JP2009076817A - Organic electroluminescent element, and display unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic electroluminescent element capable of improving light emission efficiency and excellent in life characteristics thereby. <P>SOLUTION: A blue electroluminescent element is configured to pinch an organic layer where at least an hole transporting layer and a light-emitting layer are laminated in this order from an anode between the anode and a cathode, wherein the light-emitting layer contains a host material and a blue light emitting dye, and the hole transporting layer is provided adjacent to the light-emitting layer and contains a compound represented by formula (1) or formula (2) and the blue light emitting dye. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an organic electroluminescent element and a display device, and more particularly, to a blue light emitting organic electroluminescent element and a display device using the same.

  In recent years, a display device using an organic electroluminescent element (so-called organic EL element) has attracted attention as a lightweight and highly efficient flat panel display device.

  An organic electroluminescent element constituting such a display device is provided on a transparent substrate made of glass or the like, for example, an anode made of ITO (Indium Tin Oxide: transparent electrode) in order from the substrate side, an organic layer, and A cathode is laminated. The organic layer has a structure in which a hole injecting layer, a hole transporting layer, and an electron transporting light emitting layer are sequentially stacked in this order from the anode side. In the organic electroluminescence device configured as described above, electrons injected from the cathode and holes injected from the anode are recombined in the light emitting layer, and light generated during the recombination is transmitted through the anode to the substrate side. Is taken out of.

  As an organic electroluminescent element, in addition to the above-described structure, a structure in which a cathode, an organic layer, and an anode are sequentially laminated in order from the substrate side, and an electrode positioned on the upper side (upper electrode as a cathode or an anode) There is also a so-called top-emitting type in which light is extracted from the upper electrode side opposite to the substrate by forming a transparent material. In particular, in an active matrix display device in which a thin film transistor (TFT) is provided on a substrate, a so-called Top Emission structure in which a top emission type organic electroluminescence element is provided on a substrate on which a TFT is formed. This is advantageous in improving the aperture ratio of the light emitting portion.

  In consideration of the practical application of the display device using the organic electroluminescent element, in addition to widening the opening of the organic electroluminescent element to increase the light extraction efficiency, there is a need to improve the luminous efficiency of the organic electroluminescent element. is there. In view of this, various materials and layer configurations for improving luminous efficiency have been studied.

  For example, in the case of a blue light-emitting element, it is disclosed that a perylene derivative or a chrysene derivative exhibits good blue light emission in addition to a conventionally known distyrylarene compound (for example, see Patent Documents 1 to 3 below). ).

  In addition, it is effective to increase the efficiency of the light emitting layer by energy transfer between two compounds composed of a host and a dopant. As a host material, for example, dinaphthylanthracene (ADN) having an anthracene skeleton has been proposed (see Non-Patent Document 1 below).

  Further, various molecular designs have been made for the hole transport layer, and one of them is disclosed that a starburst type amine compound is useful for an organic electroluminescence device (Patent Documents 4 to 8 below). reference).

WO02 / 02059 gazette JP 2000-182776 A JP 2006-256969 A Japanese Patent Laid-Open No. 2006-22052 JP 2001-335543 A JP-A-10-284252 Japanese Patent Laid-Open No. 7-53955 JP-A-4-308688 APPLIED PHYSICS LETTERS, 80, 3201-3203, 2002

  By the way, when performing full color display in a display device using an organic electroluminescent element, a configuration in which a white light emitting organic electroluminescent element and a color filter of each color are combined, or each color that emits light in three primary colors (red, green, and blue) is used. The structure which arranged the organic electroluminescent element is mentioned. Among these, in the configuration of white light emission + color filter, light loss due to the color filter occurs. For this reason, from the viewpoint of emission light extraction efficiency, a configuration in which organic electroluminescent elements of respective colors are arranged is advantageous.

  However, even in a configuration in which organic electroluminescent elements of each color are arranged, the light emitting efficiency of the organic electroluminescent element using the above-mentioned ADN as the host material of the light emitting layer is very low, which is necessary and sufficient for the configuration of the display device. It was difficult to obtain brightness. In particular, in an organic electroluminescent device, a current load increases in order to obtain luminance, so that there is a problem that luminance degradation is more severe as the device has lower luminous efficiency.

  Accordingly, the present invention provides an organic electroluminescent device that can improve luminous efficiency and thereby have a good lifetime characteristic. Furthermore, by using this organic electroluminescent device, the display characteristic is good and power consumption is reduced. It is an object to provide a display device that can be kept low.

  In order to achieve such an object, the present invention provides a blue luminescent material in which an organic layer in which at least a hole transport layer and a light emitting layer are laminated in this order from the anode side is sandwiched between the anode and the cathode. In the organic electroluminescent element, the light emitting layer contains a host material and a blue light emitting dye. In particular, the hole transport layer is provided adjacent to the light emitting layer, and includes a compound represented by the following general formula (1) or general formula (2) and a blue light emitting dye.

Ar ¹ and Ar ² in the general formula (1) each independently represent an aromatic hydrocarbon ring group or an aromatic heterocyclic group. R ^{1 to} R ⁸ are each independently a hydrogen atom, halogen atom, alkyl group, aralkyl group, alkenyl group, cyano group, amino group, acyl group, alkoxycarbonyl group, carboxyl group, alkoxy group, aryloxy group. , An alkylsulfonyl group, a hydroxyl group, an amide group, an aromatic hydrocarbon ring group, or an aromatic heterocyclic group, and adjacent ones of R ^{1 to} R ⁸ may form a ring. X represents a linking group formed by bonding 1 to 4 divalent aromatic groups.

X ¹ in the general formula (2) represents an N-carbazoyl group, an N-phenoxadiyl group, or an N-phenothiadiyl group. X ² represents an N-carbazoyl group, an N-phenoxadiyl group, an N-phenothiadiyl group, or —NAR ³ AR ⁴ (AR ³ and AR ⁴ are heterocyclic aromatic groups). B ¹ and B ² each independently represent a hydrogen atom, an alkyl group, a carbocyclic aromatic group, a heterocyclic aromatic group, or an aralkyl group. Z ¹ and Z ² each independently represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a carbocyclic aromatic group, or a heterocyclic aromatic group.

  The above hole transport layer may be composed of a plurality of layers. In this case, the hole transport layer in contact with the light emitting layer is composed of the compound represented by the general formula (1) or the general formula (2) described above. And a blue light emitting dye. Further, the blue light emitting dye in the hole transport layer may be the same as the blue light emitting dye in the light emitting layer.

  The present invention is also a display device in which the organic electroluminescent element as described above is provided as a blue light emitting element in a part of a plurality of pixels.

  In the organic electroluminescent element having the above-described configuration, as will be described in detail in the following examples, the hole transport layer exhibits high current efficiency as compared with the case where the blue light-emitting dye is not included, and the current load is further increased. As a result, it has been found that a long life can be obtained.

  As a result, according to the present invention, it is possible to obtain a blue light-emitting organic electroluminescent device with good luminous efficiency, thereby reducing the current load for ensuring luminance in organic electroluminescence viewing and reducing the lifetime. It becomes possible to improve the characteristics. In addition, it is possible to improve display characteristics and reduce power consumption in a display device using such an organic electroluminescent element as a blue light emitting element.

  Hereinafter, embodiments of the present invention will be described in detail in the order of an organic electroluminescent element and a display device using the same based on the drawings.

≪Organic electroluminescent element≫
FIG. 1 is a cross-sectional view schematically showing an organic electroluminescent element of the present invention. The organic electroluminescent element 11 shown in this figure is formed by laminating an anode 13, an organic layer 14, and a cathode 15 in this order on a substrate 12. Among these, the organic layer 14 is formed by laminating, for example, a hole injection layer 14a, a hole transport layer 14b, a light emitting layer 14c, and an electron transport layer 14d in this order from the anode 13 side.

  The present invention is characterized in that the hole transport layer 14b is composed of a single layer or a plurality of layers, and the hole transport layer 14b adjacent to the light emitting layer 14 contains the above-described compound and a blue light emitting dye. In the following, it is assumed that the organic electroluminescent element 11 is configured as a top-emitting element that extracts light from the side opposite to the substrate 12, and details of each layer in this case will be described in order from the substrate 12 side.

<Substrate 12>
The substrate 12 is a support on which the organic electroluminescent elements 11 are arranged and formed on one main surface side, and may be a known substrate, for example, a film or sheet made of quartz, glass, metal foil, or resin. Of these, quartz and glass are preferable. In the case of resin, methacrylic resin represented by polymethyl methacrylate (PMMA), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), poly Examples thereof include polyesters such as butylene naphthalate (PBN), polycarbonate resins, and the like, but it is necessary to perform a laminated structure and surface treatment that suppress water permeability and gas permeability.

<Anode 13>
The anode 13 has a large work function from the vacuum level of the electrode material in order to inject holes efficiently, for example, aluminum (Al), chromium (Cr), molybdenum (Mo), tungsten (W), copper (Cu), silver (Ag), gold (Au) metals and alloys thereof, oxides of these metals and alloys, or alloys of tin oxide (SnO ₂ ) and antimony (Sb), ITO (indium) Tin oxide), InZnO (indium zinc oxide), alloys of zinc oxide (ZnO) and aluminum (Al), and oxides of these metals and alloys are used alone or in a mixed state.

  Further, the anode 13 may have a laminated structure of a first layer having excellent light reflectivity and a second layer having a light transmittance and a high work function provided thereon.

  The first layer is made of an alloy containing aluminum as a main component. The subcomponent may include at least one element having a work function relatively smaller than that of aluminum as a main component. As such an auxiliary component, a lanthanoid series element is preferable. Although the work function of the lanthanoid series elements is not large, the inclusion of these elements improves the stability of the anode and also satisfies the hole injection property of the anode. In addition to lanthanoid series elements, elements such as silicon (Si) and copper (Cu) may be included as subcomponents.

  The content of subcomponents in the aluminum alloy layer constituting the first layer is preferably about 10 wt% or less in total for Nd, Ni, Ti, or the like that stabilizes aluminum. Thereby, while maintaining the reflectance in the aluminum alloy layer, the aluminum alloy layer can be stably maintained in the manufacturing process of the organic electroluminescent element, and further, processing accuracy and chemical stability can be obtained. In addition, the conductivity of the anode 13 and the adhesion to the substrate 12 can be improved.

  Examples of the second layer include a layer made of at least one of an oxide of an aluminum alloy, an oxide of molybdenum, an oxide of zirconium, an oxide of chromium, and an oxide of tantalum. Here, for example, when the second layer is an oxide layer of an aluminum alloy containing a lanthanoid element as a subcomponent (including a natural oxide film), the oxide of the lanthanoid element has a high transmittance, so that this is included. The transmittance of the second layer is improved. For this reason, it is possible to maintain a high reflectance on the surface of the first layer. Further, the second layer may be a transparent conductive layer such as ITO (Indium Tin Oxide) or IZO (Indium Zinc Oxide). These conductive layers can improve the electron injection characteristics of the anode 13.

  The anode 13 may be provided with a conductive layer for improving the adhesion between the anode 13 and the substrate 12 on the side in contact with the substrate 12. Examples of such a conductive layer include transparent conductive layers such as ITO and IZO.

  When the driving method of the display device configured using the organic electroluminescent element 11 is an active matrix method, the anode 13 is patterned for each pixel and connected to a driving thin film transistor provided on the substrate 12. It is provided in the state that was done. Further, in this case, although not shown here, an insulating film is provided on the anode 13, and the surface of the anode 13 of each pixel is exposed from the opening of the insulating film. And

<Hole Injection Layer 14a>
The hole injection layer 14a is for increasing the efficiency of hole injection into the light emitting layer 14c. Examples of the material constituting the hole injection layer 14a include benzine, styrylamine, triphenylamine, porphyrin, triphenylene, azatriphenylene, tetracyanoquinodimethane, triazole, imidazole, oxadiazole, and polyarylalkane. , Phenylenediamine, arylamine, oxazole, anthracene, fluorenone, hydrazone, stilbene or their derivatives, or heterocyclic conjugated monomers and oligomers such as polysilane compounds, vinylcarbazole compounds, thiophene compounds or aniline compounds Alternatively, a polymer can be used.

  Further, specific materials for such a hole injection layer 14a include α-naphthylphenylphenylenediamine, porphyrin, metal tetraphenylporphyrin, metal naphthalocyanine, hexacyanoazatriphenylene, 7,7,8,8-tetra. Cyanoquinodimethane (TCNQ), 7,7,8,8-tetracyano-2,3,5,6-tetrafluoroquinodimethane (F4-TCNQ), tetracyano 4,4,4-tris (3-methyl Phenylphenylamino) triphenylamine, N, N, N ′, N′-tetrakis (p-tolyl) p-phenylenediamine, N, N, N ′, N′-tetraphenyl-4,4′-diaminobiphenyl, N-phenylcarbazole, 4-di-p-tolylaminostilbene, poly (paraphenylene vinylene), poly (thiol Nbiniren), poly (2,2'-thienylpyrrole), and including without being limited thereto.

<Hole transport layer 14b>
The hole transport layer 14b is for increasing the efficiency of hole injection into the light emitting layer 14c similarly to the hole injection layer 14a, and may be a single layer structure or a multilayer structure composed of a plurality of layers. . In particular, the hole transport layer 14b portion in contact with the light emitting layer 14c is characterized in that it contains a blue light emitting dye together with a compound represented by the following general formula (1) or general formula (2). The blue light emitting dye contained in the hole transport layer 14b may be the same as the blue light emitting dye used as the constituent material of the light emitting layer 14c, and it is preferable to use the same material. Such a blue light-emitting dye will be described in detail in the next light-emitting layer 14c.

In general formula (1), Ar ¹ and Ar ² each independently represent an aromatic hydrocarbon ring group or an aromatic heterocyclic group. R ^{1 to} R ⁸ are each independently a hydrogen atom, halogen atom, alkyl group, aralkyl group, alkenyl group, cyano group, amino group, acyl group, alkoxycarbonyl group, carboxyl group, alkoxy group, aryloxy group. , An alkylsulfonyl group, a hydroxyl group, an amide group, an aromatic hydrocarbon ring group, or an aromatic heterocyclic group. Of these R ^{1 to} R ⁸ , adjacent ones may form a ring. X represents a linking group formed by bonding 1 to 4 divalent aromatic groups.

Examples of the aromatic hydrocarbon ring group represented by Ar ¹ and Ar ² in the general formula (1) include a group consisting of a single benzene ring or 2 to 5 condensed rings. Specific examples include a phenyl group, a naphthyl group, an anthryl group, a phenanthryl group, a pyrenyl group, and a perylenyl group. Examples of the aromatic heterocyclic group represented by Ar ¹ and Ar ² include a 5- or 6-membered monocyclic ring or a 2-5 condensed ring. Specific examples include a pyridyl group, a triazinyl group, a pyrazinyl group, a quinoxalinyl group, and a thienyl group.

Examples of the substituent that the aromatic hydrocarbon ring group and aromatic heterocyclic group represented by Ar ¹ and Ar ² may have include an alkyl group (for example, a straight chain having 1 to 6 carbon atoms such as a methyl group and an ethyl group). Or a branched alkyl group), an alkenyl group (for example, a linear or branched alkenyl group having 1 to 6 carbon atoms such as a vinyl group or an allyl group), an alkoxycarbonyl group (for example, a methoxycarbonyl group, an ethoxycarbonyl group, or the like) A linear or branched alkoxycarbonyl group having 1 to 6 carbon atoms, an alkoxy group (for example, a linear or branched alkoxy group having 1 to 6 carbon atoms such as a methoxy group or an ethoxy group), an aryloxy group (for example, a phenoxy group, Aryloxy group having 6 to 10 carbon atoms such as naphthoxy group), aralkyloxy group (for example, aryloxy having 7 to 13 carbon atoms such as benzyloxy group) ) Secondary or tertiary amino group (for example, a dialkylamino group having a linear or branched alkyl group having 2 to 20 carbon atoms such as diethylamino group or diisopropylamino group; diaryl such as diphenylamino group or phenylnaphthylamino group) Amino group; arylalkylamino group having 7 to 20 carbon atoms, such as methylphenylamino group, etc., halogen atom (fluorine atom, chlorine atom, bromine atom or iodine atom), aromatic hydrocarbon ring group (for example, phenyl group) An aromatic hydrocarbon ring group having 6 to 10 carbon atoms such as a naphthyl group) and an aromatic heterocyclic group (for example, a 5- or 6-membered monocyclic ring or a 2-condensed ring such as a thienyl group or a pyridyl group) Aromatic heterocyclic group), and the like. Among these, an alkyl group, an alkoxy group, an alkylamino group, an arylamino group, an arylalkylamino group, a halogen atom, an aromatic hydrocarbon ring group, and an aromatic heterocyclic group are preferable, and an alkyl group, an alkoxy group, an arylamino group Is particularly preferred.

When Ar ¹ and Ar ² have a structure containing three or more aromatic groups connected via two or more direct bonds, such as a terphenyl group, it is represented by —NAr ¹ Ar ^2. There is a possibility that the hole transporting ability of the arylamino group may decrease, and the Tg of the compound may decrease. Therefore, in order not to impair the properties of the compound according to the present invention, Ar ¹ and Ar ² are each composed of 3 or more aromatic groups bonded in series via a direct bond or a short chain linking group. It is important that there is no group.

R ^{1 to} R ^{8 in the} general formula (1) are each independently a hydrogen atom, a halogen atom (a fluorine atom, a chlorine atom, a bromine atom or an iodine atom), an alkyl group (for example, a methyl group, an ethyl group, etc.) A linear or branched alkyl group having 1 to 6 carbon atoms; a cycloalkyl group having 5 to 8 carbon atoms such as a cyclopentyl group or a cyclohexyl group; an aralkyl group (for example, a benzyl group or a phenethyl group; Aralkyl groups), alkenyl groups (e.g. vinyl or allyl groups, linear or branched alkenyl groups having 2 to 7 carbon atoms), cyano groups, amino groups, especially tertiary amino groups (e.g. diethylamino groups, diisopropylamino). A dialkylamino group having a linear or branched alkyl group having 2 to 20 carbon atoms, such as a diphenylamino group or a phenylnaphthylamino group; Reel amino group; arylalkylamino group having 7 to 20 carbon atoms such as methylphenylamino group, etc., acyl group (for example, acetyl group, propionyl group, benzoyl group, naphthoyl group, etc.) An acyl group containing a chain, branched or cyclic hydrocarbon group moiety), an alkoxycarbonyl group (eg, a linear or branched alkoxycarbonyl group having 2 to 7 carbon atoms such as a methoxycarbonyl group or an ethoxycarbonyl group), a carboxyl group, Alkoxy groups (for example, straight or branched alkoxy groups having 1 to 6 carbon atoms such as methoxy group and ethoxy group), aryloxy groups (for example, aryloxy groups having 6 to 10 carbon atoms such as phenoxy group and benzyloxy group) ), Alkylsulfonyl group (for example, methylsulfonyl group, ethylsulfonyl group, propylsulfonyl group) Alkyl group having 1 to 6 carbon atoms such as a benzene group, a butylsulfonyl group, and a hexylsulfonyl group), a hydroxyl group and an amide group (for example, a methylamide group, a dimethylamide group, a diethylamide group, etc.) Group; arylamide group such as benzylamide group, dibenzylamide group, etc.), aromatic hydrocarbon ring group (for example, phenyl group, naphthyl group, anthryl group, phenanthryl group, pyrenyl group, etc.) An aromatic hydrocarbon ring group composed of 2 to 4 condensed rings), or an aromatic heterocyclic group (for example, a carbazolyl group, a pyridyl group, a triazyl group, a pyrazyl group, a quinoxalyl group, a thienyl group, etc. An aromatic heterocyclic group consisting of a single ring or 2 to 3 condensed rings).

More preferable examples of R ^{1 to} R ⁸ include a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an aromatic hydrocarbon ring group, and an aromatic heterocyclic group.

The groups described above as examples of R ^{1 to} R ⁸ may further have a substituent, such as a halogen atom (a fluorine atom, a chlorine atom, a bromine atom or an iodine atom), an alkyl group (for example, a methyl group). Group, straight or branched alkyl group having 1 to 6 carbon atoms such as ethyl group), alkenyl group (for example, linear or branched alkenyl group having 1 to 6 carbon atoms such as vinyl group and allyl group), alkoxycarbonyl A group (for example, a linear or branched alkoxycarbonyl group having 1 to 6 carbon atoms such as a methoxycarbonyl group or an ethoxycarbonyl group), an alkoxy group (for example, a linear chain having 1 to 6 carbon atoms such as a methoxy group or an ethoxy group) A branched alkoxy group), an aryloxy group (for example, an aryloxy group having 6 to 10 carbon atoms such as a phenoxy group or a naphthoxy group), a dialkylamino group (for example, Dialkylamino groups having a linear or branched alkyl group having 2 to 20 carbon atoms such as ethylamino group and diisopropylamino group), diarylamino groups (diarylamino groups such as diphenylamino group and phenylnaphthylamino group), aromatic Aromatic hydrocarbon ring groups (for example, aromatic hydrocarbon ring groups such as phenyl groups) and aromatic heterocyclic groups (for example, thienyl groups, pyridyl groups, etc., 5- or 6-membered monocyclic aromatic heterocyclic groups ), An acyl group (for example, an acetyl group, a propionyl group, etc., a straight-chain or branched acyl group having 1 to 6 carbon atoms), a haloalkyl group (for example, a trifluoromethyl group, etc. Haloalkyl group), cyano group and the like. Of these, a halogen atom, an alkoxy group, and an aromatic hydrocarbon ring group are more preferable.

Moreover, R < ¹ > -R < ⁸ > may combine with adjacent things and may form the ring condensed to N-carbazolyl group. Of R ¹ to R ⁸ , the ring formed by bonding of adjacent groups is usually a 5- to 8-membered ring, preferably a 5- or 6-membered ring, more preferably a 6-membered ring. This ring may be an aromatic ring or a non-aromatic ring, but is preferably an aromatic ring. Furthermore, it may be an aromatic hydrocarbon ring or an aromatic heterocyclic ring, but is preferably an aromatic hydrocarbon ring.

As an example of forming a condensed ring that forms a ring with the adjacent ones of R ^{1 to} R ⁸ as described above and is bonded to the N-carbazolyl group, for example, the following condensed rings (1) a to (1) d: Is exemplified.

However, it is particularly preferable that all of R ¹ to R ⁸ are hydrogen atoms (that is, the N-carbazolyl group is unsubstituted), or one or more of R ¹ to R ⁸ are a methyl group, a phenyl group, One of the methoxy groups, and the remainder is a hydrogen atom.

  X in the general formula (1) represents a linking group formed by bonding 1 to 4 divalent aromatic groups which may have a substituent.

Preferred examples of the linking group X as described above include —Ar ³ —, —Ar ⁴ —Ar ⁵ —, —Ar ⁶ —Ar ⁷ —Ar ⁸ —, or —Ar ⁹ —Ar ¹⁰ —Ar ¹¹ —Ar ¹² —. It is represented by

Ar ³ , Ar ⁴ , Ar ⁵ , Ar ⁶ , Ar ⁸ , Ar ⁹ and Ar ¹² constituting the terminal of these linking groups X are optionally substituted monocyclic aromatic rings having 5 to 6 members Or the bivalent group which consists of a 2-5 condensed ring is represented. Of these, Ar ⁸ , Ar ⁹ and Ar ^{12 each} represent an optionally substituted divalent group consisting of a monocyclic or 2-5 condensed ring having 5-6 members, or —NAr ¹³ — (wherein Ar ¹³ represents an optionally substituted monovalent aromatic hydrocarbon ring group or aromatic heterocyclic group).

Specific examples of Ar ³ , Ar ⁴ , Ar ⁵ , Ar ⁶ , Ar ⁸ , Ar ⁹ and Ar ¹² constituting the terminal of the linking group X as described above include a phenylene group, a naphthylene group, an anthrylene group, a phenanthrylene group, Examples thereof include divalent aromatic hydrocarbon ring groups such as pyrenylene group and peryleneylene group, and divalent aromatic heterocyclic groups such as pyridylene group, triadylene group, pyrazylene group, quinoxalylene group, thienylene group, and oxadiazolylene group.

Ar ⁷ , Ar ¹⁰ and Ar ¹¹ constituting the center of the linking group X are divalent aromatic groups represented by the groups described above as Ar ^{3 and the} like constituting the terminal, or —NAr ¹³ — It is a divalent arylamino group represented. Ar ¹³ represents a monovalent aromatic hydrocarbon ring group or aromatic heterocyclic group which may have a substituent. Examples of such Ar ¹³ include 5- or 6-membered aromatic groups such as phenyl group, naphthyl group, anthryl group, phenanthyl group, thienyl group, pyridyl group, carbazolyl group, and the like. You may have.

Ar ³ which is the smallest linking group as X is preferably 3 or more condensed rings in order to improve the rigidity of the compound and the heat resistance resulting therefrom.

Ar ⁴ , Ar ⁵ , Ar ⁶ , Ar ⁸ , Ar ⁹ and Ar ¹² are preferably a single ring or a 2-3 condensed ring, and more preferably a single ring or a 2 condensed ring.

From the viewpoint of improving heat resistance, Ar ⁷ , Ar ¹⁰ and Ar ¹¹ are preferably aromatic rings. Further, Ar ⁷ , Ar ¹⁰ and Ar ¹¹ are preferably —NAr ¹³ — from the viewpoint of improving the amorphous nature of the compound. By setting Ar ⁷ , Ar ¹⁰ and Ar ¹¹ to —NAr ¹³ —, the emission wavelength of the compound can be slightly increased, and a desired emission wavelength can be easily obtained. In addition, when one of Ar ¹⁰ and Ar ¹¹ is —NAr ¹³ —, the other is preferably an aromatic group.

Examples of the substituent that Ar ³ to Ar ¹² may have include the same groups as those described above as the substituent that each group exemplified as R ^{1 to} R ⁸ may have. Among them, an alkyl group, an alkoxy group, an aromatic hydrocarbon ring group, or an aromatic heterocyclic group is particularly preferable.

Examples of the substituent that Ar ¹³ may have include the same groups as those described above as the substituent that each group exemplified as R ^{1 to} R ⁸ may have. Among them, an arylamino group, an aromatic hydrocarbon ring group such as a phenyl group or a naphthyl group, or an aromatic heterocyclic group such as a carbazolyl group is particularly preferable.

  As specific examples of the compound represented by the general formula (1), the following compounds (1) -1 to (1) -26 are shown.

Next, in the general formula (2), X ¹ and X ² each independently represent an N-carbazoyl group, an N-phenoxadiyl group, or an N-phenothiadiyl group. In addition, X ² may be -NAR ³ AR ⁴ (AR ³ and AR ⁴ are heterocyclic aromatic groups).

When X ¹ and X ² are an N-carbazoyl group, an N-phenoxadiyl group, or an N-phenothiadiyl group, these may be unsubstituted or substituted with other substituents. When these are substituted with other substituents, the substituent is a halogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or an aryl group having 6 to 10 carbon atoms. It may be monosubstituted or polysubstituted.

  Preferred examples of these are unsubstituted or monosubstituted as a substituent, for example, a halogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or an aryl group having 6 to 10 carbon atoms. Or an optionally substituted N-carbazoyl group, N-phenoxadiyl group, or N-phenothiadiyl group. More preferably, it may be unsubstituted or monosubstituted or polysubstituted by a halogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or an aryl group having 6 to 10 carbon atoms. An N-carbazoyl group, an N-phenoxadiyl group, or an N-phenothiadiyl group, and more preferably an unsubstituted N-carbazoyl group, an unsubstituted N-phenoxadiyl group, or an unsubstituted N-phenothiadiyl group. is there.

Specific examples of the substituted or unsubstituted N-carbazoyl group, substituted or unsubstituted N-phenoxadiyl group, or substituted or unsubstituted N-phenothiadiyl group to be X ¹ and X ² include, for example, N-carbazoyl Group, 2-methyl-N-carbazoyl group, 3-methyl-N-carbazoyl group, 4-methyl-N-carbazoyl group, 3-n-butyl-N-carbazoyl group, 3-n-hexyl-N-carbazoyl group 3-n-octyl-N-carbazoyl group, 3-n-decyl-N-carbazoyl group, 3,6-dimethyl-N-carbazoyl group, 2-methoxy-N-carbazoyl group, 3-methoxy-N-carbazoyl group Group, 3-ethoxy-N-carbazoyl group, 3-isopropoxy-N-carbazoyl group, 3-n-butoxy-N-carbazoyl group, 3-n-octyl Tyloxy-N-carbazoyl group, 3-n-decyloxy-N-carbazoyl group, 3-phenyl-N-carbazoyl group, 3- (4′-methylphenyl) -N-carbazoyl group, 3-chloro-N-carbazoyl group N-phenoxadiyl group, N-phenothiadiyl group, 2-methyl-N-phenothiadiyl group, and the like.

Further, when X ² is —NAR ³ AR ⁴ (AR ³ and AR ⁴ are heterocyclic aromatic groups), the heterocyclic aromatic group of AR ³ and AR ⁴ is a halogen atom, an alkyl group as a substituent. A carbocyclic aromatic group having a total of 6 to 20 carbon atoms, which may be mono- or poly-substituted with a group, an alkoxy group, or an aryl group.

The heterocyclic aromatic group of AR ³ and AR ⁴ is, for example, a carbocyclic aromatic group such as a phenyl group, a naphthyl group or an anthryl group, for example, a heterocyclic fragrance such as a furyl group, a thienyl group or a pyridyl group. Represents a group. AR ³ and AR ⁴ are preferably unsubstituted or have a total carbon number of 6 to 20, which may be mono- or poly-substituted with, for example, a halogen atom, an alkyl group, an alkoxy group, or an aryl group as a substituent. A carbocyclic aromatic group or a heterocyclic aromatic group having 3 to 20 carbon atoms in total. More preferable examples of AR ³ and AR ⁴ are unsubstituted or monosubstituted with a halogen atom, an alkyl group having 1 to 14 carbon atoms, an alkoxy group having 1 to 14 carbon atoms, or an aryl group having 6 to 10 carbon atoms. Or a carbocyclic aromatic group having 6 to 20 carbon atoms which may be polysubstituted, more preferably unsubstituted or a halogen atom, an alkyl group having 1 to 4 carbon atoms, or 1 to 4 carbon atoms. Or a C6-C16 carbocyclic aromatic group which may be mono-substituted or poly-substituted with an aryl group having 6 to 10 carbon atoms.

Specific examples of such AR ³ and AR ⁴ include, for example, phenyl group, 1-naphthyl group, 2-naphthyl group, 2-anthryl group, 9-anthryl group, 4-quinolyl group, 4-pyridyl group, 3 -Pyridyl group, 2-pyridyl group, 3-furyl group, 2-furyl group, 3-thienyl group, 2-thienyl group, 2-oxazolyl group, 2-thiazolyl group, 2-benzoxazolyl group, 2-benzothiazolyl Group, 2-benzimidazolyl group, 4-methylphenyl group, 3-methylphenyl group, 2-methylphenyl group, 4-ethylphenyl group, 3-ethylphenyl group, 2-ethylphenyl group, 4-n-propylphenyl group 4-isopropylphenyl group, 2-isopropylphenyl group, 4-n-butylphenyl group, 4-isobutylphenyl group, 4-sec-butylphenyl group, -Sec -butylphenyl group, 4-tert-butylphenyl group, 3-tert-butylphenyl group, 2-tert-butylphenyl group, 4-n-pentylphenyl group, 4-isopentylphenyl group, 2-neopentyl group Phenyl group, 4-tert-pentylphenyl group, 4-n-hexylphenyl group, 4- (2′-ethylbutyl) phenyl group, 4-n-heptylphenyl group, 4-n-octylphenyl group, 4- (2 '-Ethylhexyl) phenyl group, 4-tert-octylphenyl group, 4-n-decylphenyl group, 4-n-dodecylphenyl group, 4-n-tetradecylphenyl group, 4-cyclopentylphenyl group, 4-cyclohexylphenyl Group, 4- (4′-methylcyclohexyl) phenyl group, 4- (4′-tert-butylcyclohexyl) phenyl group, 3-cyclohexylsulfate Nyl group, 2-cyclohexylphenyl group, 4-ethyl-1-naphthyl group, 6-n-butyl-2-naphthyl group, 2,4-dimethylphenyl group, 2,5-dimethylphenyl group, 3,4-dimethyl Phenyl group, 3,5-dimethylphenyl group, 2,6-dimethylphenyl group, 2,4-diethylphenyl group, 2,3,5-trimethylphenyl group, 2,3,6-trimethylphenyl group, 3,4 , 5-trimethylphenyl group, 2,6-diethylphenyl group, 2,5-diisopropylphenyl group, 2,6-diisobutylphenyl group, 2,4-di-tert-butylphenyl group, 2,5-di-tert -Butylphenyl group, 4,6-di-tert-butyl-2-methylphenyl group, 5-tert-butyl-2-methylphenyl group, 4-tert-butyl-2,6-dimethylphenyl group, 4- Methoxyphenyl group, 3-methoxyphenyl group, 2-methoxyphenyl group, 4-ethoxyphenyl group, 3-ethoxyphenyl group, 2-ethoxyphenyl group, 4-n-propoxyphenyl group, 3-n-propoxyphenyl group, 4-isopropoxyphenyl group, 2-isopropoxyphenyl group, 4-n-butoxyphenyl group, 4-isobutoxyphenyl group, 2-sec-butoxyphenyl group, 4-n-pentyloxyphenyl group, 4-isopentyl Oxyphenyl group, 2-isopentyloxyphenyl group, 4-neopentyloxyphenyl group, 2-neopentyloxyphenyl group, 4-n-hexyloxyphenyl group, 2- (2′-ethylbutyl) oxyphenyl group, 4 -N-octyloxyphenyl group, 4-n-decyloxyphenyl group, 4-n- Decyloxyphenyl group, 4-n-tetradecyloxyphenyl group, 4-cyclohexyloxyphenyl group, 2-cyclohexyloxyphenyl group, 2-methoxy-1-naphthyl group, 4-methoxy-1-naphthyl group, 4-n -Butoxy-1-naphthyl group, 5-ethoxy-1-naphthyl group, 6-methoxy-2-naphthyl group, 6-ethoxy-2-naphthyl group, 6-n-butoxy-2-naphthyl group, 6-n- Hexyloxy-2-naphthyl group, 7-methoxy-2-naphthyl group, 7-n-butoxy-2-naphthyl group, 2-methyl-4-methoxyphenyl group, 2-methyl-5-methoxyphenyl group, 3- Methyl-5-methoxyphenyl group, 3-ethyl-5-methoxyphenyl group, 2-methoxy-4-methylphenyl group, 3-methoxy-4-methylphenyl Group, 2,4-dimethoxyphenyl group, 2,5-dimethoxyphenyl group, 2,6-dimethoxyphenyl group, 3,4-dimethoxyphenyl group, 3,5-dimethoxyphenyl group, 3,5-diethoxyphenyl Group, 3,5-di-n-butoxyphenyl group, 2-methoxy-4-ethoxyphenyl group, 2-methoxy-6-ethoxyphenyl group, 3,4,5-trimethoxyphenyl group, 4-phenylphenyl group 3-phenylphenyl group, 2-phenylphenyl group, 4- (4′-methylphenyl) phenyl group, 4- (3′-methylphenyl) phenyl group, 4- (4′-methoxyphenyl) phenyl group, 4 -(4'-n-butoxyphenyl) phenyl group, 2- (2'-methoxyphenyl) phenyl group, 4- (4'-chlorophenyl) phenyl group, 3-methyl-4-phenyl Nylphenyl group, 3-methoxy-4-phenylphenyl group, 4-fluorophenyl group, 3-fluorophenyl group, 2-fluorophenyl group, 4-chlorophenyl group, 3-chlorophenyl group, 2-chlorophenyl group, 4-bromophenyl Group, 2-bromophenyl group, 4-chloro-1-naphthyl group, 4-chloro-2-naphthyl group, 6-bromo-2-naphthyl group, 2,3-difluorophenyl group, 2,4-difluorophenyl group 2,5-difluorophenyl group, 2,6-difluorophenyl group, 3,4-difluorophenyl group, 3,5-difluorophenyl group, 2,3-dichlorophenyl group, 2,4-dichlorophenyl group, 2,5 -Dichlorophenyl group, 3,4-dichlorophenyl group, 3,5-dichlorophenyl group, 2,5-dibromophenyl 2,4,6-trichlorophenyl group, 2,4-dichloro-1-naphthyl group, 1,6-dichloro-2-naphthyl group, 2-fluoro-4-methylphenyl group, 2-fluoro-5-methyl Phenyl group, 3-fluoro-2-methylphenyl group, 3-fluoro-4-methylphenyl group, 2-methyl-4-fluorophenyl group, 2-methyl-5-fluorophenyl group, 3-methyl-4-fluoro Phenyl group, 2-chloro-4-methylphenyl group, 2-chloro-5-methylphenyl group, 2-chloro-6-methylphenyl group, 2-methyl-3-chlorophenyl group, 2-methyl-4-chlorophenyl group 3-methyl-4-chlorophenyl group, 2-chloro-4,6-dimethylphenyl group, 2-methoxy-4-fluorophenyl group, 2-fluoro-4-methoxyphenyl Phenyl group, 2-fluoro-4-ethoxyphenyl group, 2-fluoro-6-methoxyphenyl group, 3-fluoro-4-ethoxyphenyl group, 3-chloro-4-methoxyphenyl group, 2-methoxy-5-chlorophenyl Group, 3-methoxy-6-chlorophenyl group, 5-chloro-2,4-dimethoxyphenyl group and the like, but are not limited thereto.

B ¹ and B ² in the general formula (2) are each independently a hydrogen atom, a linear, branched or cyclic alkyl group, a carbocyclic aromatic group having 6 to 20 carbon atoms, and a total of 3 carbon atoms. -20 heterocyclic aromatic groups or aralkyl groups. When B ¹ and B ² are carbocyclic aromatic groups, heterocyclic aromatic groups, or aralkyl groups, these may be unsubstituted or substituted with other substituents. When these are substituted with other substituents, they may be mono- or polysubstituted with a halogen atom, an alkyl group, an alkoxy group, or an aryl group.

B ¹ and B ² as described above are preferably a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 16 carbon atoms, a substituted or unsubstituted aryl group having 4 to 16 carbon atoms, or carbon. A substituted or unsubstituted aralkyl group having 5 to 16 carbon atoms, more preferably a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 8 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 12 carbon atoms. Or a substituted or unsubstituted aralkyl group having 7 to 12 carbon atoms. Still more preferably, B ¹ and B ² are a linear, branched or cyclic alkyl group having 1 to 8 carbon atoms, a carbocyclic aromatic group having 6 to 10 carbon atoms, or a carbocyclic group having 7 to 10 carbon atoms. Represents an aralkyl group.

Specific examples of the linear, branched or cyclic alkyl group for B ¹ and B ² include, for example, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, tert-butyl group, n-pentyl group, isopentyl group, neopentyl group, tert-pentyl group, cyclopentyl group, n-hexyl group, 2-ethylbutyl group, 3,3-dimethylbutyl group, cyclohexyl group, n-heptyl group, Examples include cyclohexylmethyl group, n-octyl group, tert-octyl group, 2-ethylhexyl group, n-nonyl group, n-decyl group, n-dodecyl group, n-tetradecyl group, n-hexadecyl group and the like. Specific examples of the substituted or unsubstituted aryl group for B ¹ and B ² include, for example, the substituted or unsubstituted aryl groups listed as specific examples for AR ³ and AR ^4. It is not limited to.

Specific examples of the substituted or unsubstituted aralkyl group for B ¹ and B ² include, for example, benzyl group, phenethyl group, α-methylbenzyl group, α, α-dimethylbenzyl group, 1-naphthylmethyl group, 2 -Naphthylmethyl group, furfuryl group, 2-methylbenzyl group, 3-methylbenzyl group, 4-methylbenzyl group, 4-ethylbenzyl group, 4-isopropylbenzyl group, 4-tert-butylbenzyl group, 4-n- Hexylbenzyl group, 4-nonylbenzyl group, 3,4-dimethylbenzyl group, 3-methoxybenzyl group, 4-methoxybenzyl group, 4-ethoxybenzyl group, 4-n-butoxybenzyl group, 4-n-hexyloxy Benzyl group, 4-nonyloxybenzyl group, 4-fluorobenzyl group, 3-fluorobenzyl group, 2-chlorobenzyl group, 4- And the like can be mentioned aralkyl groups such as Rorobenjiru groups, but is not limited thereto.

Z ¹ and Z ² in the general formula (2) are each independently a hydrogen atom, a halogen atom, a linear, branched or cyclic alkyl group, a linear, branched or cyclic alkoxy group, and a total of 6 to 6 carbon atoms. It represents a carbocyclic aromatic group having 20 carbon atoms or a heterocyclic aromatic group having 3 to 20 carbon atoms in total. When Z ¹ and Z ² are carbocyclic aromatic groups or heterocyclic aromatic groups, they may be unsubstituted or substituted with other substituents. When these are substituted with other substituents, they may be mono- or poly-substituted with a halogen atom, an alkyl group, an alkoxy group, or an aryl group as the substituent.

Z ¹ and Z ² as described above are preferably a hydrogen atom, a halogen atom, a linear, branched or cyclic alkyl group having 1 to 16 carbon atoms, a linear, branched or cyclic alkoxy group having 1 to 16 carbon atoms. Group, or a substituted or unsubstituted aryl group having 4 to 20 carbon atoms, more preferably a hydrogen atom, a halogen atom, a linear, branched or cyclic alkyl group having 1 to 8 carbon atoms, or 1 to 8 carbon atoms. A linear, branched or cyclic alkoxy group, or a substituted or unsubstituted aryl group having 6 to 12 carbon atoms, and more preferably a hydrogen atom.

As specific examples of the linear, branched or cyclic alkyl groups of Z ¹ and Z ² , for example, the linear, branched or cyclic alkyl groups mentioned as specific examples of R ₁ and R ₂ may be exemplified. it can. Specific examples of the substituted or unsubstituted aryl group for Z ¹ and Z ² include the substituted or unsubstituted aryl groups listed as specific examples for AR ³ and AR ⁴ .

Specific examples of the halogen atom of Z ¹ and Z ² , a linear, branched or cyclic alkoxy group include, for example, halogen atoms such as fluorine atom, chlorine atom and bromine atom, such as methoxy group, ethoxy group and n-propoxy Group, isopropoxy group, n-butoxy group, isobutoxy group, sec-butoxy group, n-pentyloxy group, isopentyloxy group, neopentyloxy group, cyclopentyloxy group, n-hexyloxy group, 2-ethylbutoxy group 3,3-dimethylbutoxy group, cyclohexyloxy group, n-heptyloxy group, cyclohexylmethyloxy group, n-octyloxy group, 2-ethylhexyloxy group, n-nonyloxy group, n-decyloxy group, n-dodecyloxy Group, n-tetradecyloxy group, n-hexadecyloxy group, etc. It can be mentioned carboxy group.

  As specific examples of the compound represented by the general formula (2), the following compounds (2) -1 to (2) -100 are shown.

  When the hole transport layer 14b including the general formula (1) or the general formula (2) and the blue light-emitting dye as described above has a laminated structure, a layer including these materials is provided in contact with the light-emitting layer 14c. It is done. And the other layer which comprises the positive hole transport layer 14b is comprised using the material selected suitably from the material demonstrated by the positive hole injection layer 14a mentioned above.

<Light emitting layer 14c>
In the present embodiment, the light emitting layer 14c is doped with a blue light emitting dye using an anthracene compound as a host material, and emits blue light. Hereinafter, the host material and the blue light emitting dye will be described in this order.

  As the host material constituting the light emitting layer 14c, an anthracene derivative represented by the following general formula (3) is preferably used as the host material.

However, in the general formula (3), R ^{11 to} R ¹⁶ are each independently hydrogen, halogen, hydroxyl group, substituted or unsubstituted carbonyl group having 20 or less carbon atoms, substituted or unsubstituted carbon group having 20 or less carbon atoms. Carbonyl ester group, substituted or unsubstituted alkyl group having 20 or less carbon atoms, substituted or unsubstituted alkenyl group having 20 or less carbon atoms, substituted or unsubstituted alkoxyl group having 20 or less carbon atoms, cyano group, nitro group, carbon A substituted or unsubstituted silyl group having 30 or fewer carbon atoms, a substituted or unsubstituted aryl group having 30 or fewer carbon atoms, a substituted or unsubstituted heterocyclic group having 30 or fewer carbon atoms, or a substituted or unsubstituted carbon group having 30 or fewer carbon atoms An amino group is shown.

The aryl group represented by R ^{11 to} R ¹⁶ in the general formula (3) is, for example, a phenyl group, 1-naphthyl group, 2-naphthyl group, fluorenyl group, 1-anthryl group, 2-anthryl group, 9-anthryl group, 1-phenanthryl group, 2-phenanthryl group, 3-phenanthryl group, 4-phenanthryl group, 9-phenanthryl group, 1-naphthacenyl group, 2-naphthacenyl group, 9-naphthacenyl group, 1-pyrenyl group, 2-pyrenyl group, 4-pyrenyl group, 1-chrycenyl group, 6-chrycenyl group, 2-fluoranthenyl group, 3-fluoranthenyl group, 2-biphenylyl group, 3-biphenylyl group, 4-biphenylyl group, o-tolyl Group, m-tolyl group, p-tolyl group, pt-butylphenyl group and the like.

The heterocyclic group represented by R ^{11 to} R ¹⁶ is a 5- or 6-membered aromatic heterocyclic group containing O, N or S as a hetero atom, or a condensed polycyclic aromatic heterocyclic group having 2 to 20 carbon atoms. Is mentioned. These aromatic heterocyclic groups and condensed polycyclic aromatic heterocyclic groups include thienyl group, furyl group, pyrrolyl group, pyridyl group, quinolyl group, quinoxalyl group, imidazopyridyl group, and benzothiazole group. Representative examples include 1-pyrrolyl group, 2-pyrrolyl group, 3-pyrrolyl group, pyrazinyl group, 2-pyridinyl group, 3-pyridinyl group, 4-pyridinyl group, 1-indolyl group, 2-indolyl group, 3-indolyl group, 4-indolyl group, 5-indolyl group, 6-indolyl group, 7-indolyl group, 1-isoindolyl group, 2-isoindolyl group, 3-isoindolyl group, 4-isoindolyl group, 5-isoindolyl group, 6-isoindolyl group, 7-isoindolyl group, 2-furyl group, 3-furyl group, 2-benzofuranyl group, 3-benzofuranyl group, 4-benzofuranyl group, 5-benzofuranyl group, 6-benzofuranyl group, 7-benzofuranyl group, 1-isobenzofuranyl group, 3-isobenzofuranyl group, 4-isobenzofuranyl group, 5-isobenzofuranyl group Zofuranyl group, 6-isobenzofuranyl group, 7-isobenzofuranyl group, quinolyl group, 3-quinolyl group, 4-quinolyl group, 5-quinolyl group, 6-quinolyl group, 7-quinolyl group, 8-quinolyl group Group, 1-isoquinolyl group, 3-isoquinolyl group, 4-isoquinolyl group, 5-isoquinolyl group, 6-isoquinolyl group, 7-isoquinolyl group, 8-isoquinolyl group, 2-quinoxalinyl group, 5-quinoxalinyl group, 6-quinoxalinyl group Group, 1-carbazolyl group, 2-carbazolyl group, 3-carbazolyl group, 4-carbazolyl group, 9-carbazolyl group, 1-phenanthridinyl group, 2-phenanthridinyl group, 3-phenanthridinyl group 4-phenanthridinyl group, 6-phenanthridinyl group, 7-phenanthridinyl group, 8-phenanthridinyl group, 9 Phenanthridinyl group, 10-phenanthridinyl group, 1-acridinyl group, 2-acridinyl group, 3-acridinyl group, 4-acridinyl group, 9-acridinyl group, and the like.

The amino group represented by R ^{11 to} R ¹⁶ may be an alkylamino group, an arylamino group, an aralkylamino group, or the like. These preferably have an aliphatic having 1 to 6 carbon atoms in total and / or an aromatic carbocyclic ring having 1 to 4 rings. Examples of such a group include a dimethylamino group, a diethylamino group, a dibutylamino group, a diphenylamino group, a ditolylamino group, a bisbiphenylylamino group, and a dinaphthylamino group.

  Two or more of the above substituents may form a condensed ring, and may further have a substituent.

  As specific examples of the anthracene derivative used as the host material as described above, the following compounds (3) -1 to (3) -50 are shown.

  Further, as the blue light emitting dye material constituting the light emitting layer 14c, a material having high luminous efficiency, for example, a low molecular fluorescent dye, a fluorescent polymer, and an organic light emitting material such as a metal complex is used.

  Here, the blue light-emitting dye material indicates a compound having a peak in the light emission wavelength range of about 400 nm to 490 nm, and is the same as that contained in the hole transport layer 14b described above. As such a compound, an organic substance such as a naphthalene derivative, anthracene derivative, naphthacene derivative, styrylamine derivative, or bis (azinyl) methene boron complex is used. Among these, it is preferable to select from aminonaphthalene derivatives, aminoanthracene derivatives, aminochrysene derivatives, aminopyrene derivatives, styrylamine derivatives, and bis (azinyl) methene boron complexes.

  Of these, aminochrysene derivatives represented by the following general formula (4) are preferably used.

However, R ^{21 to} R ³⁰ in the general formula (4) are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 20 carbon atoms. A group or a cyano group.

A _{1 to} A ₄ in formula (4) are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, or a substituted or unsubstituted aryl group having 5 to 50 carbon atoms. Group, substituted or unsubstituted cycloalkyl group having 3 to 50 nuclear carbon atoms, substituted or unsubstituted alkoxyl group having 1 to 50 carbon atoms, substituted or unsubstituted aryloxy group having 5 to 50 nuclear carbon atoms, substituted or An unsubstituted arylamino group having 5 to 50 carbon atoms, a substituted or unsubstituted alkylamino group having 1 to 20 carbon atoms, or a halogen atom;

Moreover, m of A < ₁ > -A < ₄ > represents the integer of 0-5 each independently. When m is 2 or more, A _{1 to} A ₄ may be the same as or different from each other, and may be connected to each other to form a saturated or unsaturated ring. A ₁ and A ₂ , A ₃ and A ₄ may be connected to each other to form a saturated or unsaturated ring. However, the case where all of A _{1 to} A ₄ are hydrogen atoms in the general formula (4) is not included.

  The following compounds (4) -1 to (4) -27 are shown as specific examples of aminochrysene derivatives used as the blue light-emitting dyes as described above.

<Electron transport layer 14d>
The electron transport layer 14d is for transporting electrons injected from the cathode 15 to the light emitting layer 14c. Examples of the material for the electron transport layer 14d include quinoline, perylene, phenanthroline, bisstyryl, pyrazine, triazole, oxazole, oxadiazole, fluorenone, and derivatives or metal complexes thereof. Specifically, tris (8-hydroxyquinoline) aluminum (abbreviated as Alq3), anthracene, naphthalene, phenanthrene, pyrene, anthracene, perylene, butadiene, coumarin, acridine, stilbene, 1,10-phenanthroline, or derivatives or metal complexes thereof. Is mentioned.

  Each layer constituting the organic layer 14 as described above, for example, the hole injection layer 14a, the hole transport layer 14b, the light emitting layer 14c, and the electron transport layer 14d may have a laminated structure including a plurality of layers, The hole transport layer 14b portion in contact with the light emitting layer 14c contains the compound of the general formula (1) or the general formula (2) and a blue light emitting dye.

<Cathode 15>
Next, the cathode 15 provided on the organic layer 14 having such a configuration has, for example, a two-layer structure in which a first layer 15a and a second layer 15b are stacked in this order from the organic layer 14 side.

The first layer 15a is made of a material having a small work function and good light transmittance. Examples of such a material include lithium oxide (Li ₂ O) which is an oxide of lithium (Li), cesium carbonate (Cs ₂ CO ₃ ) which is a composite oxide of cesium (Cs), and further oxidation of these. Mixtures of oxides and composite oxides can be used. Further, the first layer 15a is not limited to such a material. For example, alkaline earth metals such as calcium (Ca) and barium (Ba), alkali metals such as lithium and cesium, and indium ( In), magnesium (Mg), and other metals having a low work function, and oxides and composite oxides, fluorides, and the like of these metals alone or these metals, oxides and composite oxides, You may use it, improving stability as a mixture or an alloy.

  The second layer 15b is constituted by a thin film using a light-transmitting layer such as MgAg. The second layer 15b may be a mixed layer containing an organic light emitting material such as an aluminum quinoline complex, a styrylamine derivative, or a phthalocyanine derivative. In this case, a layer having optical transparency such as MgAg may be additionally provided as the third layer.

  The cathode 15 as described above is formed in a solid film shape on the substrate 12 when the driving method of a display device configured using the organic electroluminescent element 11 is an active matrix method, and serves as a common electrode of each pixel. Used. In this case, the cathode 15 is provided in a state of being insulated from the anode 13 by the organic layer 14 and an insulating film not shown here.

  Needless to say, the cathode 15 is not limited to the laminated structure as described above, and an optimum combination and laminated structure may be adopted according to the structure of the device to be manufactured. For example, the configuration of the cathode 15 of the above embodiment includes an inorganic layer (first layer 15a) that promotes functional separation of each electrode layer, that is, electron injection into the organic layer 14, and an inorganic layer (second layer 15b) that controls the electrode. Is a laminated structure in which and are separated. However, the inorganic layer that promotes electron injection into the organic layer 14 may also serve as the inorganic layer that controls the electrode, and these layers may be configured as a single layer structure. Moreover, it is good also as a laminated structure which formed transparent electrodes, such as ITO, on this single layer structure.

  The current applied to the organic electroluminescent element 11 having the above-described configuration is usually a direct current, but a pulse current or an alternating current may be used. The current value and the voltage value are not particularly limited as long as the element is not destroyed. However, considering the power consumption and life of the organic electroluminescent element, it is desirable to emit light efficiently with as little electrical energy as possible.

  Further, when the organic electroluminescent element 11 has a cavity structure, the cathode 15 is configured using a transflective material. Then, light emitted by multiple interference between the light reflecting surface on the anode 13 side and the light reflecting surface on the cathode 15 side is extracted from the cathode 15 side. In this case, the optical distance between the light reflecting surface on the anode 13 side and the light reflecting surface on the cathode 15 side is defined by the wavelength of light to be extracted, and the film thickness of each layer is set so as to satisfy this optical distance. Suppose that it is done. In such a top emission type organic electroluminescence device, it is possible to improve the light extraction efficiency to the outside and control the emission spectrum by positively using this cavity structure.

  Furthermore, although illustration is omitted here, the organic electroluminescent element 11 having such a configuration is covered with a protective layer (passivation layer) in order to prevent deterioration of the organic material due to moisture, oxygen, etc. in the atmosphere. It is preferable to use in. The protective film includes silicon nitride (typically Si3N4), silicon oxide (typically SiO2) film, silicon nitride oxide (SiNxOy: composition ratio X> Y) film, silicon oxynitride (SiOxNy: composition ratio) X> Y) film, a thin film mainly composed of carbon such as DLC (Diamond like Carbon), a CN (Carbon Nanotube) film, or the like is used. These films are preferably single-layered or laminated. Among these, a protective layer made of nitride is preferably used because it has a dense film quality and has an extremely high blocking effect against moisture, oxygen, and other impurities that adversely affect the organic electroluminescent element 11.

  In the above embodiment, the present invention has been described in detail by exemplifying a case where the organic electroluminescent element is a top emission type. However, the organic electroluminescence device of the present invention is not limited to the application to the top emission type, and can be widely applied to a configuration in which an organic layer having at least a light emitting layer is sandwiched between an anode and a cathode. It is. Therefore, in order from the substrate side, the cathode, the organic layer, and the anode are laminated in sequence, and the electrode located on the substrate side (lower electrode as the cathode or anode) is made of a transparent material and located on the opposite side of the substrate The electrode (upper electrode as a cathode or anode) is made of a reflective material, so that it can be applied to a bottom emission type (so-called transmission type) organic electroluminescence device in which light is extracted only from the lower electrode side. is there.

  Furthermore, the organic electroluminescent element of the present invention may be an element formed by a pair of electrodes (anode and cathode) and an organic layer sandwiched between the electrodes. For this reason, it is not limited to what comprised only a pair of electrode and organic layer, and other components (for example, an inorganic compound layer and an inorganic component) coexist in the range which does not impair the effect of this invention. Is not to be excluded.

  And as demonstrated above, in the organic electroluminescent element 11 of embodiment made into a structure in which a positive hole transport layer contains a blue luminescent pigment | dye with General formula (1) or General formula (2), it is demonstrated in detail by a subsequent example. As will be described, it was found that a long lifetime can be obtained as a result of the high current efficiency as compared with the case where the hole transport layer does not contain a blue light-emitting dye and the reduction of the current load.

  As a result, according to the present invention, it is possible to obtain a blue light-emitting organic electroluminescent device with good luminous efficiency, thereby reducing the current load for ensuring luminance in organic electroluminescence viewing and reducing the lifetime. It becomes possible to improve the characteristics.

≪Schematic configuration of display device≫
2A and 2B are diagrams illustrating an example of the display device 10 according to the embodiment. FIG. 2A is a schematic configuration diagram, and FIG. 2B is a configuration diagram of a pixel circuit. Here, an embodiment in which the present invention is applied to an active matrix display device 10 using an organic electroluminescent element 11 as a light emitting element will be described.

  As shown in FIG. 2A, a display area 12a and a peripheral area 12b are set on the substrate 12 of the display device 10. The display region 12a is configured as a pixel array section in which a plurality of scanning lines 21 and a plurality of signal lines 23 are wired vertically and horizontally, and one pixel a is provided corresponding to each intersection. In each of these pixels a, a red light emitting organic electroluminescent element (red light emitting element) 11R, a green light emitting organic electroluminescent element (green light emitting element) 11G, and a blue light emitting organic electroluminescent element (blue light emitting element). One of 11B is provided. In particular, the present embodiment is characterized in that the organic electroluminescent element 11 described above is used as the blue light emitting element 11B.

  In the peripheral region 12b, a scanning line driving circuit b that scans and drives the scanning lines 21, and a signal line driving circuit c that supplies a video signal (that is, an input signal) corresponding to luminance information to the signal line 23 are arranged. Yes.

  As shown in FIG. 2B, the pixel circuit provided in each pixel a includes, for example, one of the organic electroluminescent elements 11R, 11G, and 11B (11), a driving transistor Tr1, and a writing transistor (sampling transistor). It is composed of Tr2 and a holding capacitor Cs. Then, the video signal written from the signal line 23 via the write transistor Tr2 is held in the holding capacitor Cs by driving by the scanning line driving circuit b, and a current corresponding to the held signal amount is supplied to each organic electroluminescent element 11R. , 11G, 11B (11), and the organic electroluminescent elements 11R, 11G, 11B (11) emit light with a luminance corresponding to the current value.

  Note that the configuration of the pixel circuit as described above is merely an example, and a capacitor element may be provided in the pixel circuit as necessary, or a plurality of transistors may be provided to configure the pixel circuit. In addition, a necessary drive circuit is added to the peripheral region 2b according to the change of the pixel circuit.

<< Cross-sectional structure of display device >>
FIG. 3 shows an example of a cross-sectional configuration of the main part in the display area of the display device 10.

  In the display region of the substrate 12 on which the organic electroluminescent elements 11R, 11G, and 11B (11) are provided, although not shown here, a driving transistor, a writing transistor, a scanning line, And a signal line (see FIG. 2), and an insulating film is provided so as to cover them.

  On the substrate 12 covered with this insulating film, organic electroluminescent elements 11R, 11G, and 11B (11) are arrayed. Each of the organic electroluminescent elements 11R, 11G, and 11B (11) is configured as a top-emitting element that extracts light from the side opposite to the substrate 12.

  The anode 13 of each organic electroluminescent element 11R, 11G, 11B (11) is patterned for each element. Each anode 13 is connected to a drive transistor of the pixel circuit through a connection hole formed in an insulating film covering the surface of the substrate 12.

  Each anode 13 is covered with an insulating film 31 at its peripheral edge, and the central portion of the anode 13 is exposed at an opening provided in the insulating film 31. The organic layer 14 is patterned so as to cover the exposed portion of the anode 13, and the cathode 15 is provided as a common layer covering each organic layer 14.

  Among these organic electroluminescent elements 11R, 11G, and 11B (11), in particular, the blue light emitting element 11B is configured as the organic electroluminescent element (11) of the embodiment described with reference to FIG.

  That is, in the blue light emitting element 11B, the organic layer 14 provided on the anode 13 includes, for example, sequentially from the anode 13 side, a hole injection layer 14a, a hole transport layer 14b including a specific material and a blue light emitting dye, and a host material. A blue light emitting layer 14c-B (14c) using an anthracene derivative and an electron transport layer 14d are stacked.

  On the other hand, the organic layers in the red light emitting element 11R and the green light emitting element 11G are, for example, sequentially from the anode 13 side, a hole injection layer 14a, a hole transport layer 14b, a red light emitting layer 14c-R or a green light emitting layer 14c-G, and The electron transport layer 14d is laminated in this order. The light emitting layer 14c-B of the blue light emitting element 11B may be laminated on the light emitting layer 14c-R of the red light emitting element 11R and the light emitting layer 14c-G of the green light emitting element 11G.

  Further, the hole transport layer 14b in the red light emitting element 11R and the green light emitting element 11G may have the same configuration as the hole transport layer 14b in the blue light emitting element 11B. In addition, each layer other than the light emitting layers 14c-R, 14c-G, and 14c-B, including the anode 13 and the cathode 15, is composed of the same material in each of the organic electroluminescent elements 11R, 11G, and 11B. It is good and is comprised using each material demonstrated using FIG.

  The plurality of organic electroluminescent elements 11R, 11G, and 11B (11) provided as described above are covered with a protective film. The protective film is provided so as to cover the entire display area where the organic electroluminescent elements 11R, 11G, and 11B are provided.

  Here, each layer from the anode 13 to the cathode 15 constituting the red light emitting element 11R, the green light emitting element 11G, and the blue light emitting element 11B (11) is formed by a vacuum deposition method, an ion beam method (EB method), a molecular beam epitaxy method. (MBE method), sputtering method, Organic Vapor Phase Deposition (OVPD) method, and other dry processes.

  For the organic layer 14, in addition to the above methods, a laser transfer method, a spin coating method, a dipping method, a doctor blade method, a discharge coating method, a spray coating method, and other coating methods, an inkjet method, an offset printing method, a letterpress It can also be formed by wet processes such as printing methods, intaglio printing methods, screen printing methods, printing methods such as micro gravure coating methods, etc., depending on the properties of each organic layer and each member, using both dry and wet processes. It doesn't matter.

  The organic layer 14 patterned for each of the organic electroluminescent elements 11R, 11G, and 11B (11) as described above is formed by, for example, a vapor deposition method or a transfer method using a mask.

  In the display device 10 configured as described above, the organic electroluminescent element (11) having the configuration of the present invention described with reference to FIG. 1 is used as the blue light emitting element 11B. The blue light emitting element 11B (11) exhibits high current efficiency as described above. Therefore, by combining the blue light emitting element 11B (11) with the red light emitting element 11R and the green light emitting element 11G, full color display with high color expression can be performed.

  Further, the use of the organic electroluminescent element (11) having high luminous efficiency can improve the luminance life and reduce the power consumption in the display device 10. Therefore, it can be suitably used as a flat panel display such as a wall-mounted TV or a flat light emitter, and can be applied to a light source such as a copying machine or a printer, a light source such as a liquid crystal display or an instrument, a display board, a marker lamp, etc. It becomes.

  In the above example, the embodiment in which the present invention is applied to an active matrix display device has been described. However, the display device of the present invention can be applied to a passive matrix display device, and the same effect can be obtained.

  The display device according to the present invention described above includes a module-shaped one having a sealed configuration as disclosed in FIG. For example, a sealing part 31 is provided so as to surround the display area 12a which is a pixel array part on the substrate 12, and this sealing part 31 is attached to an opposing part (sealing substrate 32) such as transparent glass as an adhesive. The display module formed and formed corresponds to this. The transparent sealing substrate 32 may be provided with a color filter, a protective film, a light shielding film, and the like. The substrate 12 as a display module in which the display area 12a is formed may be provided with a flexible printed board 33 for inputting / outputting signals and the like from the outside to the display area 12a (pixel array portion).

≪Application example≫
The display device according to the present invention described above is input to various electronic devices shown in FIGS. 5 to 9 such as digital cameras, notebook personal computers, portable terminal devices such as mobile phones, and video cameras. The video signal generated or the video signal generated in the electronic device can be applied to a display device of an electronic device in any field for displaying as an image or a video. An example of an electronic device to which the present invention is applied will be described below.

  FIG. 5 is a perspective view showing a television to which the present invention is applied. The television according to this application example includes a video display screen unit 101 including a front panel 102, a filter glass 103, and the like, and is created by using the display device according to the present invention as the video display screen unit 101.

  6A and 6B are diagrams showing a digital camera to which the present invention is applied. FIG. 6A is a perspective view seen from the front side, and FIG. 6B is a perspective view seen from the back side. The digital camera according to this application example includes a light emitting unit 111 for flash, a display unit 112, a menu switch 113, a shutter button 114, and the like, and is manufactured by using the display device according to the present invention as the display unit 112.

  FIG. 7 is a perspective view showing a notebook personal computer to which the present invention is applied. A notebook personal computer according to this application example includes a main body 121 including a keyboard 122 that is operated when characters and the like are input, a display unit 123 that displays an image, and the like. It is produced by using.

  FIG. 8 is a perspective view showing a video camera to which the present invention is applied. The video camera according to this application example includes a main body 131, a lens 132 for shooting an object on a side facing forward, a start / stop switch 133 at the time of shooting, a display unit 134, and the like. It is manufactured by using such a display device.

  FIG. 9 is a diagram showing a portable terminal device to which the present invention is applied, for example, a cellular phone, in which (A) is a front view in an opened state, (B) is a side view thereof, and (C) is in a closed state. (D) is a left side view, (E) is a right side view, (F) is a top view, and (G) is a bottom view. The mobile phone according to this application example includes an upper housing 141, a lower housing 142, a connecting portion (here, a hinge portion) 143, a display 144, a sub display 145, a picture light 146, a camera 147, and the like. And the sub display 145 is manufactured by using the display device according to the present invention.

  The manufacturing procedure of the organic electroluminescent element of the specific Example of this invention and a comparative example is demonstrated with reference to FIG. 1, and these evaluation results are demonstrated next.

<Examples 1-6>
First, a substrate 12 made of a 30 mm × 30 mm glass plate is prepared, and an anode 13 in which an ITO transparent electrode with a film thickness of 12.5 nm is laminated on a 190 nm-thick Ag alloy (reflection layer) is formed. A cell for an organic electroluminescent element was prepared.

  Next, as a hole injection layer 14a of the organic layer 14, a film made of m-MTDATA represented by the following structural formula (101) is formed to a thickness of 8 nm (deposition rate: 0.2 to 0.4 nm / sec). However, m-MTDATA is 4,4 ′, 4 ″ -tris (phenyl-m-tolylamino) triphenylamine.

  Next, as a first layer of the hole transport layer 14b, a film made of α-NPD represented by the following structural formula (102) was formed with a film thickness of 12 nm (deposition rate: 0.2 to 0.4 nm / sec). . However, α-NPD is N, N′-bis (1-naphthyl) -N, N′-diphenyl [1,1′-biphenyl] -4,4′-diamine.

  Next, for each example, as the second layer of the hole transport layer 14b, a hole transport material represented by the following structural formulas (103) to (108) and an amino chrysene derivative represented by the structural formula (109) A film made of a blue luminescent dye was formed to a thickness of 10 nm. The vapor deposition rate was 0.2 to 0.4 nm / sec for the hole transport material, and the blue light emitting dye was 5% of the hole transport material. As a result, the blue luminescent dye was adjusted to a doping amount (relative film thickness ratio) of 5%. Example 1 is structural formula (103), Example 2 is structural formula (104), Example 3 is structural formula (105), Example 4 is structural formula (106), and Example 5 is structural formula (107). In Example 6, each hole transport material represented by the structural formula (108) was used.

  Next, a light-emitting layer 14c having a thickness of 28 nm was deposited on the hole transport layer 14b having a two-layer structure. At this time, 9,10-di (2-naphthyl) anthracene (ADN) represented by the following structural formula (110) is used as a host material, and the amino chrysene derivative represented by the above structural formula (109) is used for blue light emission. Was doped as a functional guest material (blue light emitting dye). The blue light emitting guest material was 5% doping amount (relative film thickness ratio).

  Next, as the electron transport layer 14d, Alq3 (8-hydroxyquinoline aluminum) represented by the following structural formula (111) was deposited with a thickness of 12 nm.

  As described above, after forming the organic layer 14 in which the hole injection layer 14a, the hole transport layer 14b having the stacked structure, the light emitting layer 14c, and the electron transport layer 14d are sequentially stacked, the first layer of the cathode 15 is formed. As a film 15a, a film made of LiF was formed with a film thickness of about 0.3 nm (deposition rate 0.01 nm / sec.) By a vacuum evaporation method. Finally, an MgAg film having a thickness of 9 nm was formed as the second layer 15b of the cathode 15 on the first layer 15a by vacuum deposition.

<Comparative Examples 1-6>
The formation of the second layer of the hole transport layer 14b in the procedure for manufacturing the organic electroluminescent elements described in Examples 1 to 6 was performed without using a blue light emitting dye. Except this, it carried out similarly to Examples 1-6.

<Comparative Example 7>
In the production procedure of the organic electroluminescent element described in Example 1, Example 1 except that α-NPD of the structural formula (102) was used as the hole transport material of the second layer of the hole transport layer 14b. As well as.

<Evaluation results>
About each organic electroluminescent element produced in the above Examples 1-6 and Comparative Examples 1-7, the drive voltage (V) at the time of a drive at a current density of 10 mA / cm < ² > at room temperature, current efficiency (cd / A) The color coordinates (x, y) were measured. In addition, the luminance half time was measured by driving at a constant current at a current density of 100 mA / cm ² at room temperature. The above results are shown in Table 4 below together with the material of the hole transport layer 14b in contact with the light emitting layer 14c.

  As shown in Table 4 above, in any of the organic electroluminescent elements of Examples 1 to 6 in which the present invention is applied and the hole-transporting layer 14b portion in contact with the light-emitting layer 14c includes a blue light-emitting dye, Compared with the organic electroluminescent elements of Comparative Examples 1 to 7 to which the present invention is not applied, the current efficiency is improved with the same driving voltage. Further, since the luminance life is also prolonged, it was found that a good organic electroluminescence device can be obtained by the present invention.

<Example 7>
A display device using an organic electroluminescent element similar to that of Example 1 was produced as follows (see FIG. 3).

  First, the anode 13 was patterned on the display area of the substrate 12 to form an insulating film 31 having an opening exposing the center of each anode 13. Next, a hole injection layer 14a and a hole transport layer 14b having a laminated structure were formed in the same procedure as in Example 1 using a large opening mask having openings corresponding to the entire display region.

  Next, a light emitting layer 14c-R for the red area was formed using a stripe mask having an opening corresponding to the formation area (red area) of the red light emitting element. Subsequently, a light emitting layer 14c-G in the green area was formed using a stripe mask provided with an opening corresponding to the formation area (green area) of the green light emitting element. Thereafter, a light emitting layer 14c-B in the blue area was formed in the same manner as in Example 1 using a stripe mask having an opening corresponding to the formation area (blue area) of the blue light emitting element. Finally, the electron transport layer 14e and the cathode 15 were formed in this order.

  Thus, a display device in which a red light emitting element was formed in the red area, a green light emitting element was formed in the green area, and a blue light emitting element was formed in the blue area was obtained.

<Examples 11 to 15>
A cell for an organic electroluminescence device for top emission similar to Examples 1 to 6 was produced.

  On top of this, a film made of m-MTDATA represented by the above structural formula (101) is formed as a hole injection layer 14a of the organic layer 14 by a vacuum deposition method to a thickness of 10 nm (deposition rate 0.2 to 0.4 nm). / Sec).

  Next, as the first layer of the hole transport layer 14b, a film made of α-NPD represented by the structural formula (102) was formed to a thickness of 10 nm (deposition rate: 0.2 to 0.4 nm / sec). .

  Next, for each example, as the second layer of the hole transport layer 14b, the hole transport material represented by the following structural formulas (112) to (116) and the aminochrysene represented by the above structural formula (109) are used. A film made of a blue luminescent dye of a derivative was formed with a thickness of 10 nm. The vapor deposition rate was 0.2 to 0.4 nm / sec for the hole transport material, and the blue light emitting dye was 5% of the hole transport material. As a result, the blue luminescent dye was adjusted to a doping amount (relative film thickness ratio) of 5%. Example 11 is structural formula (112), Example 12 is structural formula (113), Example 13 is structural formula (114), Example 14 is structural formula (115), and Example 15 is structural formula (116). ) Hole transport materials were used.

  Next, a light emitting layer 14c having a thickness of 30 nm was deposited on the hole transport layer 14b. At this time, 9,10-di (2-naphthyl) anthracene (ADN) having the above structural formula (110) was used as a host material, and the amino chrysene derivative represented by the above structural formula (109) was used as a blue light emitting material. Doped as guest material. The blue light emitting guest material was 5% doping amount (relative film thickness ratio).

  Next, Alq3 (8-hydroxyquinoline aluminum) represented by the above structural formula (111) was vapor-deposited with a thickness of 10 nm as the electron transport layer 14d.

  As described above, after forming the organic layer 14 in which the hole injection layer 14a, the hole transport layer 14b having the stacked structure, the light emitting layer 14c, and the electron transport layer 14d are sequentially stacked, the first layer of the cathode 15 is formed. As a film 15a, a film made of LiF was formed with a film thickness of about 0.5 nm (deposition rate 0.01 nm / sec.) By vacuum evaporation. Finally, an MgAg film having a thickness of 9 nm was formed as the second layer 15b of the cathode 15 on the first layer 15a by vacuum deposition.

<Comparative Examples 11-15>
Formation of the second layer of the hole transport layer 14b in the procedure for manufacturing the organic electroluminescent element described in Examples 11 to 15 was performed without using a blue light emitting dye. Except this, it carried out similarly to Examples 11-15.

<Comparative Example 16>
In the production procedure of the organic electroluminescent element described in Example 11, Example 11 was used except that α-NPD of the structural formula (102) was used as the hole transport material of the second layer of the hole transport layer 14b. As well as.

<Evaluation results>
About each organic electroluminescent element produced in the above Examples 11-15 and Comparative Examples 11-16, the drive voltage (V) at the time of a drive at a current density of 10 mA / cm < ² > at room temperature, current efficiency (cd / A) The color coordinates (x, y) were measured. In addition, the luminance half time was measured by driving at a constant current at a current density of 100 mA / cm ² at room temperature. The above results are shown in Table 5 below together with the material of the hole transport layer 14b in contact with the light emitting layer 14c.

  As shown in Table 5 above, in any of the organic electroluminescent elements of Examples 11 to 15 in which the present invention is applied and a blue light-emitting dye is included in the hole transport layer 14b portion in contact with the light-emitting layer 14c, Compared with the organic electroluminescent elements of Comparative Examples 11 to 14 to which the present invention is not applied, the current efficiency is improved with the same driving voltage. Further, since the luminance life is also prolonged, it was found that a good organic electroluminescence device can be obtained by the present invention.

<Example 16>
A display device similar to that of Example 7 described above is manufactured using the same organic electroluminescent element as that of Example 11. The red light emitting element is formed in the red area, the green light emitting element is formed in the green area, and blue. A display device having a blue light emitting element formed in the area was obtained.

It is a cross-sectional block diagram explaining the organic electroluminescent element of embodiment. It is a figure which shows an example of the circuit structure of the display apparatus of embodiment. An example of the cross-sectional structure of the principal part in the display apparatus of embodiment is shown. It is a block diagram which shows the module-shaped display apparatus of the sealed structure to which this invention is applied. It is a perspective view which shows the television to which this invention is applied. It is a figure which shows the digital camera to which this invention is applied, (A) is the perspective view seen from the front side, (B) is the perspective view seen from the back side. 1 is a perspective view showing a notebook personal computer to which the present invention is applied. It is a perspective view which shows the video camera to which this invention is applied. BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the portable terminal device to which this invention is applied, for example, a mobile telephone, (A) is the front view in the open state, (B) is the side view, (C) is the front view in the closed state , (D) is a left side view, (E) is a right side view, (F) is a top view, and (G) is a bottom view.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Display apparatus, 11 ... Organic electroluminescent element, 11B ... Blue light emitting element, 12 ... Substrate, 13 ... Anode, 14 ... Organic layer, 14b ... Hole transport layer, 14c ... Light emitting layer, 15 ... Cathode

Claims (7)

In a blue light emitting organic electroluminescent element formed by sandwiching an organic layer in which at least a hole transport layer and a light emitting layer are laminated in this order from the anode side between the anode and the cathode,
The light emitting layer includes a host material and a blue light emitting dye,
The hole transport layer is provided adjacent to the light-emitting layer, and includes a compound represented by the following general formula (1) or general formula (2) and a blue light-emitting dye. .

However, in the general formula (1),
Ar ¹ and Ar ² each independently represent an aromatic hydrocarbon ring group or an aromatic heterocyclic group,
R ^{1 to} R ⁸ are each independently a hydrogen atom, halogen atom, alkyl group, aralkyl group, alkenyl group, cyano group, amino group, acyl group, alkoxycarbonyl group, carboxyl group, alkoxy group, aryloxy group, An alkylsulfonyl group, a hydroxyl group, an amide group, an aromatic hydrocarbon ring group, or an aromatic heterocyclic group, and adjacent ones of R ^{1 to} R ⁸ may form a ring;
X represents a linking group formed by bonding 1 to 4 divalent aromatic groups.
In the general formula (2),
X ¹ represents an N-carbazoyl group, an N-phenoxadiyl group, or an N-phenothiadiyl group,
X ² represents an N-carbazoyl group, an N-phenoxadiyl group, an N-phenothiadiyl group, or —NAR ³ AR ⁴ (AR ³ and AR ⁴ are heterocyclic aromatic groups);
B ¹ and B ² each independently represent a hydrogen atom, an alkyl group, a carbocyclic aromatic group, a heterocyclic aromatic group, or an aralkyl group,
Z ¹ and Z ² each independently represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a carbocyclic aromatic group, or a heterocyclic aromatic group. In the organic electroluminescent device according to claim 1,
The hole transport layer is composed of a plurality of layers, and the hole transport layer in contact with the light emitting layer contains the compound represented by the general formula (1) or the general formula (2) and a blue light emitting dye. Electroluminescent device. The organic electroluminescent device according to claim 1, wherein
The blue electroluminescent element in the said positive hole transport layer is the same as the blue electroluminescent dye in the said light emitting layer. The organic electroluminescent element characterized by the above-mentioned. The organic electroluminescent device according to claim 1, wherein
A compound represented by the following general formula (3) is used as a host material for the light emitting layer.

However, in the general formula (3), R ^{11 to} R ¹⁶ are independently hydrogen, halogen, hydroxyl group, carbonyl group, carbonyl ester group, alkyl group, alkenyl group, alkoxyl group, cyano group, nitro group, silyl group. A group, an aryl group, a heterocyclic group, and an amino group; The organic electroluminescent device according to claim 1, wherein
A compound represented by the following general formula (4) is used as the blue light-emitting dye.

However, in general formula (4),
R ^{21 to} R ³⁰ each independently represent a hydrogen atom, an alkyl group, an aryl group, or a cyano group,
A _{1 to} A ₄ each independently represents a hydrogen atom, an alkyl group, an aryl group, an alkoxyl group, an aryloxy group, an arylamino group, an alkylamino group, or a halogen atom;
M in A _{1 to} A ₄ each independently represents an integer of 0 to 5, and when m is 2 or more, A _{1 to} A ₄ may be the same or different, and may be connected to each other to be saturated or unsaturated. May form a saturated ring,
A ₁ and A ₂ , A ₃ and A ₄ may be connected to each other to form a saturated or unsaturated ring, but it does not include the case where all of A _{1 to} A ₄ are hydrogen atoms. The organic electroluminescent device according to claim 1, wherein
The organic electroluminescence device, wherein emitted light generated in the light emitting layer is extracted from one side of the anode or cathode due to multiple interference between any layers between the anode and the cathode. 2. A display device comprising the organic electroluminescent element according to claim 1 as a blue light-emitting element in a part of a plurality of pixels.

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