used as they are. Specific examples thereof include, for example, β- (3,4-epoxycyclohexyl) -ethyltrialkoxysilane, glycidyloxyethyltriethoxysilane, γ-acryloyloxy-n-propyltri-n-propyloxysilane, γ-methacryloyloxy-n-propyl-n-propyloxy Silane, di (γ-acryloyloxy-n-propyl) di-n-propyloxysilane, acryloyloxydimethoxyethylsilane, N-β (aminoethyl) γ-aminopropyltrimethoxysilane, N-β (aminoethyl) γ- Aminopropylmethyldimethoxysilane γ- aminopropyltriethoxysilane, N- phenyl--γ- aminopropyltrimethoxysilane, etc. γ- mercaptopropyl trimethoxysilane.

  The fine particles are preferably inorganic fine particles, and examples thereof include fine particles such as silica, titania, zirconia, and zinc oxide.

  Inorganic phosphors are preferably those that do not undergo a mechanical crushing process at the time of production, that is, those that are synthesized by a build-up method, and those that are produced by a Sol-Gel method or the like are particularly preferable. Moreover, what has an inorganic oxide as a base | matrix is preferable on a composition. Color conversion efficiency can be further improved.

The manufacturing method based on the Sol-Gel method is described in detail in, for example, “Application of the Sol-Gel Method” by Sakuo Sakuo (published by Agne Jofusha, 1997). Means a method of synthesizing a material at a lower temperature than the melting method through sol-formation and gelation of the solution. The “Sol-Gel method” in the present invention is a liquid-phase method in at least one step of phosphor production. It can be distinguished from a synthesis method performed by a melt reaction applied to normal inorganic phosphor synthesis. In the Sol-Gel method of the present invention, generally, an element (metal) used for a base, an activator, or a coactivator is, for example, tetramethoxysilane (Si (OCH ₃ ) ₄ ) or europium-2,4-pentanedionate. Metal alkoxides and metal complexes such as (Eu ³⁺ (CH ₃ COCH═C (O—) CH ₃ ) ₃ ), or double alkoxides formed by adding a simple metal to an organic solvent solution thereof (for example, Al (OBu) ₃ 2 -Mg [Al (OBu) ₃ ] ₂ etc. made by adding magnesium metal to butanol solution), metal halide, metal salt of organic acid, necessary amount of metal as a simple substance, and mixed thermally or chemically in liquid phase It means a production method by polycondensation, and if necessary, baking or reduction treatment may be performed.

  The “metal” of the metal alkoxide, metal halide, metal salt or metal used in the present invention is generally “transition metal (transition metal)” in addition to “metals” defined in the periodic table or the like. All elements of “Metals”, all elements of “lanthanoid”, all elements of “actinoid”, and boron, silicon defined as “Non Metals” . In particular, when manufacturing by the Sol-Gel method, a phosphor precursor solution or a liquid containing primary particles is patterned on a transparent substrate by a printing method, an inkjet method, or the like, followed by crystallization treatment such as baking or reduction treatment or high brightness. Processing may be performed.

  The inorganic phosphor is preferably a rare earth complex phosphor. Thereby, the color conversion efficiency is improved and the power consumption of the organic EL element can be further reduced.

  Examples of rare earth complex phosphors include those having Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, etc. as rare earth metals. The ligand may be either aromatic or non-aromatic, and a compound represented by the following general formula (C) is preferable.

Formula _{(C) Xa- (L x)} - (L y) n - (L z) -Ya
[Wherein, L _x , L _y , and L _z each independently represent an atom having two or more bonds, n represents 0 or 1, and Xa represents an atom that can be coordinated to the adjacent position of L _x. represents a substituent having, Ya represents a substituent having a coordinating an atom at the adjacent position to L _Z. Further, any part of Xa and L _X may be condensed with each other to form a ring, and any part of Ya and L _z may be condensed with each other to form a ring, and L _x and L _z May be condensed with each other to form a ring, and at least one aromatic hydrocarbon ring or aromatic heterocyclic ring is present in the molecule. _{However, Xa- (L x) - (} L y) n - (L z) -Ya is beta-diketone derivative and beta-keto ester derivative, beta-ketoamide derivative or an oxygen atom of the ketone sulfur atom or -N (R ₂₀₁ )-, (R ₂₀₁ represents a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group), crown ether, azacrown ether, thiacrown ether or crown ether In the case of a crown ether in which an oxygen atom is replaced with any number of sulfur atoms or —N (R ₂₀₁ ) —, there may be no aromatic hydrocarbon ring or aromatic heterocyclic ring. ]
In the general formula (C), the coordinateable atoms represented by Xa and Ya are specifically an oxygen atom, a nitrogen atom, a sulfur atom, a selenium atom, and a tellurium atom, particularly an oxygen atom, a nitrogen atom, A sulfur atom is preferred.

In the general formula (C), the atom having two or more bonds represented by L _x , L _y , and L _z is not particularly limited, but typically, a carbon atom, an oxygen atom, a nitrogen atom, A silicon atom, a titanium atom, etc. are mentioned, A preferable one is a carbon atom.

  Specific examples of the rare earth complex phosphor represented by the general formula (C) are shown below, but the present invention is not limited thereto.

  Next, the color conversion filter will be described.

  A color conversion filter is a wavelength conversion element used to convert the color of a light source (emission color) to a desired color. Basically, the wavelength is longer than the maximum maximum wavelength of the light source by 10 nm or longer. This is a wavelength conversion element that can be converted. Specific applications include filters for full-color displays described in JP-A Nos. 3-152897, 9-245511, 11-297477, etc. (from blue light sources to green and red By converting them into stripes, they are arranged in stripes to make color conversion filters that can emit blue, green, and red light, and white light emission filters for lighting and liquid crystal display backlights (400-700 nm in the visible region). Color conversion filters that emit a wide range of light), partial emission filters for neon signs and automotive instruments (necessary colors where needed) And color conversion filter) for displaying can be mentioned as a typical example. The color conversion filter is useful when used as a color conversion layer of an organic EL element.

  As the general formula (A) contained in the color conversion filter, it is preferable to use the specific example of the general formula (A) described above, whereby the color can be efficiently converted.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated in detail, the aspect of this invention is not limited to this.

Example 1 Synthesis of Organic Compound Example 1-1 Synthesis of Organic Compound (XVI-1) 5.0 g of tris (2,5-dimethyl, 4-bromo) amine was dissolved in 300 cc of dry tetrahydrofuran under a nitrogen atmosphere and dried. Cooled to -78 degrees with ice / acetone. To this reaction solution, 30 cc of n-butyllithium n-hexane solution was added dropwise over 30 minutes. After stirring for 1 hour, 5 g of dry ice was quickly added. Then, after stirring for a while, tetrahydrofuran was distilled off under reduced pressure, ethyl acetate and water were added, and the organic layer was extracted. After drying over magnesium sulfate, ethyl acetate was distilled off under reduced pressure and recrystallized with acetic acid and methanol to obtain 3.0 g of tris (2,5-dimethyl, 4-carboxy) amine (yield 74%).

  Next, 3.0 g of tris (2,5-dimethyl, 4-carboxy) amine and 2.7 g of 2,3-diaminofuran were dissolved in 20 g of polyphosphoric acid under a nitrogen atmosphere. The reaction solution was heated and stirred at 200 degrees for 4 hours. Thereafter, the reaction solution was drained, adjusted to pH = 8.0 with sodium carbonate, and filtered. The obtained crystals were washed with dimethylformamide and filtered to obtain 2.7 g of tris (2,5-dimethyl, 4-benzimidazolyl) amine (yield 62%).

  1.0 g of tris (2,5-dimethyl, 4-benzimidazolyl) amine was heated in 100 cc together with 1.0 g of potassium carbonate and 0.8 g of n-bromobutane in 20 cc NN-dimethylacetamide and reacted for 2 hours. . Then, water was poured, ethyl acetate and water were added to the obtained crystals, and the organic layer was extracted. After drying over magnesium sulfate, ethyl acetate was distilled off under reduced pressure. Purification by column chromatography with a ratio of ethyl acetate to toluene of 7: 3 gave 0.7 g of the desired compound (XVI-1).

  When the fluorescence spectrum of the target organic compound was measured in acetonitrile, it was found that the fluorescence wavelength was 417 nm (excitation wavelength was 355 nm), and the fluorescence quantum yield was 0.24.

  The ionization potential was 5.70 eV, the band gap was 3.12 eV, and the electron affinity was 2.58 eV.

Example 1-2 Synthesis of Organic Compound XVII-1 5.0 g of tris (2,5-dimethyl, 4-bromo) amine was dissolved in 300 cc of dry tetrahydrofuran under a nitrogen atmosphere and cooled to -78 degrees with dry ice / acetone. did. To this reaction solution, 30 cc of n-butyllithium n-hexane solution was added dropwise over 30 minutes. After stirring for 1 hour, 5 g of dry ice was quickly added. Then, after stirring for a while, tetrahydrofuran was distilled off under reduced pressure, ethyl acetate and water were added, and the organic layer was extracted. After drying over magnesium sulfate, ethyl acetate was distilled off under reduced pressure and recrystallized with acetic acid and methanol to obtain 3.0 g of tris (2,5-dimethyl, 4-carboxy) amine (yield 74%).

  Next, 3.0 g of tris (2,5-dimethyl, 4-carboxy) amine and 3.9 g of orthophenylenediamine were dissolved in 20 g of polyphosphoric acid under a nitrogen atmosphere. The reaction solution was heated and stirred at 200 degrees for 4 hours. Thereafter, the reaction solution was drained, adjusted to pH = 8.0 with sodium carbonate, and filtered. The obtained crystals were washed with dimethylformamide and filtered to obtain 2.7 g of tris (2,5-dimethyl, 4-benzimidazolyl) amine (yield 62%).

1.0 g of tris (2,5-dimethyl, 4-benzimidazolyl) amine was heated in 100 cc together with 1.0 g of potassium carbonate and 0.8 g of n-bromobutane in 20 cc NN-dimethylacetamide and reacted for 2 hours. . Then, water was poured, ethyl acetate and water were added to the obtained crystals, and the organic layer was extracted. After drying over magnesium sulfate, ethyl acetate was distilled off under reduced pressure. Purification by column chromatography with a ratio of ethyl acetate to toluene of 7: 3 gave 1.0 g of the desired organic compound (XVI-1). (Yield 80%)
By NMR and mass spectrum, it was confirmed to be the target organic compound (XVII-1).

  When the fluorescence spectrum of the target organic compound was measured in acetonitrile, it was found that the fluorescence wavelength was 413 nm (excitation wavelength was 348 nm), the fluorescence quantum yield was 0.27, and blue-violet light was emitted with high brightness.

  The ionization potential was 5.72 eV, the band gap was 3.27 eV, and the electron affinity was 2.45 eV.

Example 1-3 Synthesis of Organic Compound (XVIII-1) In the same manner as in Example 10 except that 3.9 g of orthophenylenediamine was replaced with 4.5 g of 3,4-diaminopyridine in Example 1-1 above. Then, 0.8 g of compound (XVIII-1) was synthesized. When the fluorescence spectrum of the target compound was measured in acetonitrile, it was found that the fluorescence wavelength was 406 nm (excitation wavelength was 349 nm), the fluorescence quantum yield was 0.18, and blue-violet light was emitted with high brightness.

  The ionization potential was 5.78 eV, the band gap was 3.24 eV, and the electron affinity was 2.54 eV.

Example 1-4 Synthesis of Organic Compound (XIX-1) The synthesis route is shown below.

  Compound (12-1) (5.0 g) was dissolved in acetonitrile (200 cc), compound (12-2) (12.0 g) was added, and the mixture was stirred at room temperature for 8 hours. Then, it was ice-cooled, filtered and dried to obtain 7.9 g of a white compound (12-3).

  Compound (12-3) (7.0 g) was dissolved in 200 cc of methanol, hydroxylamine hydrochloride (2.8 g) and sodium acetate (3.3 g) dissolved in water (50 cc) were added, and the mixture was heated to reflux for 1 hour. Methanol was distilled off under reduced pressure and filtered to obtain 6.2 g of white crystals (amide oxime form).

  4.0 g of the amide oxime was dissolved in 300 cc of toluene, and 1.5 g of pyridine was added, followed by ice cooling. To this reaction solution, 3.4 g of tosylic chloride was added dropwise over 10 minutes. Thereafter, the mixture was heated to reflux for 5 hours, and then allowed to cool overnight to precipitate crystals. The crystals were filtered and recrystallized from methanol to obtain 2.8 g of Compound (12-4). Compound (12-4) (2.5 g) was dissolved in tetrahydrofuran (200 cc) and heated to reflux with 2.0 g of potassium carbonate and 2.1 g of n-bromobutane for 2 hours. Then, tetrahydrofuran was depressurizingly distilled, ethyl acetate and water were added, and the organic layer was extracted. After drying over magnesium sulfate, ethyl acetate was distilled off under reduced pressure. Recrystallization from acetonitrile gave 2.7 g of an organic compound (XIX-1).

  When the fluorescence spectrum of the above-mentioned target compound was measured in acetonitrile, it was found that the fluorescence wavelength was 412 nm (excitation wavelength was 354 nm), the fluorescence quantum yield was 0.31, and blue-violet light was emitted with high brightness.

  The ionization potential was 5.63 eV, the band gap was 3.15 eV, and the electron affinity was 2.48 eV.

Example 1-5 Synthesis of Organic Compound (XX-1) The synthesis route is shown below.

Compound (14-1) 8.0g was melt | dissolved in 150 cc acetic acid, and phenylhydrazine 4.7g was dripped at 0 degree | times. After completion of dropping, the mixture was stirred at 100 degrees for 1 hour. Thereafter, ethyl acetate and water were added, and the organic layer was extracted. After drying over magnesium sulfate, ethyl acetate was distilled off under reduced pressure. Next, the residue was purified by column chromatography with a ratio of ethyl acetate to hexane of 1:13 to obtain 4.2 g of compound (14-2). (Yield 38%)
Next, 3.0 g of compound (14-2) and 2.7 g of compound (14-3) were dissolved in 100 cc of tetrahydrofuran, and 3.0 g of triethylamine was added. The reaction was heated and stirred for 24 hours. Then, tetrahydrofuran was depressurizingly distilled, ethyl acetate and water were added, and the organic layer was extracted. After drying over magnesium sulfate, ethyl acetate was distilled off under reduced pressure. Next, the residue was purified by column chromatography with a ratio of ethyl acetate to hexane of 1: 9 to obtain 2.1 g of an organic compound (XX-1). (Yield 40%)
When the fluorescence spectrum of the target organic compound was measured in acetonitrile, the fluorescence wavelength was 403 nm (excitation wavelength was 334 nm), and the fluorescence quantum yield was 0.65.

  The ionization potential was 5.53 eV, the band gap was 3.30 eV, and the electron affinity was 2.23 eV.

Example 2 Synthesis of Inorganic Phosphor Example 2-1-1 Synthesis of Red Luminescent Fine Particle Inorganic Phosphor (RL-11) Mg ₄ GeO ₆ : Mn ⁴⁺ 150 ml of ethanol in ammonia water containing 0.016 mol of ammonia And 150 ml of water were added to prepare an alkaline solution.

  Further, a solution obtained by dissolving 10.0 g (0.04 mol) of tetraethoxygermanium and 0.030 g (0.2 mmol) of manganese sulfate (IV) in 150 ml of ethanol was dropped into the alkaline solution at a dropping rate of about 1 ml at room temperature. The mixture was added with stirring at / min to prepare a sol solution. The obtained sol was concentrated about 15 times (about 30 ml) with an evaporator, and 295 ml of a 0.3 mol / l magnesium nitrate aqueous solution was added thereto to cause gelation.

The obtained wet gel was aged in a sealed container at 60 ° C. overnight. Thereafter, the mixture was stirred and dispersed in ethanol (about 300 ml), collected by suction filtration using filter paper (Advantec 5A), and dried at room temperature. The dried gel was heat-treated at 1000 ° C. for 2 hours in a 5% H 2 -N 2 atmosphere to obtain 2.7 g of an inorganic phosphor RL-11 (Mg ₄ GeO ₆ : Mn ⁴⁺ ) that glows red under sunlight.

  Conventionally, a solid phase method or a melting method has been employed for the production of inorganic phosphors. However, in these methods, the distribution of each metal oxide is non-uniform and the reaction is not uniform, so the composition of the obtained inorganic phosphor becomes non-uniform and it is difficult to stabilize its characteristics. . Furthermore, since impurities are likely to be mixed and the characteristics are deteriorated, a method of manufacturing an inorganic phosphor having a uniform composition and high purity by a sol-gel method using a metal alkoxide was employed.

The component composition of RL-11 was analyzed by XRD spectrum. As a result, it was found that the main component was Mg ₄ GeO ₆ , and the minor components contained were Mg ₃ GeO ₅ and Mg ₅ GeO ₇ .

  It was found that RL-11 is a phosphor that emits red light of 660 nm (excitation light 420 nm) when measured in acetonitrile with an average particle diameter of 0.85 μm and an emission maximum wavelength. Since RL-11 is an inorganic phosphor, it has a longer lifetime than an organic phosphor. It is a substance that can efficiently convert 350 to 450 nm light into red and has a long lifetime, and is therefore useful as an inorganic phosphor added to the conversion layer of an organic EL element.

Example 2-1-2 Synthesis of inorganic phosphor (RL-12) K ₅ Eu _2.5 (WO ₄ ) _6.25 Ammonia water containing 0.016 mol of ammonia was added to 150 ml of ethanol and 150 ml of water. An alkaline solution was prepared.

  Further, a solution prepared by dissolving 23.2 g (0.04 mol) of tungsten (IV) acetylacetonate complex and 9.7 g (0.02 mol) of europium (III) acetylacetonate complex dihydrate in 150 ml of ethanol at room temperature. Under stirring, the mixture was added to the alkaline solution at a dropping rate of about 1 ml / min with stirring to prepare a sol solution. The obtained sol was concentrated to about 15 times (30 ml) with an evaporator, and 295 ml of a 0.3 mol / l potassium nitrate aqueous solution was added thereto for gelation.

The obtained wet gel was aged in a sealed container at 60 ° C. overnight. Thereafter, the mixture was dispersed with stirring in ethanol (about 300 ml), collected by suction filtration using filter paper (Advantec 5A), and dried at room temperature. The dried gel was aged in a 5% H2-N2 atmosphere at 1000 ° C. for 2 hours, and glowed red under sunlight. RL-12 (K ₅ Eu _2.5 (WO ₄ ) _6.25 ) 3.2 g was obtained.

  It was found that RL-12 is a phosphor that emits red light having an average particle diameter of 1.15 μm and an emission maximum wavelength of 615 nm (excitation light of 394 nm).

Example 2-2 Synthesis of Inorganic Phosphor (GL-10) Ba ₂ SiO ₄ : Eu ²⁺ An alkaline solution was prepared by adding 150 ml of ethanol and 150 ml of water to ammonia water containing 0.016 mol of ammonia.

  Further, a solution prepared by dissolving 8.33 g (0.04 mol) of tetraethoxysilane and 0.097 g (0.2 mmol) of europium (III) acetylacetonate complex dihydrate in 150 ml of ethanol was added to the alkali at room temperature. The solution was added to the solution while stirring at a dropping rate of about 1 ml / min to prepare a sol solution. The obtained sol was concentrated about 15 times (about 30 ml) with an evaporator, and 295 ml of 0.3 mol / l barium nitrate aqueous solution was added thereto to cause gelation.

The obtained wet gel was aged in a sealed container at 60 ° C. overnight. Thereafter, the mixture was stirred and dispersed in ethanol (about 300 ml), collected by suction filtration using filter paper (Advantec 5A), and dried at room temperature. 1. The dried gel is an inorganic phosphor GL-10 (Ba ₂ SiO ₄ : Eu ²⁺ 0.005) that is heat-treated at 1000 ° C. for 2 hours in a 5% H ₂ —N ₂ atmosphere and glows light green under sunlight. 7 g was obtained.

The component composition of GL-10 was analyzed by XRD spectrum. As a result, it was found that the main component was Ba ₂ SiO ₄ , and the minor components included were BaSiO ₃ and Ba ₃ SiO ₅ .

  It was found that GL-10 was a phosphor that emitted green light with an average particle diameter of 1.05 μm and an emission maximum wavelength of 510 nm (excitation light 405 nm).

Example 2-3 Inorganic phosphor (BL-3) Synthesis of BaMgAl ₁₀ O ₁₇ : Eu ^{2+ In} Example 2-2, tetraethoxysilane was changed to 8.2 g of isopropoxyl aluminum, and an aqueous barium nitrate solution was used. A blue-emitting inorganic phosphor (BL-3) (average particle size 0.90 μm, maximum emission wavelength 432 nm (excitation light 375 nm) was used in the same manner except that the mixture was changed to 300 ml of a 1: 1 mixed aqueous solution of barium nitrate and magnesium nitrate. )).

Example 3 Production and Evaluation of Color Conversion Filter Example 3-1 Production of Color Conversion Filter Using Inorganic Phosphor Phosphorus 0.16 g Aerosil with an average particle diameter of 5 nm and ethanol 15 g and γ-glycidoxypropyltriethoxysilane 0 .22 g was added and the mixture was stirred at room temperature for 1 hour. This mixture and 20 g of (RL-10) prepared in Example 2-1 were transferred to a mortar, thoroughly mixed, and then heated in an oven at 70 ° C. for 2 hours and further in an oven at 120 ° C. for 2 hours to modify the surface. (RL-11) was obtained.

  Similarly, the surface modification of (GL-10) produced in Example 2-2 and (BL-3) produced in Example 2-3 was also performed.

  30 g of butyral (BX-1) dissolved in a mixed solution (300 g) of toluene / ethanol = 1/1 was added to 10 g of the above-described surface modification (RL-11), and the mixture was stirred and then wet film thickness was added. It was coated on glass at 200 μm. The obtained coated glass was heated and dried in an oven at 100 ° C. for 4 hours to prepare the color conversion filter (F-1) of the present invention.

  In the same manner, the color conversion filters (F-2) and (RL-12) coated with (GL-10) are coated with the color conversion filters (F-2) and (RL-12) coated with (BL-3). The provided color conversion filter (F-9) was created. (F-1) and (F-9) had an excitation wavelength at 350 to 450 nm.

Example 3-2 Preparation of Color Conversion Filter Using Rare Earth Complex Phosphor The rare earth complex fluorescence of the present invention was added to 30 g of butyral (BX-1) dissolved in a mixed solution (300 g) of toluene / ethanol = 1/1. 3 g of the body (RE-17) was dissolved, applied onto a polyethersulfone (PES) film having a thickness of 80 μm with a wet film thickness of 150 μm, and dried with warm air to prepare a color conversion filter (F-4).

  Color conversion filters (F-5) and (F-6) were prepared in the same manner except that RE-17 was changed to the substances shown in Table 1.

Example 3-3 Creation of Color Conversion Filter Using Organic Phosphor Color conversion filter (F-7) was prepared in the same manner except that RE-17 in Example 3-2 was replaced with the substance shown in Table 1. ), (F-8).

Example 3-4 Evaluation of Color Conversion Filter After patterning a substrate (NA-45 manufactured by NH Techno Glass Co., Ltd.) having a 150 nm ITO film formed on glass as an anode, a transparent support substrate provided with this ITO transparent electrode was formed. Ultrasonic cleaning with isopropyl alcohol, drying with dry nitrogen gas, and UV ozone cleaning were performed for 5 minutes. This transparent support substrate is fixed to a substrate holder of a commercially available vacuum vapor deposition apparatus. Meanwhile, 200 mg of m-MTDATXA is put into a molybdenum resistance heating boat, and 200 mg of an organic compound (VIII-1) is put into another molybdenum resistance heating boat. Furthermore, 200 mg of BC was put into another resistance heating boat made of molybdenum and attached to a vacuum deposition apparatus. Next, after depressurizing the vacuum tank to 4 × 10 ⁻⁴ Pa, energizing the heating boat containing m-MTDATXA, heating to 220 ° C., and supporting transparent at a deposition rate of 0.1 to 0.3 nm / sec. It vapor-deposited on the board | substrate and provided the positive hole injection layer with a film thickness of 60 nm. Furthermore, the heating boat containing (VIII-1) was energized and heated to 220 ° C., and deposited on the hole injection layer at a deposition rate of 0.1 to 0.3 nm / sec to emit light with a thickness of 40 nm. A layer was provided. Further, the heating boat containing BC was energized and heated to 250 ° C., and deposited on the light emitting layer at a deposition rate of 0.1 nm / sec to provide an electron injection layer having a thickness of 20 nm. In addition, the substrate temperature at the time of vapor deposition was room temperature.

Next, a vacuum chamber is opened, and a stainless steel rectangular perforated mask is placed on the electron injection layer. On the other hand, 3 g of magnesium is placed in a molybdenum resistance heating boat, and 0.02 of silver is placed in a tungsten vapor deposition basket. 5 g was added and the vacuum chamber was again depressurized to 2 × 10 ⁻⁴ Pa, and then the magnesium-containing boat was energized to deposit magnesium at a deposition rate of 1.5 to 2.0 nm / sec. Was heated, and silver was vapor-deposited at a vapor deposition rate of 0.1 nm / sec to form a counter electrode made of the mixture of magnesium and silver, thereby producing an electroluminescent device.

  A color conversion filter (F-1) to (F-9) was used as the color conversion layer of the organic EL layer, and a voltage of DC 8 V was applied to the anode and the cathode.

  Table 2 shows values and emission colors based on the CIE chromaticity coordinates (JIS Z 8701) of each color conversion filter at that time.

  Furthermore, this time, the brightness | luminance which light-emits from a color conversion filter was measured by applying 12-V DC voltage in dry nitrogen gas atmosphere.

  Next, the color conversion filters (F-1) to (F-9) left for 3 days in an environment of 60 degrees 40% and the color conversion filter irradiated for 3 days with a 100,000 lux xenon fade meter are left standing, The luminance emitted from the color conversion filter that had been deteriorated during storage was measured.

  Table 2 shows the relative value of each color conversion filter when the luminance emitted from the color conversion filter that has not been deteriorated during storage is 100.

From Table 2,
It can be seen that the inorganic phosphor is superior in thermal stability and light stability to the color conversion material than the organic phosphor. In particular, since the color conversion filters (F-1) and (F-9) are very excellent in thermal stability and light stability, they may have a very long life when used in a color conversion layer of an organic EL element. Can be useful.

Example 4 Electroluminescence element No. Preparation of 1 to 34 A carbon black-containing methacrylate resist (CK2000 manufactured by Fuji Hunt Electronics Technology Co., Ltd.) was spin-coated on one side of a 100 mm × 100 mm × 1.1 mm non-alkali glass supporting substrate (Corning 7059) at 200 ° C. A black solid film having a thickness of about 2 μm was formed by baking. Next, the surface of the substrate opposite to the black film was subjected to IPA cleaning and UV cleaning, and then fixed to a substrate holder of a vacuum deposition apparatus. The deposition source is a molybdenum resistance heating boat charged with m-MTDATXA as a hole injection material, compound (IV-1) as a light emitting material, BC as an electron injection material, and Ag as a second metal of the electrode, and a tungsten filament. In addition, Mg was mounted on a molybdenum boat as an electron injecting metal of the electrode. Then, after depressurizing the vacuum chamber to 5 × 10 ⁻⁷ torr, through a mask that can be formed into stripes with a pitch of 1.5 mm (1.4 mm line 0.1 mm gap) in a range of 72 mm × 72 mm, First, an electrode pattern was formed, and then from an electron injection layer to a hole injection layer through a mask capable of solid film formation in a range of 72 mm × 72 mm. In addition, when sequentially laminating the hole injection layer from the electrode, it was performed by evacuation once without breaking the vacuum on the way. First, Mg and Ag were vapor-deposited simultaneously as an electrode. That is, Mg has a deposition rate of 1.3 to 1.4 nm / s, Ag has a deposition rate of 0.1 nm / s, and a film thickness of 200 nm. Next, as the electron injection layer, BC is deposited at a deposition rate of 0.1 to 0.3 nm / s and a film thickness is 20 nm. As the light emitting layer, an organic compound (IV-1) is deposited at a deposition rate of 0.1 to 0.3 nm / s. As a hole injection layer with a film thickness of 50 nm, m-MTDATXA was deposited under conditions of a deposition rate of 0.1 to 0.3 nm / s and a film thickness of 40 nm. Next, this substrate was moved to a sputtering apparatus, and ITO was used as a transparent electrode having a thickness of 120 nm and 20 Ω / □ at room temperature, and a stripe of 4.5 mm pitch (4.0 mm line 1.0 mm gap) in a range of 72 mm × 72 mm. An organic EL element was manufactured by forming a film through a mask that can be formed into a film. Here, the electrode and the transparent electrode were crossed, and the mask was arranged so that the terminal of each electrode could be taken. Next, on the periphery of the crossing range of the electrode on the substrate and the transparent electrode (72 mm × 72 mm range), using a dispenser, an epoxy two-component mixed adhesive (CIBA-GEIGY, Araldide) is about 1 mm. It was applied with a gap in the width. Next, a 100 mm × 100 mm × 0.15 mm non-alkali glass substrate (Corning 7059) was bonded to the substrate C to cure the adhesive. Next, under a nitrogen atmosphere, fluorinated hydrocarbon (Fluorinert manufactured by 3M Corporation in the United States) was injected into the gap between the glass substrate bonded to the support substrate through the gap between the previously cured adhesive with an injection needle. Next, the adhesive was further filled in the gap between the adhesives and cured.

  On this substrate, a color conversion filter (F-3) as a blue color conversion layer, a color conversion filter (F-2) as a green color conversion layer, and a color conversion filter (F-1) as a red color conversion layer at 1.5 mm intervals, respectively. The organic EL element No. 1 was produced.

  Further, the organic compound (IV-1) is replaced with the compound shown in Table 3, and the color conversion filter shown in Table 3 is provided as a color conversion layer in place of the color conversion filters F-1, F-2 and F-3. Thus, organic EL elements NO.2 to NO.34 were prepared.

  The band gap was obtained by measuring the absorption spectrum of the deposited film when an organic compound was deposited on glass to a thickness of 100 nm and converting the wavelength at the absorption edge into eV.

  The compound that was not synthesized in Example 1 was synthesized and used according to the method described in Japanese Patent Application No. 11-341923 (Japanese Patent Laid-Open No. 2001-160488).

Example 5 Organic electroluminescence element No. 1-34 Example 5-1 Organic electroluminescent element No. Evaluation of color conversion efficiency of 1 to 34 and half-life time of luminance after continuous light emission Each of the electroluminescence elements NO.1 to NO.34 is continuously lit by applying a 12 V DC voltage in a dry nitrogen gas atmosphere at a temperature of 23 ° C. The light emission efficiency at the start of lighting (lm / W) and the time for halving the luminance were measured using a Minolta CS-1000. Luminous efficiency was expressed as a relative value when the luminous efficiency of sample 1 was set to 100, and the time when the luminance was reduced by half was expressed as a relative value where the time when the luminance of sample 1 was reduced by half was set to 100. The results are shown in Table 4.

  From Table 4, it was found that the electroluminescence element of the present invention has excellent luminous efficiency because the color conversion layer uses an inorganic phosphor instead of an organic phosphor. Moreover, it turned out that there exists a difference by an organic compound in making an inorganic compound light-emit efficiently. In the organic EL device of the present invention, the organic compound contained in the light emitting layer has a long lifetime.

Example 5-2 Organic electroluminescence device No. 1-34 Evaluation of the highest possible luminance Organic electroluminescent element No. A DC voltage of 10 volts was applied to 1 to 34, and the light emission luminance and the maximum light emission wavelength of each color conversion layer were measured using a Minolta CS-1000. The highest reached luminance is the organic EL element No. It was expressed as a relative value when the maximum reached luminance of 1 was 100. The results are shown in Table 5. The maximum radiant energy of the light emitting layer was measured before adding the color conversion layer.

  As is clear from Table 5, the electroluminescence device of the present invention has a high maximum attained luminance, and thus has been found to be very useful as an organic EL device.

Example 6-1 Organic electroluminescence element No. Preparation of 6-1 to 6-12 Patterning was performed on a substrate (NA-45 manufactured by NH Techno Glass Co., Ltd.) in which ITO (indium tin oxide) was formed to a thickness of 150 nm on a glass substrate of 100 mm × 100 mm × 1.1 mm as an anode. Thereafter, the transparent support substrate provided with the ITO transparent electrode was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and subjected to UV ozone cleaning for 5 minutes.

This transparent support substrate is fixed to a substrate holder of a commercially available vacuum vapor deposition apparatus. Meanwhile, 200 mg of m-MTDATXA is put into a molybdenum resistance heating board, and 200 mg of compound (I) is put into another resistance heating board made of molybdenum. Furthermore, 200 mg of bathocuproine (BC) was put in another resistance heating board made of molybdenum, and attached to a vacuum deposition apparatus. Next, after reducing the vacuum chamber to 4 × 10 ⁻⁴ Pa, energizing the heating board containing m-MTDATXA, heating to 220 ° C., and supporting transparent at a deposition rate of 0.1 to 0.3 nm / sec. It vapor-deposited on the board | substrate and provided the 33-nm-thick hole transport layer. Further, the heating board containing the compound (A) is energized, heated to 220 ° C., and deposited on the hole transport layer at a deposition rate of 0.1 to 0.3 nm / sec to emit light having a thickness of 33 nm. A layer was provided. In addition, the substrate temperature at the time of vapor deposition was room temperature.

Next, a vacuum chamber is opened, and a stainless steel rectangular perforated mask is placed on the electron injection layer. On the other hand, 3 g of magnesium is placed on a molybdenum resistance heating board, and 0.02 of silver is placed in a tungsten vapor deposition basket. 5 g was added and the vacuum chamber was again depressurized to 2 × 10 ⁻⁴ Pa, and then the magnesium-containing board was energized to deposit magnesium at a deposition rate of 1.5 to 2.0 nm / sec. Was heated, and silver was deposited at a deposition rate of 0.1 nm / sec to form a counter electrode made of the mixture of magnesium and silver, thereby producing a comparative organic electroluminescence device 6-1.

In the above, organic electroluminescent elements 6-2 to 6-14 were produced in exactly the same manner except that BC in the electron transport layer was replaced with the compounds shown in Table 6. Example 6-2 Organic electroluminescence element No. Evaluation of 6-1 to 6-14 The luminance of the samples 6-1 to 6-14 was measured and evaluated.

A voltage was applied to Sample 6-1 and current began to flow at an initial drive voltage of 5V. The maximum radiant energy of Sample 6-1 was 4 W / Sr · m ² at 9V. Table 6 shows values (relative values) of the ratios of the maximum radiant energy of Samples 6-2 to 6-14 when the maximum radiant energy of Sample 6-1 at this time is 100.

Moreover, as a result of conducting a life test on the sample 6-1 in a nitrogen gas atmosphere, the half-life of the initial radiation energy of 1 W / Sr · m ² was 840 hours. Table 6 shows values (relative values) of the ratios of the light emission lifetimes of Samples 6-2 to 6-14 when the light emission lifetime of Sample 6-1 is 100.

  The emission color was determined from the (x, y) coordinates of the CIE chromaticity coordinates.

  As is apparent from Table 6, when the organic compound used for the light emitting layer is used for the electron transport layer, the maximum radiant energy is higher and the light emission lifetime is longer, so that it is found to be very useful as an organic EL device. did.

  In addition, since the visibility varies greatly depending on the emission color, the comparison was made by radiant energy rather than luminance.

Example 7 Production of organic EL elements 7-1 to 7-14 and evaluation of maximum reached luminance and luminance half time after continuous light emission On the substrates of Samples 6-1 to 6-14 produced in Example 6-1, The sample is obtained by attaching a color conversion filter (F-B) as a blue conversion layer, a color conversion filter (FG) as a green conversion layer, and a color conversion filter (F-R) as a red conversion layer at 1.5 mm intervals. 7-1 to 7-14 were produced.

  Applying 9V DC voltage to each of Samples 7-1 to 7-14 in a dry nitrogen gas atmosphere at a temperature of 23 ° C., the emission brightness of each blue, green and red, chromaticity coordinates, and the time to reduce the brightness by half. It measured using Minolta CS-1000. The maximum reached luminance and the light emission lifetime were expressed as relative values when the maximum reached luminance and the light emission lifetime of Sample 7-1 were taken as 100. The results are shown in Table 7.

  As is clear from Table 7, the organic EL element has been found to be very useful as an organic EL element because it has the highest possible luminance and a high light emission lifetime.

Example 8 Production of organic electroluminescent elements 8-1 to 8-25 and evaluation of maximum radiant energy and light emission lifetime In the same manner as in Example 6, m-MTDATXA was formed on a transparent support substrate provided with an ITO transparent electrode. A pressure of 30 nm was deposited to form a hole transport layer. On top of that, compound (a) was deposited to 40 nm to form a light emitting layer. Subsequently, BC was deposited thereon to a thickness of 30 nm to form an electron transport layer. Subsequently, an Al / Li = 99/1 (mass%) alloy was deposited thereon to a thickness of 100 nm to form a counter electrode, whereby a comparative organic EL element 8-1 was produced.

  Further, Comparative Sample 8-2 was prepared in the same manner as Sample 8-1, except that lithium fluoride was deposited to a thickness of 0.5 nm between the electron transport layer and the aluminum layer to form a cathode buffer layer.

  In the same manner, Samples 8-3 to 8-25 were fabricated with the electron transport layer, the light emitting layer, and the cathode buffer layer as shown in Table 8.

These elements were continuously lit by applying a DC voltage of 10 V under a dry nitrogen gas atmosphere at a temperature of 23 ° C., and the maximum radiant energy (W / Sr · m ² ) at the start of lighting and the time for halving the maximum radiant energy were measured. . The maximum radiant energy is expressed as a relative value when the maximum radiant energy of 8-1 is 100, and the time to halve the maximum radiant energy is the time to halve the maximum radiant energy of sample 8-1. It was expressed as a relative value with the time for energy halving as 100. The results are shown in Table 8.

  The emission color was determined from the (x, y) coordinates of the CIE chromaticity coordinates.

  From these results, the following can be said.

  1) When the cathode buffer layer is laminated, the above compound is more effective than the conventional compound obtained by laminating lithium fluoride.

  2) It is more effective to use the organic compound used in the organic EL device for the electron transport layer and further stack a cathode buffer layer.

  3) It is more effective when an organic compound used in the organic EL device is used in combination in the electron transport layer and the light emitting layer, and a cathode buffer layer is further laminated.

  As a result, it was possible to obtain an organic EL device that emits blue-violet light and has high luminance and long life.

Example 9 Production of organic electroluminescent elements 9-1 to 9-29 and evaluation of maximum luminance and light emission lifetime In the same manner as in Example 6, m-MTDATXA was applied to a transparent support substrate provided with an ITO transparent electrode. 30 nm was vapor-deposited to form a hole transport layer. On top of that, in addition to the compound (I), which is an organic compound, 5% by mass of a fluorescent material (dopant) (DA) with respect to the compound (I) was co-evaporated to 40 nm to form a light emitting layer. Subsequently, BC was deposited thereon to a thickness of 30 nm to form an electron transport layer. Subsequently, a comparative sample 9-1 was prepared by depositing 100 nm of aluminum thereon to form a counter electrode.

  Further, Comparative Sample 9-2 was prepared in the same manner as Sample 9-1 except that lithium fluoride was deposited to a thickness of 0.5 nm between the electron transport layer and the aluminum layer to form a cathode buffer layer.

  Similarly, Samples 9-3 to 9-29 were fabricated by configuring the electron transport layer, the light emitting layer, the fluorescent material (dopant), and the cathode buffer layer as shown in Table 9.

These samples were continuously lit by applying a 10 V DC voltage in a dry nitrogen gas atmosphere at a temperature of 23 ° C., and the maximum luminance (cd / m ² ) at the start of lighting and the time for halving the maximum luminance were measured. The maximum luminance was expressed as a relative value when the maximum luminance of 9-1 was 100, and the time for the maximum luminance to be halved was expressed as a relative value with the time for the maximum luminance of the sample 9-1 being halved as 100. The results are shown in Table 9.

  From these results, the following is clear.

  1) It is more effective to use an organic compound used in the organic EL element for the electron transport layer and introduce a dopant to the light emitting layer.

  2) It is more effective to use the organic compound used in the organic EL device in the electron transport layer and the light emitting layer, to further stack a cathode buffer layer, and to introduce a dopant into the light emitting layer.

  As a result, an organic EL device having high brightness and long life could be obtained.

Example 10 Preparation of organic electroluminescence elements 10-1 to 10-26 and evaluation of maximum radiant energy and emission lifetime In the same manner as in Example 6, m-MTDATXA was formed on a transparent support substrate provided with an ITO transparent electrode. 30 nm was vapor-deposited to form a hole transport layer. On top of that, TAZ was vapor-deposited to 40 nm to form a light emitting layer. Subsequently, BC was deposited thereon to a thickness of 30 nm to form an electron transport layer. Subsequently, an alloy of Al / Li = 99/1 (mass%) was deposited thereon to a thickness of 100 nm to prepare a counter sample 10-1.

  Samples 10-2 to 10-26 were prepared in exactly the same manner except that TAZ in the light emitting layer was replaced with the compounds shown in Table 10 above.

These elements were continuously lit by applying a DC voltage of 10 V in a dry nitrogen gas atmosphere at a temperature of 23 ° C., and the maximum radiant energy (W / Sr · m ² ) at the start of lighting and the time for halving the maximum radiant energy were measured. . The maximum radiant energy is expressed as a relative value when the maximum radiant energy of 10-1 is 100, and the time when the maximum radiant energy is halved is expressed as a relative value when the time when the maximum radiant energy of Sample 10-1 is halved is 100. did. The results are shown in Table 10.

  The emission color was determined from the (x, y) coordinates of the CIE chromaticity coordinates.

  As is clear from Table 10, the organic EL device of the present invention was found to be very useful as an organic EL device because of its high maximum radiant energy and long emission lifetime. As a result, it was possible to obtain an organic EL device that emits blue-violet light with high brightness and long life.

  Although the comparative sample 10-1 emitted blue-violet, since the molecular weight was as small as less than 600, it was found that the emission life and the like were inferior because the compound that emitted light was deteriorated with voltage application.

In addition, since the visibility varies greatly depending on the emission color, the comparison was made by radiant energy rather than luminance.
Example 11 Electroluminescence element No. Preparation of 11-1 to 11-19 and evaluation of maximum radiant energy and light emission lifetime In the same manner as in Example 6, m-MTDATXA was deposited to a thickness of 30 nm on a transparent support substrate provided with an ITO transparent electrode, and hole transport was performed. Layered. On top of this, compound (a) was deposited to 40 nm to form a light emitting layer. Subsequently, BC was deposited thereon to a thickness of 30 nm to form an electron transport layer. Subsequently, an organic EL device 11-1 for comparison was produced by depositing an alloy having a mass% ratio of aluminum and lithium of 80:20 to 100 nm thereon to form a counter electrode.

  Organic EL elements 11-2 to 11-19 were produced in the same manner as described above except that the compound (A) in the light emitting layer was replaced with the compounds shown in Table 11.

Using these elements as cathodes, continuous lighting is performed by applying a DC voltage of 10 V in a dry nitrogen gas atmosphere at a temperature of 23 degrees, and the maximum radiant energy (W / sr · m ² ) at the start of lighting and the time to halve the maximum radiant energy It was measured. The maximum radiant energy is expressed as a relative value when the maximum radiant energy of 11-1 is 100, and the time when the maximum radiant energy is halved is expressed as a relative value when the time when the maximum radiant energy of the sample 11-1 is halved is 100. did.

  Further, the samples 11-1 to 11-18 were evaluated in the same manner in the case where the counter electrode made of aluminum / lithium = 99: 1 (mass%) was used as the cathode. The results are shown in Table 11.

  The emission color was determined from the (x, y) coordinates of the CIE chromaticity coordinates.

  As is apparent from Table 11, the electroluminescence device using the compound of the preferred embodiment in the light emitting layer has a high maximum radiant energy and a long emission lifetime, and thus has been found to be very useful as an organic EL device. . In particular, it was found that when the cathode configuration was aluminum / lithium = 99: 1 (mass%), the emission lifetime was significantly improved.

In addition, since the visibility differs greatly depending on the emission color, the comparison was made with the radiant energy instead of the luminance.
Example 12 Organic electroluminescence element No. Evaluation of Maximum Achievable Luminance of 12-1 to 12-19 and Luminance Half-Time after Continuous Light Emission No. 1 of the organic EL device prepared in Example 11 On the substrate of 11-1 to 11-19, a color conversion filter (FB) as a blue conversion layer, a color conversion filter (FG) as a green conversion layer, and a color conversion filter (FR) as a red conversion layer are spaced at 1.5 mm intervals. The organic EL element No. 12-1 to 12-19 were prepared.

  The cathode was evaluated for a case where a counter electrode composed of aluminum / lithium = 80: 20 (mass%) and aluminum / lithium = 99: 1 (mass%) was used as the cathode.

  Organic EL element No. Apply a 9V DC voltage to each of 12-1 to 12-19 in a dry nitrogen gas atmosphere at a temperature of 23 ° C., and set the blue, green, and red emission luminances, the chromaticity coordinates, and the time to reduce the luminance by half. It measured using CS-1000 made. The maximum luminance and emission lifetime are as follows. It was expressed as a relative value when the maximum reached luminance and the light emission lifetime of 12-1 (the cathode is aluminum / lithium = 80: 20 (mass%)) are defined as 100. The results are shown in Table 12.

  As is clear from Table 12, the above electroluminescent device was found to be very useful as an organic EL device because of its highest ultimate luminance and high emission lifetime. In particular, it was found that when the cathode configuration was aluminum / lithium = 99: 1 (mass%), the emission lifetime was significantly improved.

DESCRIPTION OF SYMBOLS 1 Light emitting layer 2 Anode 3 Cathode 4 Color conversion layer 5 Glass substrate

Claims (1)

An organic electroluminescence device comprising a cathode, an anode, and a light emitting layer, wherein the light emitting layer contains an organic compound represented by the following general formula (XVII).
(In the formula, R _e1 , R _e2 and R _e3 each independently represents a hydrogen atom. X ₄ , X ₅ and X ₆ each represent —NR _f —, an oxygen atom or a sulfur atom, and L ₄ , L ₅ , L ₆ represents a phenylene group, a pyridylene group, or a naphthylene group that may have a methyl group as a substituent, R _f represents an alkyl group that may be substituted with a fluorine atom, k ₄ , k ₅ , k ₆ represents 4.)