JP2002329578A - Organic electroluminescent element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide blue color and white color luminescent elements with high color purity and high durability. SOLUTION: White color light is emitted by utilizing lights of blue color and orange color of complementary colors, an organic compound layer 200 is placed between an anode 12 and a cathode 14, and the organic compound layer 200 has a luminescent layer containing an organic compound represented by chemical formula i (in the formula R21 -R26 represent an optional substituent group, q21 -q23 represent an integer of 0-9) and a luminescent layer containing an organic compound represented by a chemical formula 3 in which at least two of R1 -R7 in the formula are a substituent group of a chemical formula 4. The luminescent layer is formed by doping as a guest material the compound represented by the chemical formula 3 in part or the whole of a luminescent layer having the compound represented by the chemical formula i as a host material. The compound represented by the chemical formula i efficiently emits blue color light and is chemically stable. The compound represented by the chemical formula 3 efficiently emits orange color light, and is chemically stable, and an excellent white color luminescent element is realized by these two materials.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic electroluminescent device (hereinafter, referred to as an organic EL device), in particular, an organic EL device having a blue light emitting function, and a white light emitting function using the blue light emitting function. Related to the element.

[0002]

2. Description of the Related Art Organic EL devices are advantageous for power saving.
It has a characteristic that it can emit light with a high viewing angle and high brightness, and is attracting attention as a next-generation flat display element and its flat light source.

[0003] In such an organic EL device, realizing white light emission requires not only a demand for multicolor and full color display panels, but also white light emission itself as display light or a backlight for a liquid crystal display or the like. There is also a need, and the ripple effect is great. However, in the prior art, there is a problem that blue light emission for realizing a white light emission function has low luminance and a short driving life.

In order to achieve white light emission, blue light emission with high efficiency and long life is first realized, 1) a method using light emission from three wavelengths of RGB, 2) blue + yellow to orange, or blue-green + red. In the case of the three-wavelength method of 1), a method of laminating light-emitting layers of RGB colors (1-a) and simultaneous doping of each of the RGB fluorescent dyes into the light-emitting layer are used. There is a method (1-b).

In the method (1-a), the blue EL is driven by driving.
There is a problem in that the intensity of the component decreases, the color shift due to the change in the white EL spectrum, and the luminous efficiency is low because the recombination zone extends over a plurality of layers.
In the method (1-b), the method is further divided into a high-molecular type and a low-molecular type. In the case of a polymer, a white color is obtained by mixing the fluorescent dyes of each color at the stage of adjusting the coating solution. However, it is difficult to control the mixing of the dyes, so that the luminous efficiency and the driving stability are far from practical use. In low-molecular-weight systems, it is possible to dope each color of fluorescent dye into the same light-emitting layer by vacuum deposition, but at the same time, controlling the deposition rate of many deposition sources to adjust the doping amount of each dye, It is very difficult considering actual production.

[0006] In the method of 2) using complementary colors of two wavelengths, 2
A method of laminating color light emitting layers (Japanese Patent No. 2991450, Japanese Patent Application Laid-Open No. 4-284395, Japanese Patent Application Laid-Open No. 6-158038)
Publication No. WO98 / 08360) and one light-emitting layer
Method for obtaining color light emission (Japanese Patent Application Laid-Open No. 9-208946,
JP-A-9-219289, JP-A-11-3297
No. 34).

In the method of laminating two light emitting layers,
Efficiency improvement effects, such as an increased opportunity for injection and recombination / emission of electrons and holes, can also be expected. Further, in the method of obtaining light emission of two colors with one light emitting layer, the structure is simplified, and
It is expected that color misregistration due to driving hardly occurs.

[0008]

However, in the case where two complementary colors are used, in the combination of blue-green and red, most of the red dyes that are currently proposed are used in the case where they are doped in the hole transport layer. Then, the fluorescence peak is shifted to the short wavelength side. Accordingly, there is a problem that red light emission cannot be obtained, and as a result, white color shift occurs. Further, as of today, a red pigment having durability comparable to that of a green pigment has not been developed. By using rubrene, which is known to emit stable light in yellow, an element having practical durability can be obtained. However, in this case, blue light emission with high purity is required to obtain white light emission. Therefore, it is essential to select a blue light emitting material having high luminance and long life.

It is an object of the present invention to realize blue light emission with high color purity and high efficiency and long life. Still another object is to provide an organic EL device capable of efficiently and stably obtaining high-purity white light by utilizing the above blue light emission.

[0010]

In order to achieve the above object, an organic EL device according to the present invention first forms a blue device having good characteristics, and uses the complementary color of blue light emission and yellow and orange light emission. Specifically, an organic EL device having an organic compound layer between a first electrode and a second electrode, wherein the organic compound layer has the following chemical formula (i):

Embedded image (However, R _{21 to} R ₂₆ in the formula are arbitrary substituents, and q _{21 to} q
₂₃ is an integer of 0 to 9), and has a light emitting layer containing an organic compound represented by the formula (1). The light emitting layer contains at least one or more fluorescent dyes in an amount of 0.1 mol% to 10 mol%.

The organic compound represented by the chemical formula (i) can obtain high-efficiency blue light emission even if the organic compound itself is used for the light emitting layer without doping the fluorescent dye. Therefore, higher brightness and longer life can be achieved.

Here, if a fluorescent dye having an emission wavelength peak of 480 nm or less and having an absorption in the fluorescent wavelength region of the chemical formula (i) is used as the fluorescent dye, the fluorescent dye from the chemical formula (i) can be more efficiently used. Energy can be transmitted, and highly efficient blue light emission can be realized. Furthermore, since the excitation energy is transferred to the fluorescent dye by doping with the fluorescent dye, the time required for the chemical formula (i) to be in the excited state is shortened, and the organic material of the chemical formula (i) is electrochemically degraded. It can be prevented and helps to extend the service life. Styrylbenzene derivatives as fluorescent dyes satisfying such conditions,
Coumarin derivatives, perylene derivatives, bisstyrylanthracene derivatives, styrylamine derivatives and the like are represented,
As a general formula, the following chemical formula (2)

Embedded image Can be used.

Changes in morphology and crystallization of the organic compound layer due to Joule heat due to current during driving are films (devices)
Although the lifetime is shortened, the effect of stabilizing the structure by the doped fluorescent dye also has an effect of alleviating the deterioration. An organic dye having such a high effect is required to have a high glass transition temperature and a high melting point, and a styrylbenzene derivative, a bisstyrylanthracene derivative, a styrylamine derivative and the like having a relatively large molecular weight are preferable.

The doping amount of these fluorescent dyes is 0.1 mol% or more of the host material in order to sufficiently transfer energy from the host, and 10 mol% or less in order to avoid concentration quenching due to association between the fluorescent dyes. Appropriate amount. By selecting the fluorescent dye material and the doping amount in consideration of such conditions, it is possible to further improve the characteristics of the chemical formula (i) in which good blue emission is obtained without doping the fluorescent dye.

[0015] An organic EL device according to another aspect of the present invention comprises:
White light emission is realized using the above-described blue light emission and light emission having a complementary color relationship with the blue light emission, and more specifically, an organic EL element having an organic compound layer between the first and second electrodes. The organic compound layer may be formed by the chemical formula (i) (wherein R _{21 to} R ₂₆ are any substituents, and q _{21 to} q ₂₃ are 0 to 9).
A first light-emitting layer containing an organic compound represented by the following chemical formula (3):

Embedded image Wherein at least two or more of R _{1 to} R _{7 in} the formula are substituents represented by the chemical formula (4) (where R _n and R ′ _n are arbitrary substituents, n is an integer of 1 or more, Q has, for example, a second light-emitting layer containing an organic compound composed of an aromatic group represented by a chemical formula (5) described below.

The organic compound represented by the chemical formula (i) can obtain highly efficient blue light emission even if the organic compound itself is used for the light emitting layer without doping a dye. In addition, this compound has a Tg of 160 ° C. or higher and is chemically stable.

The organic compound represented by the chemical formula (3) may be doped into Alq (quinolinol aluminum complex) which is widely used as a host of the electron transporting light emitting layer.
Even when doped into an aromatic tertiary amine used as a hole transporting layer, it emits orange light having a peak wavelength around 550 to 600 nm with high efficiency. In particular, as compared to the case of doping rubrene, which is known to exhibit stable yellow emission when doped in the hole transport layer, it has a peak wavelength on the longer wavelength side, and has the same high level. Shows durability (luminance half-life).

By using the organic compound represented by the chemical formula (i) and the organic compound represented by the chemical formula (3), white light having excellent color purity can be obtained by mixing blue light emission and orange light emission from the same device. An organic electroluminescent device that can emit light efficiently and has high durability can be realized.

Another embodiment of the present invention is an organic EL device including a plurality of organic compound layers between the first and second electrodes, wherein the organic compound layer comprises an organic compound represented by the above chemical formula (i). A light-emitting layer including the light-emitting layer, wherein the light-emitting layer is represented by the above-mentioned chemical formula (3) in at least a part of the region or the entire region in the layer, wherein at least two or more of R _{1 to} R _{7 in} the formula are represented by the chemical formula (4)
Contains an organic compound composed of a substituent represented by the formula:

In the above, the terminal group Q in the chemical formula (4) is represented by the following chemical formula (5)

Embedded image Can be adopted.

The organic compound represented by the chemical formula (i) and the organic compound represented by the chemical formula (3) emit light together when they are present in the same layer. Therefore, in the same light emitting layer, blue light caused by the organic compound of formula (i) and orange light caused by the organic compound of formula (3) can be obtained. Of the two types of organic compounds, the compound represented by the chemical formula (i) can be used as a host material, and the compound represented by the chemical formula (3) can be used as a guest material doped in the host material. .

In particular, the chemical formula (i)
And the organic compound represented by the chemical formula (3), blue and orange luminescence can be obtained in the entire light emitting layer. Therefore, the viewing angle dependence of chromaticity can be remarkably improved as compared with a stacked element in which the emission positions of two emission colors are different. Further, in the stacked type, the recombination region varies due to a change in the electric field applied when the luminance is changed, and therefore, the chromaticity may exhibit luminance dependency. However, if two different colors emit light in the entire light emitting layer, the light emitting positions of the two light emitting colors do not change relative to each other, so that the chromaticity does not exhibit luminance dependency.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention (hereinafter, referred to as embodiments) will be described below with reference to the drawings.

FIG. 1 shows a schematic sectional structure of an organic EL device which emits blue or white light according to the present invention. FIG.
In the above, an anode 12 using ITO (Indium Tin Oxide) or the like as a transparent electrode is formed on a transparent substrate 10 such as glass, and an organic compound layer 200 having a multilayer structure is formed thereon. The cathode 14 is formed thereon using, for example, LiF and Al as metal materials. Each layer is laminated in order from the substrate side, for example, by vacuum evaporation. The organic compound layer 200 includes at least the light-emitting layer 30, and has a single-layer structure of the light-emitting layer, a stacked structure of a hole-transport layer and a light-emitting layer, a stacked structure of a light-emitting layer and an electron-transport layer,
A stacked structure of a hole transporting layer, a light emitting layer, and an electron transporting layer can be employed. In the example of FIG. 1, the organic compound layer 200 has a hole injection layer 20, a hole transport layer 22, a light emitting layer 30, and an electron transport layer 28 laminated in this order from the anode 12 side.

[Embodiment 1] In the organic EL device according to Embodiment 1, the light-emitting layer 30 has the following chemical formula (i)

Embedded image (Wherein R _{21 to} R ₂₆ are arbitrary substituents, and q _{21 to} q ₂₃ are
(An integer from 0 to 9), and a blue fluorescent dye is doped as a guest material. This light emitting layer 30
On the other hand, when electrons are injected from the cathode 14 and holes are injected from the anode 12, the holes and electrons recombine in the compound (i) to generate excitons, and the energy is transferred to the fluorescent dye of the guest. Then, blue light emission due to the fluorescent material is obtained.

The fluorescent dye is represented by the following chemical formula (2)

Embedded image An organic compound represented by the following formula can be used.

The hole transporting layer is not particularly limited, but may have the following chemical formula (1)

Embedded image (However, in the formula, Ar _{31 to} Ar _{33 each} represent an arbitrary aryl group or an aromatic heterocyclic group.). Specifically, TPTE represented by the following chemical formula (8) and the like can be given.

[Embodiment 2] Organic EL according to Embodiment 2
The device has a two-layer structure in which the light emitting layer 30 includes a first light emitting layer and a second light emitting layer. The first light emitting layer (formed here on the electron transport layer 28 side) of the light emitting layer 30 has the above-mentioned chemical formula (i) (where R _{21 to} R ₂₆ are arbitrary substituents, q ₂₁
To q ₂₃ includes an organic compound shown in integer) of 0-9. The second light emitting layer (formed on the hole transport layer 22 side) has the following chemical formula (3)

Embedded image An organic compound represented by the formula (at least two of R _{1 to} R _{7 in} the formula:
The above includes the substituent represented by the chemical formula (4)).

With respect to the light emitting layer 30 having such a two-layer structure,
When electrons are injected from the cathode 14 and holes are injected from the anode 12, blue light emission due to the organic compound represented by the chemical formula (i) is obtained in the first light emitting layer (blue light emitting layer), and Orange light emission caused by the organic compound represented by (3) is obtained in the second light emitting layer (orange light emitting layer). Since the blue and orange colors obtained from both light emitting layers have a complementary color relationship, the two colors can be obtained from the corresponding first and second light emitting layers, so that the organic EL element according to the second embodiment achieves white light emission. Is done.

Third Embodiment Next, an organic EL device according to a third embodiment will be described. The difference from the second embodiment is the configuration of the light emitting layer 30. In the second embodiment, the light emitting layer has a two-layer structure of a blue light emitting layer (first light emitting layer) and an orange light emitting layer (second light emitting layer).
In the device, the light-emitting layer 30 contains the organic compound represented by the chemical formula (i) as a host material, and the light-emitting layer 30 partially covers the light-emitting layer (doped light-emitting layer) by the chemical formula (3).
Are contained as a guest material.

Here, to include in the partial region of the light emitting layer 30 means that the organic compound of the chemical formula (3) is contained particularly in a plane at a specific position in the laminating direction. For example, after the formation of the hole transport layer 22 in FIG. 1, the doping light emitting layer of the light emitting layer 30 is formed by simultaneously forming an organic compound of the chemical formula (i) as a host material and depositing an organic compound of the chemical formula (3) as a guest material. It can be obtained by evaporating a compound. After depositing the doped light emitting layer of a predetermined thickness on the hole transport layer 22, the deposition of the organic compound of the chemical formula (3) is stopped, and a single light emitting layer of the organic compound of the chemical formula (i) is continuously deposited.

With such a configuration, when electrons are injected into the light emitting layer 30 from the cathode 14 and holes are injected from the anode 12, blue light is obtained in the single light emitting layer in the light emitting layer 30,
In the doped light emitting layer, orange and blue light are obtained. For this reason, also in the organic EL element of the third embodiment, blue and orange lights having complementary colors are obtained, and white light emission can be realized. Compared with the second embodiment, the entire light emitting layer 30 has a smaller thickness, and two colors of light can be obtained therein, so that the single light emitting layer region and the doped light emitting layer region are formed very close to each other, The viewing angle dependency of the degree can be improved. In addition, when forming the light emitting layer 30, both the single light emitting layer and the doping light emitting layer use the organic compound of the chemical formula (i), and when forming the doping light emitting layer, the organic compound material of the chemical formula (3) is further deposited in a vapor deposition atmosphere. Should be added to

Fourth Embodiment In the third embodiment, the light emitting layer 30 includes the single light emitting layer region and the doping light emitting layer region. However, in the organic EL device according to the third embodiment, the entire light emitting layer 30 is provided. It includes the organic compound of the above formula (i) and the organic compound of the formula (3). Specifically, the chemical formula (i)
Is used as a host material, and an organic compound represented by chemical formula (3) as a guest material is dispersed in this material. Other configurations of the element are the same as those of the third embodiment. By employing such a single light emitting layer 30, a white light emitting element with high color purity can be realized and the light emitting layer 3
Since blue light emission and orange light emission occur uniformly in each region within 0, the viewing angle dependence of chromaticity can be made extremely small. Further, since the position of the recombination region does not change even when the applied electric field is changed, the positions of the blue and orange light emission in the light emitting layer 30 do not change, and the luminance dependency of the chromaticity can be extremely reduced. .

[Organic Compound of the Present Invention] Next, the organic compound represented by the chemical formula (i) and the organic compound represented by the chemical formula (3) used in the above embodiments will be described in detail.

(Organic compound represented by chemical formula (i)) This compound emits blue light as described above, and has a glass transition temperature Tg of 160 ° C. or higher and is chemically stable. R ₂₁ , R ₂₂ and R ₂₃ in the formula (i) are each a substituent. The substituents R ₂₁ , R ₂₂ , and R ₂₃ are preferably an alkyl group, an alkenyl group, an aryl group, a heteroaryl group, an alkoxy group, or the like, more preferably an alkyl group or an aryl group, and further preferably, An aryl group.

In the formula, q ₂₁ , q ₂₂ , and q ₂₃ are 0-9.
Represents an integer. q ₂₁ , q ₂₂ and q ₂₃ are preferably from 0 to 3
And more preferably 0 to 2, and still more preferably 0.1. When q ₂₁ , q ₂₂ , and q ₂₃ are 2 to 9, R
₂₁ , R ₂₂ and R ₂₃ may be the same or different from each other.

In the formula (i), R ₂₄ , R ₂₅ and R ₂₆ each represent a substituent, and examples of the substituent include those described above for R ₂₁ . R ₂₄ , R ₂₅ and R ₂₆ are preferably a hydrogen atom, an alkyl group or an aryl group, and more preferably a hydrogen atom or an alkyl group.

More specific examples of the substituents R _{21 to} R ₂₃ are as follows. Alkyl group (preferably having 1 to 30 carbon atoms, more preferably 1 to 20 carbon atoms, particularly preferably 1 to 10 carbon atoms, for example, methyl, ethyl,
iso-propyl, tert-butyl, n-octyl,
n-decyl, n-hexadecyl, cyclopropyl, cyclopentyl, cyclohexyl and the like. ), An alkenyl group (preferably having 2 to 30 carbon atoms, more preferably having 2 to 20 carbon atoms, particularly preferably having 2 to 10 carbon atoms, and examples thereof include vinyl, allyl, 2-butenyl, and 3-pentenyl. ), An alkynyl group (preferably having 2 to 30 carbon atoms, more preferably having 2 to 20 carbon atoms, particularly preferably having 2 to 10 carbon atoms, and examples thereof include propargyl and 3-pentynyl), and an aryl group (preferably). Is 6 to 30 carbon atoms, more preferably 6 carbon atoms
-20, particularly preferably 6-12 carbon atoms, for example, phenyl, p-methylphenyl, naphthyl, anthranyl and the like. ), An amino group (preferably having 0 to 30 carbon atoms, more preferably 0 to 20 carbon atoms, particularly preferably 0 to 10 carbon atoms, for example, amino, methylamino, dimethylamino, diethylamino, dibenzylamino, diphenylamino , Ditolylamino, etc.), an alkoxy group (preferably having 1 to 30 carbon atoms, more preferably 1 to 20 carbon atoms, and particularly preferably 1 carbon atom).
-10, for example, methoxy, ethoxy, butoxy,
2-ethylhexyloxy and the like. ), An aryloxy group (preferably having 6 to 30 carbon atoms, more preferably having 6 to 20 carbon atoms, particularly preferably having 6 to 12 carbon atoms, such as phenyloxy, 1-naphthyloxy, 2-
And naphthyloxy. ), A heteroaryloxy group (preferably having 1 to 30 carbon atoms, more preferably 1 to 20 carbon atoms, particularly preferably 1 to 12 carbon atoms, and examples thereof include pyridyloxy, pyrazyloxy, pyrimidyloxy, quinolyloxy, etc.) An acyl group (preferably having 1 to 30 carbon atoms, more preferably having 1 to 20 carbon atoms, particularly preferably having 1 to 12 carbon atoms, such as acetyl, benzoyl, formyl, and pivaloyl); and an alkoxycarbonyl group. (Preferably has 2 to 30 carbon atoms, more preferably 2 to 20 carbon atoms, particularly preferably 2 to 12 carbon atoms, such as methoxycarbonyl and ethoxycarbonyl.)
Aryloxycarbonyl group (preferably having 7 to 3 carbon atoms)
It has 0, more preferably 7 to 20 carbon atoms, particularly preferably 7 to 12 carbon atoms, such as phenyloxycarbonyl. ), An acyloxy group (preferably having 2 to 30 carbon atoms, more preferably having 2 to 20 carbon atoms, particularly preferably having 2 to 10 carbon atoms, such as acetoxy and benzoyloxy), and an acylamino group (preferably 2-30 carbon atoms, more preferably 2 carbon atoms
-20, particularly preferably 2-10 carbon atoms, such as acetylamino and benzoylamino. ), An alkoxycarbonylamino group (preferably having 2 to 30 carbon atoms, more preferably having 2 to 20 carbon atoms, particularly preferably having 2 to 12 carbon atoms, for example, methoxycarbonylamino and the like), aryloxycarbonylamino Group (preferably having 7 to 30 carbon atoms, more preferably having 7 to 20 carbon atoms, and particularly preferably having 7 to 12 carbon atoms.
And for example, phenyloxycarbonylamino and the like. ), A sulfonylamino group (preferably having 1 to 30 carbon atoms, more preferably having 1 to 20 carbon atoms, particularly preferably having 1 to 12 carbon atoms, for example, methanesulfonylamino, benzenesulfonylamino, etc.), and sulfamoyl. Groups (preferably having 0 to 3 carbon atoms)
It has 0, more preferably 0 to 20 carbon atoms, and particularly preferably 0 to 12 carbon atoms, and examples thereof include sulfamoyl, methylsulfamoyl, dimethylsulfamoyl, and phenylsulfamoyl. ), Carbamoyl group (preferably having 1 to 30 carbon atoms, more preferably having 1 to 2 carbon atoms)
0, particularly preferably 1 to 12 carbon atoms, for example, carbamoyl, methylcarbamoyl, diethylcarbamoyl, phenylcarbamoyl and the like. ), An alkylthio group (preferably having 1 to 30 carbon atoms, more preferably 1 to 20 carbon atoms, particularly preferably having 1 to 12 carbon atoms, such as methylthio and ethylthio, etc.), and an arylthio group (preferably carbon Numbers 6 to 30,
More preferably, it has 6 to 20 carbon atoms, particularly preferably 6 to 12 carbon atoms, such as phenylthio. ), A heteroarylthio group (preferably having 1 to carbon atoms)
30, more preferably 1 to 20 carbon atoms, particularly preferably 1 to 12 carbon atoms, such as pyridylthio, 2-benzimidolylthio, 2-benzoxazolylthio,
Benzthiazolylthio and the like. ), A sulfonyl group (preferably having 1 to 30 carbon atoms, more preferably having 1 to 20 carbon atoms, particularly preferably having 1 to 12 carbon atoms, and examples thereof include mesyl and tosyl). 1 to 30, more preferably 1 to 20 carbon atoms, particularly preferably 1 to 12 carbon atoms, for example, methanesulfinyl, benzenesulfinyl and the like; a ureido group (preferably 1 to 3 carbon atoms)
It has 0, more preferably 1 to 20 carbon atoms, and particularly preferably 1 to 12 carbon atoms, and examples thereof include ureido, methylureide, and phenylureide. ), A phosphoric amide group (preferably having 1 to 30 carbon atoms, more preferably 1 to 20 carbon atoms, particularly preferably 1 to 12 carbon atoms,
For example, diethylphosphoramide, phenylphosphoramide and the like can be mentioned. ), A hydroxy group, a mercapto group, a halogen atom (for example, a fluorine atom, a chlorine atom, a bromine atom,
Iodine atom), cyano group, sulfo group, carboxyl group,
Nitro group, hydroxamic acid group, sulfino group, hydrazino group, imino group, heterocyclic group (preferably having 1 to 3 carbon atoms)
0, more preferably 1 to 12 carbon atoms, and examples of the hetero atom include, for example, a nitrogen atom, an oxygen atom, a sulfur atom, specifically, for example, imidazolyl, pyridyl, quinolyl, furyl, thienyl, piperidyl, morpholino, benzoxazolyl , Benzimidazolyl, benzthiazolyl and the like. ), A silyl group (preferably having 3 to 4 carbon atoms)
It has 0, more preferably 3 to 30 carbon atoms, and particularly preferably 3 to 24 carbon atoms, and examples thereof include trimethylsilyl and triphenylsilyl. ).
These substituents may be further substituted. Examples of the organic compound represented by the chemical formula (i) described above include the following chemical formulas (ii) to (viii)

Embedded image

Embedded image

Embedded image

Embedded image

Embedded image

Embedded image

Embedded image And organic compounds such as those shown below.

(Organic compound represented by chemical formula (3))
Organic compound is a quinoline derivative compound and has the chemical formula
Substituent R in (3) ₁~ R₇Of at least two or more
N (n: an integer equal to or more than 1) two of the number represented by the chemical formula (4)
It has a structure substituted with a substituent having a heavy bond.

The terminal group Q in the chemical formula (4) is preferably an aromatic group (aromatic hydrocarbon or aromatic heterocyclic group). An example is the following chemical formula (5)

Embedded image A phenyl group as shown in the following can be adopted.

R _{1 to} R ₇ which are not substituted by the chemical formula (4)
Are independent of each other, and a hydrogen atom or any substituent other than a hydrogen atom can be adopted. For example, a hydrogen atom, a hydroxyl group, a mercapto group, a halogen atom,
Alkyl group, alkyl group, alkenyl group, alkynyl group, aryl group, heteroaryl group, alkoxy group, aryloxy group, heteroaryloxy group, alkylthio group, arylthio group, heteroarylthio group, amino group, cyano group, nitro group , Acyl group, ester group (alkoxycarbonyl group, aryloxycarbonyl group),
Carboxyl group (acyloxy group), acylamino group,
Alkoxycarbonylamino group, aryloxycarbonylamino group, sulfamoyl group, carbamoyl group, sulfo group, sulfonyl group, sulfinyl group, sulfino group, hydrazino group, imino group, ureido group, phosphoric amide group, hydroxamic acid group, silyl group, etc. Can be adopted. In the groups other than the substituent represented by the above formula (4), R ₁ and R ₂ , R ₂ and R ₃ , R ₃ and R ₄ , R ₄
And R ₅ , R ₅ and R ₆ , or R ₆ and R ₇ may be bonded to each other to form an aromatic ring or an aliphatic ring, or an aromatic ring or a heteroaromatic ring, Family ring,
The substituents that can be employed as the substituents for the aliphatic ring are the same as the characteristic groups listed above.

In the chemical formula (4), the substituents R _n and R ′ _n can be any characteristic groups and are independent of each other, for example, a hydrogen atom, a hydroxyl group, a mercapto group, a halogen atom,
Alkyl group, alkyl group, alkenyl group, alkynyl group, aryl group, heteroaryl group, alkoxy group, aryloxy group, heteroaryloxy group, alkylthio group, arylthio group, heteroarylthio group, amino group, cyano group, nitro group , Acyl group, ester group (alkoxycarbonyl group, aryloxycarbonyl group),
Carboxyl group (acyloxy group), acylamino group,
Alkoxycarbonylamino group, aryloxycarbonylamino group, sulfamoyl group, carbamoyl group, sulfo group, sulfonyl group, sulfinyl group, sulfino group, hydrazino group, imino group, ureido group, phosphoric amide group, hydroxamic acid group, silyl group, etc. Can be adopted. If the number of n of formula (4) is 2 or more, the double bond of the substituent R _n and R _'n is all the same, or all different, or may be any part identical.

The terminal group Q is preferably an aromatic group (aromatic hydrocarbon or aromatic heterocyclic group) represented by a phenyl group represented by the above chemical formula (5). Substituent R of terminal group Q
_Q (substituent R1 ₈ to R ₁₂₎ is not particularly limited, independent of each other, for example a hydrogen atom, a hydroxyl group, a mercapto group, a halogen atom, an alkyl group, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a hetero Aryl group,
Alkoxy group, aryloxy group, heteroaryloxy group, alkylthio group, arylthio group, heteroarylthio group, amino group, cyano group, nitro group, acyl group,
Ester group (alkoxycarbonyl group, aryloxycarbonyl group), carboxyl group (acyloxy group),
Acylamino group, alkoxycarbonylamino group, aryloxycarbonylamino group, sulfamoyl group, carbamoyl group, sulfo group, sulfonyl group, sulfinyl group, sulfino group, hydrazino group, imino group, ureido group, phosphoric amide group, hydroxamic acid group, A silyl group or the like can be employed. Adjacent substituents R _Q (for example, R ₈ and R ₉ , R ₉ and R ₁₀ , R ₁₀ and R ₁₁ , R ₁₁ and R ₁₂ ) are bonded to each other to form an aromatic ring or an aliphatic ring. The substituents which may be employed as the substituents of the aromatic ring, the heteroaromatic ring, the aliphatic ring, and the aliphatic ring may be any of the characteristic groups listed above as being applicable to R _{1 to} R _7. The same is true.

At least two of the substituents R _{1 to} R _{7 in} the chemical formula (3) are the substituents represented by the chemical formula (4).
The remaining substituents are not particularly limited, but it is preferable to introduce an electron-withdrawing substituent into at least one of them.

The substituent R _{Q in the} formula (5) is not particularly limited, but is preferably an electron donating substituent. Examples of the electron donating substituent include an amino group, an alkoxy group, an alkylthio group, an alkyl group, and an amino group substituted with an alkyl group.

As the organic compound represented by the chemical formula (3) described above, for example, the following chemical formula (6)

Embedded image And organic compounds such as those shown below.

The organic compound represented by the general formula (3), such as the chemical formula (6), can be used as a hole transport layer even if it is doped into Alq used as a host of the electron transport light emitting layer. Even when doped into an aromatic tertiary amine, it emits orange light having a peak wavelength around 550 nm to 600 nm with high efficiency. It also has a high melting point (221
° C) and is chemically stable.

[0048]

[Example 1] (Example 1-1: Blue light-emitting device in which an organic compound represented by the chemical formula (ii) is doped with a fluorescent dye represented by the following chemical formula (7)) An organic compound represented by the chemical formula (i) is formed in a light-emitting layer. The compound represented by the following chemical formula (ii)

Embedded image Using the organic compound shown in the above, as a guest fluorescent dye represented by the above general formula (2), the following chemical formula (7)

Embedded image An organic EL device having the cross-sectional structure shown in FIG.

First, vacuum deposition (7 × 10 ⁻⁵ P) was performed on a glass substrate on which a transparent electrode (anode) of ITO was previously formed.
According to a), a hole injection layer (CuPc: copper phthalocyanine) was deposited to a thickness of 15 nm, and then a hole transport layer was deposited to a thickness of 35 nm. As the hole transport layer, the compound represented by the general formula (1) may be represented by the following chemical formula (8)

Embedded image TPTE as shown in Table 1 was used as a material.

Next, a 20 nm light-emitting layer was deposited by co-evaporation with the compound of the formula (7) using the organic compound represented by the above chemical formula (ii) as a material of the blue light-emitting layer. (9)

Embedded image The organic compound represented by was vapor-deposited by 40 nm.

After this, LiF was deposited to a thickness of 0.5 nm and Al
Was deposited to a thickness of 150 nm to form a metal electrode (cathode) having a laminated structure, thereby producing an element portion. After the element part is formed, it is transported to a chamber that has been evacuated to a high vacuum, the inside of the chamber is purged with nitrogen, and the end of a metal sealing cap is adhered to the surface of the transparent electrode using epoxy resin and sealed. did.

When a direct current of 11 mA / cm ² was applied to the device, light emission of 863 cd / m ² was obtained. The emission color is X = 0.181 and Y = 0.33 in CIE chromaticity coordinates.
It was 8. The EL spectrum is shown in FIG. A peak near 470 nm is an emission peak from the organic compound represented by the chemical formula (7). Chromaticity coordinates of blue color of NTSC standard X = 0.
Although it has a large shift in the Y direction as compared with 14, Y = 0.08, it emits blue light.

(Example 1-2: Blue light-emitting device in which an organic compound represented by the chemical formula (ii) is doped with a fluorescent dye represented by the following chemical formula (10)) The light-emitting layer is represented by the chemical formula (ii) as an organic compound represented by the chemical formula (i) ) Is used as a guest fluorescent dye represented by the chemical formula (2).

Embedded image An organic EL device doped with 2.3% of the organic compound shown in (1) was prepared. FIG. 4 shows a cross-sectional structure of this element. Example 1
The difference from -1 is the fluorescent dye material to be doped.

When a direct current of 11 mA / cm ² was applied to the device, light emission of 669 cd / m ² was obtained. The emission color is X = 0.155 and Y = 0.2 in CIE chromaticity coordinates.
It was 13. The EL spectrum is shown in FIG. 475 nm
The near peak was the emission peak from the organic compound represented by the chemical formula (10), and emitted blue light with excellent color purity.

(Example 1-3: Blue light-emitting device in which an organic compound represented by the chemical formula (ii) is doped with perylene, a fluorescent dye represented by the chemical formula (11)) In the light-emitting layer, an organic compound represented by the chemical formula (i) is used. Using the organic compound shown in (ii) as a guest fluorescent dye, the following chemical formula (11)

Embedded image An organic EL device doped with 0.2% of the organic compound shown in (1) was prepared. FIG. 6 shows a cross-sectional structure of this device. Example 1
-1 is a fluorescent dye material to be doped and an electron transport layer material, and the following compound (12) of Alq (aluminoquinolinol complex) is used as an electron transport layer.

Embedded image The description is omitted because it is common except for using.

When a direct current of 11 mA / cm ² was applied to the device, light emission of 505 cd / m ² was obtained. Emission color is CIE
In the chromaticity coordinates, X = 0.155 and Y = 0.234. The EL spectrum is shown in FIG. 460nm and 490n
The peak near m is a characteristic emission peak from the organic compound represented by the chemical formula (11), and emitted blue light with excellent color purity.

[Comparative Example] (Comparative Example 1: Blue light-emitting device using organic compound of chemical formula (i)) As the organic compound represented by chemical formula (i) in the light-emitting layer, an organic compound represented by the following chemical formula (ii) And FIG.
An organic EL device having a sectional structure as shown in FIG. The difference from Examples 1-1 to 1-3 is that the chemical formula (i
i) The fluorescent layer is not contained as a doping material in the light emitting layer A of the organic compound represented by i), and the chemical formula (9) is used as the electron transporting material. .

When a direct current of 11 mA / cm ² was applied to the organic EL device manufactured as described above, 545 c
Light emission of d / m ² was obtained. The emission color was X = 0.179 and Y = 0.303 in CIE chromaticity coordinates. FIG.
Shows the EL spectrum of the device according to Comparative Example 1.
In FIG. 9, a peak near 475 nm is an emission peak from the organic compound represented by the above chemical formula (ii).
Chromaticity coordinate X = 0.14, Y of blue emission color of NTSC standard
Although it has a larger shift in the Y direction than 0.08, it emits blue light. However, since the half width of the EL peak is wide, it is necessary to take measures such as using a blue filter for use as a blue light emitting element.

The organic E of Examples 1-1 to 1-3 and Comparative Example 1
Table 1 shows emission luminance, luminous efficiency, and chromaticity coordinates of the L element when a DC current of 11 mA / cm ² was passed.

[0060]

[Table 1] High brightness is achieved by the effect of doping blue fluorescent dye. Further, since the driving voltage and the rise due to the doping of the fluorescent dye are small, the luminous efficiency in consideration of the voltage is 1.2 to 1.8 times in Examples 1-1 to 1-3 as compared with Comparative Example 1. Improved. This is because energy was efficiently transferred from the compound formula (ii) as the host material to the fluorescent dye.

Further, in Examples 1-1 to 1-3 and Comparative Example 1,
Initial luminance of element is 2400 cd / m ^TwoSo that the current
It was driven to perform a durability test. The results are shown in FIG.
You. The device of the example was compared with the non-doped device of comparative example 1.
In all cases, the time when the luminance is reduced by half (half life) is greatly increased
Improved. Also, 2400cd / m^TwoAnd high brightness which life measurement in
Is a fluorescent color
That doping with silicon increases stability at high temperatures.
I can judge.

[Example 2] (Example 2-1: Orange light emitting device using organic compound of chemical formula (3)) (2-1a) Use of organic compound of chemical formula (13) In Example 2-1a, As a light emitting material (here, a guest material), an organic compound represented by the general formula (3) is represented by the following chemical formula (13).

Embedded image The organic compounds shown in Table 1 were used. FIG. 11 shows Example 2-2.
4A shows a cross-sectional structure of the organic EL element according to FIG. The differences from the above Examples 1-1 to 1-3 are the thicknesses of the hole transport layer, the light emitting layer and the electron transport layer, and the materials of the light emitting layer and the electron transport layer. I do. The hole transport layer is formed by vapor deposition to a thickness of 35 nm using TPTE represented by the chemical formula (8) as a material, and the electron transport layer is formed by a quinolinol aluminum complex (Al) of the chemical formula (12).
q3) was used as a material, and was formed by vapor deposition on the following light emitting layer to a thickness of 60 nm. The light emitting layer uses TPTE, which is the same material as the hole transport layer, as a host material, and contains an organic compound represented by the above chemical formula (13) in the host material.
It is formed by doping 8%. That is, a region 10 nm from the interface of the hole transport layer with the electron transport layer is doped with 0.8% of the organic compound represented by the chemical formula (13), and the region having a thickness of 10 nm constitutes the light emitting layer B. I have.

When a direct current of 11 mA / cm ² was passed through the obtained organic EL device according to Example 2-1a, 6
Light emission of 00 cd / m ² was obtained. The emission color is an orange emission, and X = 0.468 and Y =
0.487. FIG. 12 shows the EL spectrum of this device. As can be seen from FIG. 12, orange light emission having a light emission peak near 580 nm is obtained.

(2-1b) Use of Organic Compound of Chemical Formula (14) In Example 2-1b, an organic compound represented by the above general formula (3) was used as a light emitting material (here, guest material) of the light emitting layer. As the following chemical formula (14)

Embedded image The organic compounds shown in Table 1 were used. Similarly to Example 2-1a, the chemical formula (14) was applied to TPTE as a host material in a region of 10 nm from the interface of the hole transport layer with the electron transport layer.
The light emitting layer B was formed by doping 1.0% of the organic compound of the above. The organic EL device according to Example 2-1b was implemented except that the organic compound represented by the chemical formula (14) was doped as the light emitting material instead of the organic compound represented by the chemical formula (13). It has the same configuration as the organic EL device of Example 2-1a (see FIG. 11 for the cross-sectional structure).

In the organic EL device according to Example 2-1b, 11
When a direct current of mA / cm ² was applied, 676 cd /
An emission of m ² was obtained. The emission color is yellow-orange, and C
X = 0.433, Y = 0.516 in IE chromaticity coordinates
Met. FIG. 13 shows the EL spectrum of this device, and an emission peak is obtained at around 560 nm.

FIG. 14 shows the chromaticity coordinates of the luminescent colors obtained by the organic EL device of Comparative Example 1 and the organic EL devices of Examples 2-1a and 2-1b. The light emission (blue light emission) caused by the organic compound represented by the chemical formula (ii) as in Comparative Example 1 and the chemical formula (1) as in Example 2-1a
When two complementary colors are used for the light emission due to 3) or the light emission due to the organic compound represented by the chemical formula (14) as in Example 2-1b, the light emission obtained from the combination thereof is shown in FIG. The chromaticity coordinates of the luminescent color of the device of Comparative Example 1 and the chromaticity coordinates of the luminescent color of the device of Example 2-1a or 1b are considered to indicate any chromaticity on a straight line. .

Here, the area surrounded by the curve described in the central area of FIG. 14 is an "area showing approximately white" in the CIE chromaticity coordinates. When the organic compound represented by the chemical formula (ii) is used as the blue light-emitting material for the blue light-emitting layer, and another dye that emits blue light is not doped into this material, the organic compound represented by the chemical formula (13) is used as an orange light-emitting material. It can be seen that the use of the compound (Example 2-1a) has more portions overlapping the white region shown in FIG. 14 than Example 2-1b. Therefore, as the orange light emitting material as in Example 2-1a, the organic compound represented by the chemical formula (13) can easily emit light near white light more easily than the organic compound represented by the chemical formula (14). I understand.

Note that the “region showing approximately white” shown in FIG. 14 corresponds to the yellowish white shown in FIG. 1 “General chromaticity classification of system color names” described in JIS Z 8110. , Greenish white, bluish white and purple white.

Further, as the blue light emitting layer, the chemical formula (ii)
Example 1-1, using the organic compound of
As shown in 1-2 or 1-3, when another dye that emits blue light is doped as a guest, it is possible to further improve the color purity of blue (NTSC).
Approaching standard). In such a case, white light emission can be obtained even when the organic compound represented by the chemical formula (14) is used as the orange light emitting material.

Example 2-2: White Emission Using Organic Compound of Chemical Formula (ii) and Organic Compound of Chemical Formula (13) FIG. 15 shows a cross-sectional structure of an organic EL device according to Example 2-2. Is shown. In the present Example 2-2, the same organic compound of the chemical formula (ii) as that in Comparative Example 1 was used for the blue light emitting layer (light emitting layer A). Orange light emitting layer (light emitting layer B)
Has the same material as the hole transport layer (TPTE).
Example E as a host material and E as a guest material
The organic compound represented by the chemical formula (13) used in 1a was employed.
The light-emitting layer B contains an organic compound of the chemical formula (13) in an area of 5 nm from the interface of the hole transport layer with the blue light-emitting layer A.
% Doped. In the electron transport layer, Comparative Example 1 was used.
Similarly to the above, the organic compound represented by the chemical formula (9) was used.

[0071]

[Table 2] The above Table 2, the organic EL element 0.11mA / cm ² according to the obtained Example 2-2, 1.1 mA / cm ^2, 11m
Luminance and emission color C when a DC current of A / cm ² is applied
The IE chromaticity coordinates are shown. FIG. 16 shows CIE chromaticity coordinates of the element according to Example 2-2. From FIG. 16, the chromaticity coordinates of the obtained luminescent color are the chromaticity coordinates of the blue light emission of the element obtained in Comparative Example 1 and the orange color of the element obtained in Example 2-1a under any current conditions. It can be seen that it is located on a straight line connecting the chromaticity coordinates of the light emission. In the present embodiment 2-2, the blue component is strong when the current is small and the luminance is low, and the orange component is increased as the current is increased and the luminance is increased. It is in the area showing white. It is considered that such a luminance dependency of chromaticity is caused by a change in a light emitting region by changing a current (voltage) supplied between the anode and the cathode. From the above, it can be seen that although the luminance dependence of chromaticity is slightly large, good white light emission can be obtained with high efficiency by combining the materials used in Example 2-2. Further, it is considered that the luminance dependency of chromaticity can be reduced by optimizing the thickness and the doping amount of the light emitting layer B, that is, the layer doped with the organic compound of the chemical formula (13) used as the guest material. Can be

[Comparative Example] (Comparative Example 2-1: Fabrication of a device in which rubrene is doped in a hole transport layer and emission characteristics of the device) As Comparative Example 2-1, the hole transport layer was compared with the electron transport layer. An organic EL device in which rubrene was doped at 4.7% in a region 5 nm from the interface was produced. This device has the same structure as the devices shown in Examples 2-1a and 1b and differs only in the compound doped in the light emitting layer B.

When a direct current of 11 mA / cm ² was applied to the obtained device, light emission of 965 cd / m ² was obtained. The emission color was yellow-orange, with X = 0.451 and Y = 0.528 in CIE chromaticity coordinates.

FIG. 17 plots the chromaticity coordinates of the emission color of the organic EL element according to Comparative Example 2-1 and the chromaticity coordinates of blue of the element according to Comparative Example 1. White is obtained using two complementary colors of light emission (orange light) caused by rubrene used as a light emitting material in Comparative Example 2-1 and light emission (blue light) from an organic compound represented by the chemical formula (ii). In this case, it is considered that the luminescent chromaticity of the white light emitting device using these two materials exists at any position on the straight line connecting the chromaticity coordinates of the two devices shown near the center of FIG. Can be

As can be seen from FIG. 17, the straight line connecting these two points hardly intersects with the “region showing approximately white”. Therefore, good white color cannot be expected from the combination of the rubrene used in Comparative Example 2-1 and the organic compound of the chemical formula (ii) used in Comparative Example 1.

(Comparative Example 2-2: Fabrication of Device Using Organic Compound of Chemical Formula (ii) and Rubrene and Light Emission Characteristics of Device) Next, in Comparative Example 2-2, a blue light emitting layer (light emitting layer A)
A layer using the organic compound of the above chemical formula (ii),
An organic EL device in which the orange light emitting layer (light emitting layer B) was formed by doping 5.0% of rubrene in a region of 5 nm from the interface of the hole transport layer with the blue light emitting layer was manufactured. The device structure was the same as that of Example 2 shown in FIG. 15 except that the light emitting layer B was doped with rubrene instead of the organic compound of the chemical formula (13).
This is the same as the element structure according to -2.

[0077]

[Table 3]Table 3 shows that the obtained organic EL device according to Comparative Example 2-2 was obtained.
0.11mA / cm ^Two, 1.1 mA / cm^Two, 11mA
/ Cm^TwoOf luminance and emission color when DC current is applied
E shows the chromaticity coordinates. Also, FIG.
Organic EL device of Comparative Example 2-2 when DC current was changed
The child CIE chromaticity coordinates are plotted. Comparative Example 2-1
As described in, the chromaticity of the emission color obtained in Comparative Example 2-2
The coordinates are on a straight line connecting the two points shown in FIG. So
The device of Comparative Example 2-2 has a color similar to that of Example 2-2.
There is a luminance dependence of the degree (see FIG. 16). Blue-white at low brightness
Color, and yellowish-white at high luminance.
The difference is that the luminance may be changed in Comparative Example 2-2.
That is, good white light emission cannot be obtained.

[0078]

[Table 4] Table 4 shows the devices of Example 2-2 and Comparative Example 2-
0.11 mA / cm ² to 11 mA
/ Cm ² CI changes in emission color at the time of changing the current to
It is represented by the amount of change in coordinates in the E chromaticity coordinates. From Table 4, it can be seen that the change in chromaticity due to luminance (current) is large in each element, but the change in the element of Example 2-2 is smaller than that in Comparative Example 2-2.

Example 3 As Example 3, a white light-emitting organic EL device in which a part of a light-emitting layer containing an organic compound represented by the general formula (i) was doped with an organic compound represented by the chemical formula (13) Was prepared. FIG. 19 shows the configuration of the organic EL element according to the third embodiment. As shown
The blue light-emitting layer (light-emitting layer A) is formed by vapor deposition of an organic compound represented by the chemical formula (ii). In a region 5 nm from the interface between the blue light-emitting layer and the hole transport layer, a light-emitting layer C is formed. An element doped with 1.0% of the organic compound represented by (13) was produced. An organic compound represented by the chemical formula (9) was used for the electron transport layer in the same manner as in Example 2-2. The device configuration is the same as the device of Example 2-2 except for the configuration of the light emitting layer.

[0080]

[Table 5] Table 5, 0.11mA / cm ² to the organic EL element according to the obtained Example ^{3, 1.1mA / cm 2, 11mA} /
CIE of luminance and emission color when a DC current of cm ² is applied
Indicates chromaticity coordinates. FIG. 20 shows CIE chromaticity coordinates. In the case of the organic EL device according to Example 3, the chromaticity coordinates of the emission color obtained under each current condition are the chromaticity coordinates of the device of Comparative Example 1 (blue) and the color of the device of Example 2-1a (orange). It is not on the straight line connecting the degree coordinates. This is the third embodiment.
In the device according to the above, the blue light emitting layer is doped with the organic compound of the chemical formula (13) instead of the hole transport layer, and the organic compound of the chemical formula (1)
This is considered to be because the emission spectrum of the organic compound of 3) has a dependency on the host material.

The device according to Example 3 exhibited a blue color at low luminance, as can be seen from FIG. 20, but several tens cd / m ^2.
At the above luminance, white bluish light emission was exhibited. Adjusting the doping amount of the organic compound of the chemical formula (13), or
The emission color can be optimized by changing the thickness of the doped layer.

Example 4 As Example 4, a white light-emitting organic EL device in which the organic compound represented by the chemical formula (3) was doped over the entire area of the light-emitting layer containing the organic compound represented by the general formula (i). Produced. FIG. 21 shows the configuration of the element according to the fourth embodiment. Example 3 shown in FIG.
The elements are the same except for the structure of the light emitting layer. In Example 4, the light-emitting layer D was a single layer, and the light-emitting layer D used an organic compound represented by the chemical formula (ii) as a host material, and used an organic compound represented by the chemical formula (13). It is used as a guest material and is doped with 0.2% in the host. In the light emitting layer D, the doping (dispersion) ratio of the guest material is constant.

[0083]

[Table 6] Table 6 shows that the organic EL device according to Example 4 has a thickness of 0.11 m.
A / cm ^2, indicating the luminance and luminescent color of the CIE chromaticity coordinates upon applying a direct current of ^{1.1mA / cm 2, 11mA / cm} 2. FIG. 22 shows the CI of the device according to the fourth embodiment.
E shows the chromaticity coordinates. Also in the device according to Example 4, the organic compound represented by the chemical formula (13) was replaced with the organic compound represented by the chemical formula (i).
Since the organic compound represented by i) is doped, the chromaticity coordinates of the emission color do not fall on the straight line in the figure as shown in FIG. In other words, it is closer to the desired high-purity white. Further, as shown in Table 6 and FIG. 22, it can be seen that even when the current conditions are changed, the change in chromaticity is very small, and the luminance dependence of chromaticity is extremely small. As described above, the device of Example 4 has a small change in chromaticity and can exhibit extremely good white even as white.

The organic EL device according to the fourth embodiment is
After driving until the luminance was reduced by half at an initial luminance of 2400 cd / m ² by C low-current driving, a current of 11 mA / cm ² was passed to measure the chromaticity coordinates of the emission color. FIG. 23 shows chromaticity coordinates before and after the luminance halving. FIG. 23 also shows the result of the same measurement performed on the device of Example 2-2 for comparison. From this figure, it can be seen that in the case of the fourth embodiment, the chromaticity shift after the luminance is reduced by half is also very small.

From the above, the method of doping the organic compound represented by the chemical formula (13) into all the blue light emitting layers of Example 4 can minimize the luminance dependence and the driving time dependence of chromaticity. It can be seen that this is the most preferable method of the present invention.

[0086]

As described above, according to the present invention, a fluorescent dye is added to the compound represented by the chemical formula (i).
A high-efficiency long-life blue organic EL device can be realized by containing from 10 mol% to 10 mol%. Also, the chemical formula (i)
By using the compound represented by the formula and the compound represented by the chemical formula (3) in combination, blue light emission and orange light emission can be simultaneously obtained in the same light emitting surface, and white light emission with excellent color purity can be achieved. In addition, a white light emitting element having high efficiency and high durability can be realized.

[Brief description of the drawings]

FIG. 1 is a view showing a schematic sectional configuration of an organic EL device according to the present invention.

FIG. 2 is a diagram illustrating a cross-sectional configuration of a blue light emitting device according to Example 1-1.

FIG. 3 is a diagram showing an EL spectrum of a blue light emitting device according to Example 1-1.

FIG. 4 is a diagram illustrating a cross-sectional configuration of a blue light emitting device according to Example 1-2.

FIG. 5 is a diagram showing an EL spectrum of a blue light emitting device according to Example 1-2.

FIG. 6 is a diagram showing a cross-sectional configuration of a blue light emitting device according to Example 1-3.

FIG. 7 is a diagram showing an EL spectrum of a blue light emitting device according to Example 1-3.

FIG. 8 is a diagram illustrating a cross-sectional configuration of a blue light emitting element according to Comparative Example 1.

FIG. 9 is a diagram showing an EL spectrum of a blue light emitting device according to Comparative Example 1.

FIG. 10 is a diagram showing the operating life of the blue light emitting devices according to Examples 1-1, 1-2 and 1-3 and Comparative Example 1.

FIG. 11 is a diagram showing a cross-sectional structure of an orange light emitting device according to Example 2-1a.

FIG. 12 shows EL of an orange light emitting device according to Example 2-1a.
It is a figure showing a spectrum.

FIG. 13 shows an EL of an orange light emitting device according to Example 2-1b.
It is a figure showing a spectrum.

FIG. 14 shows CIE chromaticity coordinates of the emission color of each element of Comparative Example 1 and Examples 2-1a and 2-1b.

FIG. 15 is a diagram showing a cross-sectional structure of a white light emitting device according to Example 2-2.

FIG. 16 shows CIE chromaticity coordinates of white light of the device of Example 2-2.

FIG. 17 shows CIE chromaticity coordinates of the emission color of each element of Comparative Example 1 and Comparative Example 2-1.

FIG. 18 shows CIE chromaticity coordinates of the emission color of the device of Comparative Example 2-2.

FIG. 19 is a diagram showing a cross-sectional structure of a white light emitting device of Example 3.

FIG. 20 is CIE chromaticity coordinates of the emission color of the device of Example 3.

FIG. 21 is a view showing a cross-sectional structure of a white light emitting device of Example 4.

FIG. 22 shows CIE chromaticity coordinates of the emission color of the device of Example 4.

FIG. 23 shows CIE chromaticity coordinates before and after reducing the luminance of each element of Example 4 and Example 2-2.

[Explanation of symbols]

Reference Signs List 10 substrate, 12 anode (transparent electrode), 14 cathode (metal electrode), 20 hole injection layer, 22 hole transport layer, 28
Electron transport layer, 30 light emitting layer, 200 organic compound layer.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H05B 33/22 H05B 33/22 D (72) Inventor Koji Noda Koji 41 No. 1 Inside Toyota Central Research Laboratories Co., Ltd. (72) Inventor Tomohiko Mori 41-cho, Yokomichi, Oji, Nagakute-machi, Aichi-gun, Aichi Prefecture (1) Toyoda Central Research Institute, Inc. (72) Inventor Hisato Takeuchi Hisashi Takeuchi 41, Odaicho Chuchu-Yokomichi, Nagakute-cho, Aichi-gun, Aichi Makoto Mohri 41, Chukku Yokomichi, Nagakute-cho, Aichi-gun, Aichi, Japan 1 Toyota Central R & D Laboratories Co., Ltd. (72) Inventor Tatsuya Igarashi Minami Kanagawa Hilt City Nakanuma 210 address Fuji Photo Film Co., Ltd. in the (72) inventor Hisashi Okada Kanagawa Prefecture Minamiashigara Nakanuma 210 address Fuji Photo Film Co., Ltd. in the F-term (reference) 3K007 AB02 AB03 AB04 AB11 BB01 CA01 CB01 DA01 DB03 EB00

Claims (7)

[Claims] An organic electroluminescent device comprising an organic compound layer between first and second electrodes, wherein the organic compound layer has the following chemical formula (i): (Where R _{21 to} R ₂₆ in the formula are arbitrary substituents, and q _{21 to} q
₂₃ is an integer of 0 to 9), and contains at least a light emitting layer containing an organic compound represented by the formula (1). Characteristic organic electroluminescent device. 2. The organic electroluminescent device according to claim 1, wherein the organic compound layer has a hole transport layer, and the hole transport layer has the following chemical formula (1). (Wherein, Ar _{31 to} Ar ₃₃ in the formula represent an arbitrary aryl group or an aromatic heterocyclic group). An organic electroluminescent device comprising an organic compound represented by the formula: 3. The organic electroluminescent device according to claim 1, wherein the fluorescent dye is represented by the following chemical formula (2). (However, R _{41 to} R ₄₄ in the formula represent an arbitrary substituent, and Ar
₄₁ represents an arbitrary aryl group or an aromatic heterocyclic group. An organic electroluminescent device represented by the formula: 4. An organic electroluminescent device comprising an organic compound layer between first and second electrodes, wherein said organic compound layer has the following chemical formula (i): (Where R _{21 to} R ₂₆ in the formula are arbitrary substituents, and q _{21 to} q
₂₃ is an integer of 0 to 9).
A light-emitting layer, and the following chemical formula (3): Wherein at least two or more of R _{1 to} R _{7 in} the formula are substituents represented by the chemical formula (4) (where R _n and R ′ _n are arbitrary substituents, n is an integer of 1 or more, Q is a second light-emitting layer containing an organic compound composed of an aromatic group). 5. An organic electroluminescent device comprising at least one organic compound layer between first and second electrodes, wherein the organic compound layer has the following chemical formula (i): (Where R _{21 to} R ₂₆ in the formula are arbitrary substituents, and q _{21 to} q
₂₃ is an integer of 0 to 9), and has a light-emitting layer containing an organic compound represented by the following chemical formula (3) in at least a part of the light-emitting layer. Wherein at least two or more of R _{1 to} R _{7 in} the formula are substituents represented by the chemical formula (4) (where R _n and R ′ _n are arbitrary substituents, n is an integer of 1 or more, Q is an organic electroluminescent device comprising an organic compound composed of an aromatic group). 6. The organic electroluminescent device according to claim 4, wherein Q in the chemical formula (4) is the following chemical formula (5). (Wherein R _{8 to} R ₁₂ in the formula are arbitrary substituents). 7. The organic electroluminescent device according to claim 4, wherein n in the chemical formula (4) is:
An organic electroluminescent device comprising at least two.