JPWO2015005440A1 - Material for light emitting auxiliary layer containing ring condensed fluorene compound or fluorene compound - Google Patents

Abstract

For example, an object of the present invention is to provide an organic EL element that efficiently uses the TTF phenomenon to increase the light emission efficiency. For example, a light emission auxiliary layer is provided between the light emitting layer and the electron transport layer in the organic electroluminescence device, and this light emission auxiliary layer is formed by 1 to 3 benzene rings in one of two benzene rings of fluorene. Provided is an organic EL device which is formed of a condensed ring-condensed fluorene compound and / or a fluorene compound, for example, a benzofluorene compound or a fluorene compound represented by the following formulas (1) to (3), and which has improved luminous efficiency. Wherein R 1 and R 2 are optionally substituted aryl or optionally substituted phenyl or fused ring system aryl, and R 3 and R 4 are optionally substituted alkyl or And aryl which may be substituted.)

Description

  The present invention relates to a material for a light-emitting auxiliary layer containing a ring-condensed fluorene compound and / or a fluorene compound, in particular, a benzofluorene compound, a dibenzofluorene compound, an indenotriphenylene compound, an indenopyrene compound and / or a fluorene compound, and an organic electric field using the same The present invention relates to a light emitting element, a display device, and the like.

  An organic electroluminescent element (hereinafter, also referred to as “organic EL element”) is a self-luminous light emitting element, and is expected as a light emitting element for display or illumination. Conventionally, display devices using light emitting elements that emit electroluminescence have been studied variously because they can save power and can be thinned. Furthermore, organic EL elements made of organic materials can be easily reduced in weight and size. Has been actively studied since. In particular, the development of organic materials with light emission characteristics such as blue, which is one of the three primary colors of light, and organic materials that have charge transporting ability (such as semiconductors and superconductors) such as holes and electrons The development of materials has been actively studied so far, regardless of whether it is a high molecular compound or a low molecular compound.

  The organic EL element has a structure including a pair of electrodes composed of an anode and a cathode and a light emitting layer formed between the pair of electrodes and formed of an organic compound. When organic EL elements are classified according to their light emission principles, they can be divided into two types, fluorescent and phosphorescent types. When a voltage is applied to the organic EL element, holes are injected from the anode and electrons are injected from the cathode, and these recombine in the light emitting layer to form excitons. According to the statistical rule of electron spin, singlet excitons and triplet excitons are generated at a ratio of 25%: 75%. Since the fluorescence type uses light emission from singlet excitons, the internal quantum efficiency was said to be 25%.

  However, several techniques for extracting light from triplet excitons that have not been effectively used so far have been disclosed in relation to techniques for improving the efficiency of fluorescent elements. For example, in Patent Document 1, in a normal organic molecule, the lowest triplet excited state (T1) is lower than the lowest singlet excited state (S1), but the higher triplet excited state (T2) may be higher than S1. In such a case, it is said that the light emission from the singlet excited state can be obtained by the transition from T2 to S1. In Non-Patent Document 1, a non-doped device using an anthracene compound as a host material is analyzed, and singlet excitons are generated by collision fusion of two triplet excitons, resulting in an increase in fluorescence emission. doing. In particular, a phenomenon in which singlet excitons are generated by collisional fusion of these two triplet excitons is called a TTF phenomenon (triplet-triplet fusion).

  Further, Patent Document 2 discusses increasing the efficiency of a fluorescent element by efficiently causing this TTF phenomenon. Specifically, there is a specific relationship between the triplet energy of the host material that can be used in the fluorescent element and the fluorescent light-emitting dopant material, and a barrier formed of a material having a high triplet energy at the cathode-side interface of the light-emitting layer. In the case where the layer is provided, triplet excitons are confined in the light emitting layer, and the TTF phenomenon is efficiently caused to achieve high efficiency and a long lifetime of the fluorescent element.

  In Patent Document 2, as a material used for the barrier layer, a hydrocarbon aromatic compound (Claim 4), for example, naphthalene, phenanthrene, chrysene, fluoranthene, triphenylene derivatives (paragraphs [0073] to [0094]) are described. Specifically, the EL characteristics of fluoranthene compounds and benzochrysene compounds ([Chemical Formula 34]) have been studied.

  Patent Document 3 describes that an organic EL device is produced using a benzofluorene-based compound substituted with an aryl group or an amino group. The relationship with the TTF phenomenon and triplet energy are described. Is not mentioned, and EL characteristics when this benzofluorene compound is used as a material for the light emitting layer are only confirmed.

  Further, a dibenzofluorene compound is used as a light emitting layer material (Patent Document 4), an indenotriphenylene compound is used as a light emitting layer material (Patent Documents 5 and 6), and an indenopyrene compound is used in an organic EL device. Examples used as materials for each layer are known (Patent Document 7 and Patent Document 8).

JP 2004-214180 A International Publication No. 2010/134350 JP 2008-291006 A International Publication No. 2011/0881403 Chinese Patent Application Publication No. 103508835 International Publication 2012/086366 JP 2011-077982 A International Publication No. 2010/053210

Journal of Applied Physics, 102, 114504 (2007)

  Under such circumstances, it is desired to develop an organic EL element that can efficiently use the TTF phenomenon, that is, a compound that can obtain the element.

  As a result of intensive studies to solve the above problems, the present inventor has found that a light emission auxiliary layer provided between a light emitting layer and an electron transport layer in an organic EL device is a ring condensed fluorene compound and / or a fluorene compound, particularly a certain specific An organic EL device which can efficiently use the TTF phenomenon by improving the internal quantum efficiency and the external quantum efficiency by forming with a benzofluorene compound, a dibenzofluorene compound, an indenotriphenylene compound, an indenopyrene compound and / or a fluorene compound. It was found that it can be obtained.

[1]
A light-emitting auxiliary layer material used for a light-emitting auxiliary layer between a light-emitting layer and an electron transport layer in an organic electroluminescence device, wherein 1 to 3 benzene rings are present in any one of two benzene rings of fluorene Is a material for a light-emitting auxiliary layer containing a ring-fused fluorene compound and / or a fluorene compound condensed with
The ring-fused fluorene compound and the five-membered ring of the fluorene compound may be substituted with an optionally substituted alkyl and / or an optionally substituted aryl, and two substituents are substituted on the five-membered ring. In some cases, these substituents may combine to form a ring,
At least a part of the benzene ring and / or the condensation site of the ring-fused fluorene compound is substituted with an optionally substituted aryl, and further an optionally substituted alkyl and / or an optionally substituted cycloalkyl. May be substituted, and
At least a part of the benzene ring of the fluorene compound is substituted with an optionally substituted phenyl or condensed ring system aryl, and further substituted with an optionally substituted alkyl and / or an optionally substituted cycloalkyl. And when the substituent on the phenyl or fused ring aryl is aryl, the aryl is phenyl or fused ring aryl.
Light emitting auxiliary layer material.

[2]
The light emitting auxiliary layer material is a light emitting auxiliary layer material containing a benzofluorene compound, a dibenzofluorene compound, an indenotriphenylene compound, an indenopyrene compound and / or a fluorene compound,
The five-membered ring of the benzofluorene compound, dibenzofluorene compound, indenotriphenylene compound, indenopyrene compound and fluorene compound may be substituted with an optionally substituted alkyl and / or an optionally substituted aryl, When two substituents are substituted on the five-membered ring, these substituents may be bonded to form a ring,
At least a part of the benzene ring and / or the condensation site of the benzofluorene compound, dibenzofluorene compound, indenotriphenylene compound and indenopyrene compound is substituted with an optionally substituted aryl, and an optionally substituted alkyl and And / or optionally substituted cycloalkyl, and
At least a part of the benzene ring of the fluorene compound is substituted with an optionally substituted phenyl or condensed ring system aryl, and further substituted with an optionally substituted alkyl and / or an optionally substituted cycloalkyl. And when the substituent on the phenyl or fused ring aryl is aryl, the aryl is phenyl or fused ring aryl.
The light emitting auxiliary layer material according to the above [1].

（上記式（２）〜（７）におけるＲ^１およびＲ^２は、それぞれ独立して、水素、置換されていてもよいアルキル、置換されていてもよいシクロアルキルまたは置換されていてもよいアリールであり、Ｒ^１およびＲ^２のうちの少なくとも１つは置換されていてもよいアリールであり、
上記式（１）におけるＲ^１およびＲ^２は、それぞれ独立して、水素、置換されていてもよいアルキル、置換されていてもよいシクロアルキル、または、置換されていてもよいフェニルもしくは縮合環系アリールであり、Ｒ^１およびＲ^２のうちの少なくとも１つは置換されていてもよいフェニルもしくは縮合環系アリールであり、前記フェニルもしくは縮合環系アリールへの置換基がアリールの場合には該アリールはフェニルもしくは縮合環系アリールであり、そして、
上記式（１）〜（７）におけるＲ^３およびＲ^４は、それぞれ独立して、置換されていてもよいアルキルまたは置換されていてもよいアリールであり、Ｒ^３およびＲ^４は結合して環を形成していてもよい。）[3]
The fluorene compound is represented by the following general formula (1), the benzofluorene compound is represented by the following general formula (2) or the following general formula (3), and the dibenzofluorene compound is represented by the following general formula (4). The indenotriphenylene compound is represented by the following general formula (5) or the following general formula (6), and the indenopyrene compound is represented by the following general formula (7). material.

(R ¹ and R ² in the above formulas (2) to (7) are each independently hydrogen, optionally substituted alkyl, optionally substituted cycloalkyl, or optionally substituted aryl. And at least one of R ¹ and R ² is an optionally substituted aryl,
R ¹ and R ² in the above formula (1) are each independently hydrogen, optionally substituted alkyl, optionally substituted cycloalkyl, or optionally substituted phenyl or fused ring system. Is aryl, and at least one of R ¹ and R ² is an optionally substituted phenyl or fused ring aryl, and when the substituent on the phenyl or fused ring aryl is an aryl, the aryl Is phenyl or fused ring aryl, and
R ³ and R ⁴ in the above formulas (1) to (7) are each independently an optionally substituted alkyl or an optionally substituted aryl, and R ³ and R ⁴ are bonded to form a ring. May be formed. )

[4]
R ¹ and R ² in the above formulas (2) to (7) are each independently hydrogen, optionally substituted alkyl having 1 to 24 carbon atoms, or optionally substituted 3 to 12 carbon atoms. Cycloalkyl or optionally substituted aryl having 6 to 30 carbon atoms, and at least one of R ¹ and R ² is optionally substituted aryl having 6 to 30 carbon atoms;
R ¹ and R ² in formula (1) are each independently hydrogen, optionally substituted alkyl having 1 to 24 carbon atoms, optionally substituted cycloalkyl having 3 to 12 carbon atoms, or An optionally substituted phenyl having 6 to 30 carbon atoms or a condensed ring aryl, and at least one of R ¹ and R ² may be optionally substituted phenyl having 6 to 30 carbon atoms or a condensed ring. System aryl,
R ³ and R ⁴ in the above formulas (1) to (7) are each independently an optionally substituted alkyl having 1 to 24 carbon atoms or an optionally substituted aryl having 6 to 30 carbon atoms. Each of R ³ and R ⁴ may be combined to form a ring;
The substituents in R ¹ and R ² in the above formulas (2) to (7) are each independently alkyl having 1 to 24 carbon atoms, cycloalkyl having 3 to 12 carbon atoms, or aryl having 6 to 30 carbon atoms. is there,
The substituents in R ¹ and R ² of the above formula (1) are each independently alkyl having 1 to 24 carbon atoms, cycloalkyl having 3 to 12 carbon atoms, phenyl having 6 to 30 carbon atoms, or fused ring aryl. And
The substituents in R ³ and R ⁴ in the above formulas (1) to (7) are each independently alkyl having 1 to 24 carbon atoms, cycloalkyl having 3 to 12 carbon atoms, or aryl having 6 to 30 carbon atoms. is there,
The light emitting auxiliary layer material described in [3] above.

[5]
R ¹ and R ² in the above formulas (2) to (7) are optionally substituted aryl having 6 to 24 carbon atoms,
R ¹ and R ² in the above formula (1) are optionally substituted phenyl having 6 to 24 carbon atoms or condensed ring aryl,
R ³ and R ⁴ in the above formulas (1) to (7) are each independently an optionally substituted alkyl having 1 to 12 carbon atoms or an optionally substituted aryl having 6 to 16 carbon atoms. Yes, when R ³ and R ⁴ are aryl, the aryls may be bonded to form a ring,
The substituents in R ¹ and R ² in the above formulas (2) to (7) are each independently alkyl having 1 to 12 carbons, cycloalkyl having 3 to 6 carbons or aryl having 6 to 20 carbons. Yes,
The substituents in R ¹ and R ² of the above formula (1) are each independently alkyl having 1 to 12 carbons, cycloalkyl having 3 to 6 carbons, phenyl having 6 to 20 carbons, or a condensed ring aryl. And
The substituents in R ³ and R ⁴ in the above formulas (1) to (7) are each independently alkyl having 1 to 12 carbons, cycloalkyl having 3 to 6 carbons or aryl having 6 to 20 carbons. is there,
The light emitting auxiliary layer material described in [3] above.

[6]
A benzofluorene compound represented by the general formula (2) or the general formula (3),
R ¹ and R ² are optionally substituted aryl having 6 to 20 carbon atoms,
R ³ and R ⁴ are each independently an optionally substituted alkyl having 1 to 6 carbon atoms or an optionally substituted aryl having 6 to 12 carbon atoms, wherein R ³ and R ⁴ are aryl The aryls may be joined together to form a ring, and
The substituents in R ¹ , R ² , R ³ and R ⁴ are each independently methyl, ethyl, propyl, t-butyl, cyclobutyl, cyclopentyl, cyclohexyl, phenyl, biphenylyl or naphthyl.
The light emitting auxiliary layer material described in [3] above.

[7]
A benzofluorene compound represented by the general formula (2) or the general formula (3),
R ¹ and R ² are each independently phenyl, biphenylyl, terphenylyl, quaterphenylyl, naphthyl or phenanthryl; and
R ³ and R ⁴ are each independently methyl, ethyl, propyl, t-butyl, phenyl or biphenylyl, phenyl or biphenylyl may be bonded to each other to form a ring,
The light emitting auxiliary layer material described in [3] above.

[8]
It is described in the above [3] represented by any one of the following formula (2-1), formula (2-2), formula (2-3), formula (2-4) and formula (2-5). Light emitting auxiliary layer material.

[9] The following formula (1-1), formula (1-71), formula (2-21), formula (2-41), formula (2-61), formula (2-62), formula (2- 85), formula (2-87), formula (3-5), formula (3-6), formula (3-8), formula (5-7) and formula (6-9). The material for light emission auxiliary layer described in [3] above.

[10]
A pair of electrodes composed of an anode and a cathode; a light emitting layer disposed between the pair of electrodes; an electron transport layer disposed between the cathode and the light emitting layer; the light emitting layer and the electron transport layer; An organic electroluminescence device having a light emission auxiliary layer disposed between
The light emitting auxiliary layer is an organic electroluminescent element formed of the light emitting auxiliary layer material described in any one of [1] to [9].

[11]
The light emitting layer is composed of a host material and a fluorescent light emitting dopant material having an emission wavelength having a peak at 400 to 500 nm,
The triplet energy E ^T _{h of the} host material is smaller than the triplet energy E ^T _{a of the} light emitting auxiliary layer material,
Organic electroluminescent element as described in said [10].

[12]
The light emitting layer is composed of a host material and a fluorescent light emitting dopant material having an emission wavelength having a peak at 400 to 500 nm,
The triplet energy E ^T _{d of the} dopant material is greater than the triplet energy E ^T _{h of the} host material,
Organic electroluminescent element as described in said [10] or [11].

[13]
The light emitting layer is composed of a host material and a fluorescent light emitting dopant material having an emission wavelength having a peak at 400 to 500 nm,
The host material contains at least one selected from the group consisting of anthracene derivatives and pyrene derivatives,
The dopant material contains at least one selected from the group consisting of an amine-containing benzofluorene derivative, an amine-containing pyrene derivative, an amine-free pyrene derivative, an amine-containing chrysene derivative, and an amine-containing styryl derivative.
The organic electroluminescent element according to any one of [10] to [12].

[14]
The organic electroluminescent element according to any one of [10] to [13], wherein the electron transport layer material contains a heterocyclic ring-containing compound.

[15]
The organic electroluminescence according to [14] above, wherein the heterocyclic ring-containing compound is at least one selected from the group consisting of pyridine derivatives, thiazole derivatives, benzothiazole derivatives, benzimidazole derivatives, phenanthroline derivatives, and phosphine oxide derivatives. element.

[16]
The relationship between the affinity A _a of the light emission auxiliary layer material and the affinity A _e of the electron transport layer material forming the electron transport layer is A _a > A _e −0.8 eV,
The organic electroluminescent element according to any one of [10] to [15].

[17]
A display device comprising the organic electroluminescent element according to any one of [10] to [16].

[18]
The illuminating device provided with the organic electroluminescent element as described in any one of said [10] thru | or [16].

  According to a preferred aspect of the present invention, it is possible to provide an organic EL device that can efficiently use the TTF phenomenon generated in the light emitting layer and improve the external quantum efficiency. Moreover, since the applied charge can be efficiently used by improving the external quantum efficiency, it is possible to provide an organic EL element that suppresses deterioration of the organic EL element and further improves the element lifetime.

It is a schematic sectional drawing which shows the organic EL element which concerns on this embodiment.

1. Organic Electroluminescent Device An organic EL device using the light emitting auxiliary layer material according to the present invention will be described in detail based on the drawings. FIG. 1 is a schematic cross-sectional view showing an organic EL element according to this embodiment.

<Structure of organic EL element>
An organic EL element 100 shown in FIG. 1 includes a substrate 101, an anode 102 provided on the substrate 101, a hole injection layer 103 provided on the anode 102, and a hole injection layer 103. Provided on the provided hole transport layer 104, the light emitting layer 105 provided on the hole transport layer 104, the light emitting auxiliary layer 110 provided on the light emitting layer 105, and the light emitting auxiliary layer 110. The electron transport layer 106, the electron injection layer 107 provided on the electron transport layer 106, and the cathode 108 provided on the electron injection layer 107.

  The organic EL element 100 is manufactured in the reverse order, for example, the substrate 101, the cathode 108 provided on the substrate 101, the electron injection layer 107 provided on the cathode 108, and the electron injection layer 107. The electron transport layer 106 provided on the light emitting layer, the light emitting auxiliary layer 110 provided on the electron transport layer 106, the light emitting layer 105 provided on the light emitting auxiliary layer 110, and the light emitting layer 105 are provided. The positive hole transport layer 104, the positive hole injection layer 103 provided on the positive hole transport layer 104, and the anode 102 provided on the positive hole injection layer 103 may be used.

  Not all of the above-described layers are necessary. The minimum structural unit is composed of the anode 102, the light emitting layer 105, the light emission auxiliary layer 110, the electron transport layer 106, and the cathode 108, and the hole injection layer 103, the hole transport. The layer 104 and the electron injection layer 107 are arbitrarily provided. Moreover, each said layer may consist of a single layer, respectively, and may consist of multiple layers.

  As an aspect of the layer constituting the organic EL element, the constitutional aspect of “substrate / anode / hole injection layer / hole transport layer / light emitting layer / light emission auxiliary layer / electron transport layer / electron injection layer / cathode” described above is used. In addition, “substrate / anode / hole transport layer / light emitting layer / light emission auxiliary layer / electron transport layer / electron injection layer / cathode”, “substrate / anode / hole injection layer / light emission layer / light emission auxiliary layer / electron transport” Layer / electron injection layer / cathode ”,“ substrate / anode / hole injection layer / hole transport layer / light emitting layer / light emission auxiliary layer / electron transport layer / cathode ”,“ substrate / anode / light emission layer / light emission auxiliary layer / “Electron transport layer / electron injection layer / cathode”, “substrate / anode / hole transport layer / light emitting layer / light emission auxiliary layer / electron transport layer / cathode”, “substrate / anode / hole injection layer / light emission layer / light emission assist” Layer / electron transport layer / cathode ”and“ substrate / anode / light emitting layer / light emission auxiliary layer / electron transport layer / cathode ”may be employed.

2. Light emission auxiliary layer The role of the light emission auxiliary layer is to first suppress or prevent triplet excitons generated in the light emitting layer from diffusing into the electron transport layer (contain triplet excitons in the light emitting layer) to emit light. It is to generate the TTF phenomenon efficiently in the layer. The next role of the light emission auxiliary layer is to efficiently inject electrons from the cathode to the light emitting layer. This role is originally assumed by the electron transport layer (and the electron injection layer). However, since the light emission auxiliary layer is disposed between the light emitting layer and the electron transport layer, electron injection from the electron transport layer to the light emitting layer is performed. It is preferable not to greatly reduce or inhibit the properties.

<Light emitting auxiliary layer material>
The material for the light emission auxiliary layer according to the present invention is a ring-condensed fluorene compound (a compound in which 1 to 3 benzene rings are condensed with any one of 2 benzene rings) and / or a fluorene compound, in particular. Specific benzofluorene compounds, dibenzofluorene compounds, indenotriphenylene compounds, indenopyrene compounds and / or fluorene compounds,
This ring-fused fluorene compound and / or fluorene compound, in particular, benzofluorene compound, dibenzofluorene compound, indenotriphenylene compound, indenopyrene compound and fluorene compound,
The 5-membered ring may be substituted with an optionally substituted alkyl and / or an optionally substituted aryl, and when two substituents are substituted on the 5-membered ring, these substituents are bonded. To form a ring,
At least a part of the benzene ring (one of the two benzene rings of the fluorene in which the benzene ring is not condensed) and / or the condensation site of the ring-fused fluorene compound is substituted with an optionally substituted aryl, May be further substituted with an optionally substituted alkyl and / or an optionally substituted cycloalkyl, and
At least a part of the benzene ring (either one or both of the two benzene rings of fluorene) of the fluorene compound is substituted with an optionally substituted phenyl or a condensed ring system aryl, and further substituted. Optionally substituted with alkyl and / or optionally substituted cycloalkyl, and when the substituent to said phenyl or fused ring system aryl is aryl, said aryl is phenyl or fused ring system aryl .

The ring-fused fluorene compound is a compound in which 1 to 3 benzene rings are condensed to any one of the two benzene rings of fluorene. Further, the number of benzene rings condensed to any one of the two benzene rings of fluorene may be 1 to 3, but is preferably 1 or 2, more preferably 1. “Condensed” includes, in addition to a form directly condensed to a fluorene skeleton as illustrated below as an example, a form further condensed to a benzene ring directly condensed to fluorene. The “condensation site” means an aggregate part of a ring containing a fluorene-derived benzene ring, which is formed by condensation on a fluorene skeleton as illustrated below as an example. Of the ring-condensed fluorene compounds, a compound in which one benzene ring is condensed to one benzene ring in fluorene, that is, a benzofluorene compound is most preferable.

  As described above, the ring-condensed fluorene compound and the fluorene compound, particularly the benzofluorene compound, the dibenzofluorene compound, the indenotriphenylene compound, the indenopyrene compound and the fluorene compound, which can be used as the material for the light emitting auxiliary layer, The membered ring, the benzene ring belonging to the fluorene skeleton, and the condensation site formed by the condensation of the benzene ring to the fluorene skeleton can be substituted with various substituents. These substituents are represented by the following general formulas (1) to (3 ) And those described in formulas (4) to (7). In addition, the number of substituents to the benzene ring and the condensation site, the combination of substituents, or the substitution position cannot prevent triplet exciton diffusion to the electron transport layer at all, or the electron transport layer to the light emitting layer. There is no particular limitation as long as there is no significant hindrance to electron injection.

As the benzofluorene compound and the fluorene compound that can be used as the light emitting auxiliary layer material, those represented by the following general formulas (1) to (3) are particularly preferable.

As the dibenzofluorene compound, indenotriphenylene compound and indenopyrene compound that can be used as the material for the light emitting auxiliary layer, those represented by the following general formulas (4) to (7) are particularly preferable.

In general formula (1),
R ¹ and R ² are each independently hydrogen, optionally substituted alkyl, optionally substituted cycloalkyl, or optionally substituted phenyl or fused ring system aryl, and R ¹ And at least one of R ² is an optionally substituted phenyl or fused ring system aryl, and
R ³ and R ⁴ are each independently an optionally substituted alkyl or an optionally substituted aryl, and R ³ and R ⁴ may be bonded to form a ring.

In general formulas (2) to (7),
R ¹ and R ² are each independently hydrogen, optionally substituted alkyl, optionally substituted cycloalkyl, or optionally substituted aryl, and at least one of R ¹ and R ² One is an optionally substituted aryl, and
R ³ and R ⁴ are each independently an optionally substituted alkyl or an optionally substituted aryl, and R ³ and R ⁴ may be bonded to form a ring.

The “phenyl or fused ring aryl” of “optionally substituted phenyl or fused ring aryl” in R ¹ and R ² of the general formula (1) is, for example, a phenyl or fused ring having 6 to 30 carbon atoms. The system aryl is mentioned. The “phenyl or fused ring aryl” of R ¹ and R ² is preferably a phenyl or fused ring aryl having 6 to 24 carbon atoms, more preferably a phenyl or fused ring aryl having 6 to 20 carbon atoms, still more preferably Is phenyl having 6 to 12 carbon atoms or condensed ring aryl.

Examples of “aryl” of “optionally substituted aryl” in R ¹ and R ² of the general formulas (2) to (7) include aryl having 6 to 30 carbon atoms. The “aryl” of R ¹ and R ² is preferably aryl having 6 to 24 carbon atoms, more preferably aryl having 6 to 20 carbon atoms, and still more preferably aryl having 6 to 12 carbon atoms.

Examples of “aryl” of “optionally substituted aryl” in R ³ and R ⁴ of the general formulas (1) to (7) include aryl having 6 to 30 carbon atoms. The “aryl” of R ³ and R ⁴ is preferably aryl having 6 to 16 carbon atoms, more preferably aryl having 6 to 12 carbon atoms.

Specific “fused ring aryl” for R ¹ and R ^{2 in} the general formula (1) includes (1-, 2-) naphthyl which is a fused bicyclic aryl, and acenaphthylene which is a fused tricyclic aryl. -(1-, 3-, 4-, 5-) yl, fluorene- (1-, 2-, 3-, 4-, 9-) yl, phenalen- (1-, 2-) yl, (1- , 2-, 3-, 4-, 9-) phenanthryl, condensed tetracyclic aryl triphenylene- (1-, 2-) yl, pyrene- (1-, 2-, 4-) yl, naphthacene- ( 1-, 2-, 5-) yl, fused pentacyclic aryl perylene- (1-, 2-, 3-) yl, pentacene- (1-, 2-, 5-, 6-) yl and the like can give.

Specific examples of “aryl” for R ¹ and R ^{2 in the} general formulas (2) to (7) include monocyclic aryl phenyl and bicyclic aryl (2-, 3-, 4-). Biphenylyl, condensed bicyclic aryl (1-, 2-) naphthyl, tricyclic aryl terphenylyl (m-terphenyl-2'-yl, m-terphenyl-4'-yl, m-terphenyl) -5'-yl, o-terphenyl-3'-yl, o-terphenyl-4'-yl, p-terphenyl-2'-yl, m-terphenyl-2-yl, m-terphenyl- 3-yl, m-terphenyl-4-yl, o-terphenyl-2-yl, o-terphenyl-3-yl, o-terphenyl-4-yl, p-terphenyl-2-yl, p -Terphenyl-3-yl, p-terphenyl-4-yl Acenaphthylene- (1-, 3-, 4-, 5-) yl, fluorene- (1-, 2-, 3-, 4-, 9-) yl, phenalene- (1 -, 2-) yl, (1-, 2-, 3-, 4-, 9-) phenanthryl, quaterphenylyl which is a tetracyclic aryl (5'-phenyl-m-terphenyl-2-yl, 5′-phenyl-m-terphenyl-3-yl, 5′-phenyl-m-terphenyl-4-yl, m-quaterphenyl), triphenylene- (1-, 2- ) Yl, pyrene- (1-, 2-, 4-) yl, naphthacene- (1-, 2-, 5-) yl, perylene- (1-, 2-, 3-) which is a fused pentacyclic aryl Yl, pentacene- (1-, 2-, 5-, 6-) yl and the like.

Specific examples of “aryl” for R ³ and R ^{4 in the} general formulas (1) to (7) include monocyclic aryl phenyl and bicyclic aryl (2-, 3-, 4-). Biphenylyl, condensed bicyclic aryl (1-, 2-) naphthyl, tricyclic aryl terphenylyl (m-terphenyl-2'-yl, m-terphenyl-4'-yl, m-terphenyl) -5'-yl, o-terphenyl-3'-yl, o-terphenyl-4'-yl, p-terphenyl-2'-yl, m-terphenyl-2-yl, m-terphenyl- 3-yl, m-terphenyl-4-yl, o-terphenyl-2-yl, o-terphenyl-3-yl, o-terphenyl-4-yl, p-terphenyl-2-yl, p -Terphenyl-3-yl, p-terphenyl-4-yl Acenaphthylene- (1-, 3-, 4-, 5-) yl, fluorene- (1-, 2-, 3-, 4-, 9-) yl, phenalene- (1 -, 2-) yl, (1-, 2-, 3-, 4-, 9-) phenanthryl, quaterphenylyl which is a tetracyclic aryl (5'-phenyl-m-terphenyl-2-yl, 5′-phenyl-m-terphenyl-3-yl, 5′-phenyl-m-terphenyl-4-yl, m-quaterphenyl), triphenylene- (1-, 2- ) Yl, pyrene- (1-, 2-, 4-) yl, naphthacene- (1-, 2-, 5-) yl, perylene- (1-, 2-, 3-) which is a fused pentacyclic aryl Yl, pentacene- (1-, 2-, 5-, 6-) yl and the like.

Particularly preferred “phenyl or fused ring aryl” in R ¹ and R ² of the general formula (1) are phenyl, naphthyl and phenanthryl. Among these, phenyl, 1-naphthyl, 2-naphthyl and 9-phenanthryl Is preferred. R ¹ and R ² may be the same or different, and preferably R ¹ and R ² are the same.

Particularly preferred “aryl” in R ¹ and R ² of the general formulas (2) to (7) are phenyl, biphenylyl, terphenylyl, quaterphenylyl, naphthyl and phenanthryl. Among these, phenyl, 4-biphenylyl 1-naphthyl, 2-naphthyl and 9-phenanthryl are preferred. R ¹ and R ² may be the same or different, and preferably R ¹ and R ² are the same.

Further, "aryl" in ^{R 1} and ^{R 2} in the general formula (1) "Fused ring systems aryl" for ^{R 1} and ^{R 2} and general formula (2) to (7), the general formula (1) to (7 ) (Where R ¹ and R ² are excluded), and in this case, any two of the compounds of the general formulas (1) to (7) are directly bonded to the compound Become.

Particularly preferred “aryl” in R ³ and R ⁴ are phenyl, 4-biphenylyl, 1-naphthyl and 2-naphthyl, and R ³ and R ⁴ may be the same or different, preferably R ³ and R ⁴ are the same.

As the “alkyl” of “optionally substituted alkyl” in R ¹ , R ² , R ³ and R ⁴ of the general formulas (1) to (3) and the general formulas (4) to (7), And a branched chain alkyl, for example, a straight chain alkyl having 1 to 24 carbon atoms or a branched chain alkyl having 3 to 24 carbon atoms. Preferred “alkyl” is alkyl having 1 to 18 carbons (branched alkyl having 3 to 18 carbons). More preferable “alkyl” is alkyl having 1 to 12 carbons (branched alkyl having 3 to 12 carbons). More preferable “alkyl” is alkyl having 1 to 6 carbon atoms (branched alkyl having 3 to 6 carbon atoms). Particularly preferred “alkyl” is alkyl having 1 to 4 carbon atoms (branched alkyl having 3 to 4 carbon atoms).

  Specific examples of “alkyl” include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s-butyl, t-butyl, n-pentyl, isopentyl, neopentyl, t-pentyl, n-hexyl, 1 -Methylpentyl, 4-methyl-2-pentyl, 3,3-dimethylbutyl, 2-ethylbutyl, n-heptyl, 1-methylhexyl, n-octyl, t-octyl, 1-methylheptyl, 2-ethylhexyl, 2 -Propylpentyl, n-nonyl, 2,2-dimethylheptyl, 2,6-dimethyl-4-heptyl, 3,5,5-trimethylhexyl, n-decyl, n-undecyl, 1-methyldecyl, n-dodecyl, n-tridecyl, 1-hexylheptyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-hept Decyl, n- octadecyl, such as n- eicosyl, and the like.

“Cycloalkyl” of “optionally substituted cycloalkyl” in R ¹ and R ² of general formulas (1) to (3) and general formulas (4) to (7) is, for example, 3 to 3 carbon atoms. Twelve cycloalkyls. Preferred “cycloalkyl” is cycloalkyl having 3 to 10 carbon atoms. More preferred “cycloalkyl” is cycloalkyl having 3 to 8 carbon atoms. More preferred “cycloalkyl” is cycloalkyl having 3 to 6 carbon atoms.

  Specific examples of “cycloalkyl” include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, methylcyclopentyl, cycloheptyl, methylcyclohexyl, cyclooctyl, and dimethylcyclohexyl.

Examples of the “substituent” in R ¹ and R ² of the general formula (1) include alkyl, cycloalkyl, phenyl, and condensed ring system aryl. Preferred examples of these include the above-mentioned “alkyl” column. And those described in the column “cycloalkyl” above, and those described in the column “phenyl or fused ring aryl” in R ¹ and R ² of the general formula (1). .

Examples of the “substituent” in R ¹ and R ² of the general formulas (2) to (7) include alkyl, cycloalkyl, and aryl. Preferred examples of these include each in the above-mentioned “alkyl” column. Examples thereof include those described above, those described in the “cycloalkyl” column, and those described in the “aryl” column.

Examples of the “substituent” in R ³ and R ⁴ in the general formulas (1) to (7) include alkyl, cycloalkyl, and aryl. Preferred examples of these include each in the above-mentioned “alkyl” column. Examples thereof include those described above, those described in the “cycloalkyl” column, and those described in the “aryl” column.

Further, the “substituent” in R ¹ and R ² in the general formulas (1) to (7) is a compound of the general formulas (1) to (7) (however, a structural portion excluding R ¹ and R ² ). In this case, any two of the compounds of the general formulas (1) to (7) are connected via “aryl” or “phenyl or fused ring aryl”.

Specific examples of the “substituent” in R ¹ , R ² , R ³ and R ⁴ include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s-butyl, t-butyl, and n-pentyl. , Isopentyl, neopentyl, t-pentyl, n-hexyl, n-heptyl, n-octyl, t-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n -Alkyl such as pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl; cycloalkyl such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl; phenyl, biphenylyl (R ^{1 in} general formula (1) and except as substituent to R ^2), naphthyl, terphenylyl (general Except The substituent of the ^{R 1} and ^{R 2} (1)), aryl and phenanthryl; methylphenyl, ethylphenyl, s- butylphenyl, t- butyl phenyl, 1-methylnaphthyl, 2-methylnaphthyl, 1 , 6-dimethylnaphthyl, 2,6-dimethylnaphthyl, alkylaryl such as 4-t-butylnaphthyl and the like. The number of substituents is, for example, the maximum possible number of substitution, preferably 0-3, more preferably 0-2, and even more preferably 0 (unsubstituted).

At least one of R ¹ and R ² is selected to be optionally substituted aryl or optionally substituted phenyl or fused ring system aryl, but preferably both R ¹ and R ² are substituted Optionally substituted aryl or optionally substituted phenyl or fused ring system aryl, in which case it is more preferred that the same group is selected for both R ¹ and R ² .

R ³ and R ⁴ may be bonded to form a ring. As a result, cyclobutane, cyclopentane, cyclopentene, cyclopentadiene, cyclohexane, fluorene, indene, etc. are included in the 5-membered ring of the fluorene skeleton or benzofluorene skeleton. May be spiro-bonded.

Further, hydrogen in the fluorene ring, benzofluorene ring, dibenzofluorene ring, indenotriphenylene ring or indenopyrene ring constituting the compounds represented by the general formulas (1) to (3) and the general formulas (4) to (7) All or some of the atoms and hydrogen atoms in R ^{1 to} R ⁴ that are substituents may be deuterium.

<Triple energy of light emitting auxiliary layer material>
The role of the light-emitting auxiliary layer is to suppress or prevent the triplet excitons generated in the light-emitting layer from diffusing into the electron transport layer (by confining the triplet excitons in the light-emitting layer). In other words, a TTF phenomenon is caused. The present invention is not limited to a specific principle. To achieve this role, for example, the triplet energy E ^T _a of the light emitting auxiliary layer material is changed to the triplet energy E ^T _h of the host material of the light emitting layer. The larger one is preferable. Further, as will be described later, the triplet energy relationship between the host material forming the light emitting layer and the dopant material preferably satisfies the relationship E ^T _h <E ^T _d , and thus the triplet energy E of the light emitting auxiliary layer material. ^T _a is more preferably greater than triplet energy E ^T _d of the dopant material of the luminescent layer. In this way, singlet excitons can be efficiently generated from the host triplet excitons in the light emitting layer, and this singlet excitons are transferred onto the fluorescent light-emitting dopant to optically deactivate energy. Can be done automatically.

  In this specification, the triplet energy means a difference between the energy in the lowest excited triplet state and the energy in the ground state, and the singlet energy (sometimes referred to as an energy gap) is the energy in the lowest excited singlet state and the ground. The difference in energy in the state.

The ring-condensed fluorene compound and / or fluorene compound as the light emitting auxiliary layer material according to the present invention, particularly, the benzofluorene compound, dibenzofluorene compound, indenotriphenylene compound, indenopyrene compound and fluorene compound are derived from the specific structure described above. Triplet excitons generated in the light-emitting layer for most materials commonly used as host materials and fluorescent light-emitting dopant materials for organic EL devices due to their relatively high triplet energy E ^T _a Can be suppressed or prevented from diffusing into the electron transport layer. As a result, the TTF phenomenon can be efficiently generated in the light emitting layer. Moreover, this effect can be heightened especially by combining with a specific host material and a fluorescent light-emitting dopant material described later.

<Affinity of light emitting auxiliary layer material>
The next role of the light emission auxiliary layer is to efficiently inject electrons from the cathode to the light emitting layer. This role is originally assumed by the electron transport layer (and the electron injection layer). However, since the light emission auxiliary layer is disposed between the light emitting layer and the electron transport layer, electron injection from the electron transport layer to the light emitting layer is performed. It is preferable not to greatly reduce or inhibit the properties. When the electron injection property to the light emitting layer is greatly reduced, the density of triplet excitons is reduced by reducing electron-hole recombination in the light emitting layer, and the collision frequency of triplet excitons is reduced. The TTF phenomenon will not occur efficiently. Although the present invention is not limited to a specific principle, in order to achieve this role, for example, the relationship between the affinity A _a of the light emitting auxiliary layer material and the affinity A _e of the electron transport layer material is expressed as A _a It is preferable to satisfy> A _e −0.8 eV. This relationship preferably satisfies A _a > A _e −0.6 eV, and more preferably satisfies A _a > A _e −0.5 eV. If electron injection from the electron transport layer to the light emission auxiliary layer is greatly impaired, electrons accumulate in the electron transport layer, causing high voltage, and the stored electrons collide with triplet excitons to quench energy. there is a possibility.

The ring-condensed fluorene compound and / or fluorene compound as the light emitting auxiliary layer material according to the present invention, particularly, the benzofluorene compound, dibenzofluorene compound, indenotriphenylene compound, indenopyrene compound and fluorene compound are derived from the specific structure described above. since having a relatively large affinity a _a, for most materials commonly used as an electron transporting material for an organic EL element, or greatly reducing the injection of electrons into the light emitting layer from the electron transporting layer, There is no hindrance. Moreover, this effect can be heightened especially by combining with the specific electron transport layer material mentioned later.

<Specific compounds of light emitting auxiliary layer material>
Specific examples of the material for the light emitting auxiliary layer include all compounds obtained from combinations of the central skeleton shown below, the substituents R ¹ and R ^2, and the substituents R ³ and R ⁴ . However, the following formulas (5) to (12) are not selected as the substituents R ¹ and R ² of the central skeleton (fluorene skeleton) of the following formula (1).

That is, as a specific compound of the light emitting auxiliary layer material, the central skeleton selected from any one of the above formulas (1) to (3) and the formulas (4) to (7) has the above formula (1) to Substituents R ¹ and R ² selected from (8) and any one of formulas (13) to (19) are bonded to each other, and R ¹ and R ² may be different or the same. Examples thereof include a compound to which a substituent R ³ or R ⁴ selected from any one of (1) to (10) is bonded (R ³ and R ⁴ may be different or the same). However, the following formulas (5) to (12) are not selected as the substituents R ¹ and R ² of the central skeleton (fluorene skeleton) of the following formula (1). In the above formula, Formula (5) as a preferred example of the substituents R ³ and R ⁴ represents a form in which the 5-membered ring in the structure of Formula (5) is spiro-bonded to the 5-membered ring of the central skeleton, and “Me "Methyl", "Et" means ethyl, "tBu" means t-butyl, "Hexyl" means hexyl, and "Octyl" means octyl.

  In particular, as the fluorene compound of the general formula (1), a compound represented by any of the following formulas is preferable.

  In particular, as the benzofluorene compound of the general formula (2), a compound represented by any of the following formulas is preferable.

  In particular, as the benzofluorene compound of the general formula (3), a compound represented by any of the following formulas is preferable.

  In particular, as the dibenzofluorene compound of the general formula (4), a compound represented by any of the following formulas is preferable.

  In particular, as the indenotriphenylene compound of the general formula (5), a compound represented by any one of the following formulas is preferable.

  In particular, as the indenotriphenylene compound of the general formula (6), a compound represented by any of the following formulas is preferable.

  In particular, as the indenopyrene compound of the general formula (7), a compound represented by any of the following formulas is preferable.

More preferable compounds are the following compounds.
Formula (1-1), Formula (1-3), Formula (1-5), Formula (1-7) to Formula (1-9), Formula (1-11);
Formula (1-21), Formula (1-23), Formula (1-25), Formula (1-27) to Formula (1-29), Formula (1-31);
Formula (1-41), Formula (1-43), Formula (1-45), Formula (1-47) to Formula (1-49), Formula (1-51);
Formula (1-63), Formula (1-67), Formula (1-73), Formula (1-77), Formula (1-81), Formula (1-83), Formula (1-87);
Formula (2-1), Formula (2-3), Formula (2-5), Formula (2-7) to Formula (2-9), Formula (2-11);
Formula (2-21), Formula (2-23), Formula (2-25), Formula (2-27) to Formula (2-29), Formula (2-31);
Formula (2-41), Formula (2-43), Formula (2-45), Formula (2-47) to Formula (2-49), Formula (2-51);
Formula (2-62) to Formula (2-68);
Formula (2-72) to Formula (2-78);
Formula (2-82)-Formula (2-88);
Formula (2-91), Formula (2-93), Formula (2-97), Formula (2-101), Formula (2-103), Formula (2-107), Formula (2-111), Formula (2-113), formula (2-117);
Formula (3-1), Formula (3-3), Formula (3-5), Formula (3-7) to Formula (3-9), Formula (3-11);
Formula (4-1), Formula (4-3), Formula (4-5), Formula (4-7) to Formula (4-9), Formula (4-11);
Formula (5-41), Formula (5-43), Formula (5-45), Formula (5-47) to Formula (5-49), Formula (5-51);
Formula (6-1), Formula (6-3), Formula (6-5), Formula (6-7) to Formula (6-9), Formula (6-11);
Formula (7-1), Formula (7-3), Formula (7-5), Formula (7-7) to Formula (7-9), and Formula (7-11).

<Method for producing light emitting auxiliary layer material>
The benzofluorene compound represented by the general formula (2) can be produced by using a known synthesis method such as a Suzuki coupling reaction. The Suzuki coupling reaction is a method of coupling an aromatic halide or triflate with an aromatic boronic acid or an aromatic boronic acid ester using a palladium catalyst in the presence of a base. Specific examples of the reaction route for obtaining the general formula (2) by this method are as follows (Schemes 1 to 3). In addition, R < ¹ > -R < ⁴ > in each scheme is the same as the above, and TfO is a triflate.

Specific examples of the palladium catalyst used in this reaction are Pd (PPh ₃ ) ₄ , PdCl ₂ (PPh ₃ ) ₂ , Pd (OAc) ₂ , tris (dibenzylideneacetone) dipalladium (0), tris (dibenzylideneacetone). ) Dipalladium (0) chloroform complex, bis (dibenzylideneacetone) palladium (0), and the like. In order to accelerate the reaction, a phosphine compound may be added to these palladium compounds in some cases. Specific examples of the phosphine compound include tri (t-butyl) phosphine, tricyclohexylphosphine, 1- (N, N-dimethylaminomethyl) -2- (di-t-butylphosphino) ferrocene, 1- (N, N -Dibutylaminomethyl) -2- (di-t-butylphosphino) ferrocene, 1- (methoxymethyl) -2- (di-t-butylphosphino) ferrocene, 1,1'-bis (di-t-butylphosphino) ) Ferrocene, 2,2′-bis (di-t-butylphosphino) -1,1′-binaphthyl, 2-methoxy-2 ′-(di-t-butylphosphino) -1,1′-binaphthyl and the like. .

  Specific examples of the base used in this reaction are sodium carbonate, potassium carbonate, cesium carbonate, sodium bicarbonate, sodium hydroxide, potassium hydroxide, barium hydroxide, sodium ethoxide, sodium t-butoxide, sodium acetate, phosphoric acid. Tripotassium, potassium fluoride and the like.

  Furthermore, specific examples of the solvent used in this reaction are benzene, toluene, xylene, N, N-dimethylformamide, tetrahydrofuran, diethyl ether, t-butylmethyl ether, 1,4-dioxane, methanol, ethanol, Isopropyl alcohol and the like. These solvents can be appropriately selected according to the structures of the aromatic halide, triflate, aromatic boronic acid ester and aromatic boronic acid to be reacted. A solvent may be used independently and may be used as a mixed solvent.

In addition, regarding a compound in which R ³ and R ⁴ are bonded to form a ring (for example, an aliphatic ring or an aromatic ring) in the benzofluorene compound represented by the general formula (2), for example, JP 2009-184993 A It can be produced with reference to the method for producing a benzofluorene compound having a spiro structure described in 1. Paragraph [0055] of the publication describes a method for producing a compound in which a fluorene ring is spiro-bonded to a five-membered ring of a benzofluorene ring (Scheme 1c). A benzofluorene compound represented by the formula (2) can be produced. Note that M in the following scheme is Li, MgCl, MgBr, or MgI.

  The above is the method for producing the benzofluorene compound represented by the general formula (2), but the same applies to the benzofluorene compound represented by the general formula (3) and the fluorene compound represented by the general formula (1). Can be manufactured. In addition, the compounds of the present invention include those in which at least a part of the hydrogen atoms are substituted with deuterium. Such a compound can be obtained by using a raw material in which a desired portion is deuterated. It can be manufactured in the same manner.

  Further, the dibenzofluorene compound represented by the general formula (4) is also produced in the same manner with reference to the above schemes (1) to (4) by using a dibenzofluorene compound instead of the benzofluorene compound as a raw material. be able to. Moreover, the manufacturing method described in the said patent document 4 (international publication 2011/084033) can also be referred.

  In addition, with respect to the indenotriphenylene compound represented by the general formula (5) or (6), the raw material is an indenotriphenylene compound instead of the benzofluorene compound, and the above schemes (1) to (4) are referred to. Thus, it can be manufactured similarly. Moreover, the manufacturing method described in the said patent document 5 (Chinese patent application publication 1035083535) and the literature 6 (international publication 2012/086366) can also be referred.

  Also, the indenopyrene compound represented by the general formula (7) can be produced in the same manner with reference to the above schemes (1) to (4) by using an indenopyrene compound instead of the benzofluorene compound as a raw material. it can. Moreover, the manufacturing method described in the said patent document 7 (Unexamined-Japanese-Patent No. 2011-077982) and literature 8 (international publication 2010/053210) can also be referred.

<Other light emitting auxiliary layer materials>
Examples of other light emitting auxiliary layer materials include naphthalene derivatives, phenanthrene derivatives, benzophenanthrene derivatives, dibenzophenanthrene derivatives described in paragraphs [0079] to [0093] of Patent Document 2 (International Publication No. 2010/134350), for example. , Chrysene derivatives, benzochrysene derivatives, fluoranthene derivatives, triphenylene derivatives and the like, which may be used in combination with the benzofluorene compound and the fluorene compound as the light emitting auxiliary layer material according to the present invention.

3. The substrate substrate 101 of the organic EL element serves as a support for the organic EL element 100, and usually quartz, glass, metal, plastic, or the like is used. The substrate 101 is formed into a plate shape, a film shape, or a sheet shape according to the purpose. For example, a glass plate, a metal plate, a metal foil, a plastic film, a plastic sheet, or the like is used. Of these, glass plates and transparent synthetic resin plates such as polyester, polymethacrylate, polycarbonate, polysulfone and the like are preferable. In the case of a glass substrate, soda lime glass, non-alkali glass, or the like is used, and the thickness only needs to be sufficient to maintain the mechanical strength. The upper limit value of the thickness is, for example, 2 mm or less, preferably 1 mm or less. The glass material is preferably alkali-free glass because it is better to have less ions eluted from the glass. However, soda lime glass with a barrier coat such as SiO ₂ is also commercially available, so it can be used. it can. Further, the substrate 101 may be provided with a gas barrier film such as a dense silicon oxide film on at least one surface in order to improve the gas barrier property, and a synthetic resin plate, film or sheet having a low gas barrier property is used as the substrate 101. When used, it is preferable to provide a gas barrier film.

4). The anode 102 of the organic EL element serves to inject holes into the light emitting layer 105. When the hole injection layer 103 and / or the hole transport layer 104 are provided between the anode 102 and the light emitting layer 105, holes are injected into the light emitting layer 105 through these layers. .

  Examples of the material for forming the anode 102 include inorganic compounds and organic compounds. Examples of inorganic compounds include metals (aluminum, gold, silver, nickel, palladium, chromium, etc.), metal oxides (indium oxide, tin oxide, indium-tin oxide (ITO), etc.), halogenated compounds, etc. Examples thereof include metals (such as copper iodide), copper sulfide, carbon black, ITO glass, and nesa glass. Examples of the organic compound include polythiophene such as poly (3-methylthiophene), conductive polymer such as polypyrrole and polyaniline, and the like. In addition, it can select suitably from the substances used as an anode of an organic EL element.

  The resistance of the transparent electrode is not particularly limited as long as a current sufficient for light emission of the light emitting element can be supplied, but it is desirable that the resistance is low from the viewpoint of power consumption of the light emitting element. For example, an ITO substrate of 300Ω / □ or less functions as an element electrode. However, since it is now possible to supply a substrate of about 10Ω / □, for example, 100-5Ω / □, preferably 50-5Ω. It is particularly desirable to use a low resistance product of / □. The thickness of ITO can be arbitrarily selected according to the resistance value, but is usually used in a range of 100 to 300 nm.

5. The hole injection layer and the hole transport layer of the organic EL element serve to inject holes moving from the anode 102 into the light emitting layer 105 or the hole transport layer 104 efficiently. Is. The hole transport layer 104 plays a role of efficiently transporting holes injected from the anode 102 or holes injected from the anode 102 through the hole injection layer 103 to the light emitting layer 105. The hole injection layer 103 and the hole transport layer 104 are each formed by laminating and mixing one kind or two or more kinds of hole injection / transport materials or a mixture of the hole injection / transport material and the polymer binder. Is done. In addition, an inorganic salt such as iron (III) chloride may be added to the hole injection / transport material to form a layer.

  As a hole injection / transport material, it is necessary to efficiently inject and transport holes from the positive electrode between electrodes to which an electric field is applied. The hole injection efficiency is high, and the injected holes are transported efficiently. It is desirable to do. For this purpose, it is preferable to use a substance that has a low ionization potential, a high hole mobility, excellent stability, and is less likely to generate trapping impurities during production and use.

  As a material for forming the hole injection layer 103 and the hole transport layer 104, a compound conventionally used as a charge transport material for holes in a photoconductive material, a p-type semiconductor, and a hole injection layer of an organic EL element are used. In addition, any of known materials used for the hole transport layer can be selected and used. Specific examples thereof include carbazole derivatives (N-phenylcarbazole, polyvinylcarbazole, etc.), biscarbazole derivatives such as bis (N-arylcarbazole) or bis (N-alkylcarbazole), triarylamine derivatives (aromatic tertiary class). Polymer having amino in main chain or side chain, 1,1-bis (4-di-p-tolylaminophenyl) cyclohexane, N, N′-diphenyl-N, N′-di (3-methylphenyl) -4 , 4'-diaminobiphenyl, N, N'-diphenyl-N, N'-dinaphthyl-4,4'-diaminobiphenyl (hereinafter abbreviated as NPD), N, N'-diphenyl-N, N'- Di (3-methylphenyl) -4,4′-diphenyl-1,1′-diamine, N, N′-dinaphthyl-N, N′-diphenyl -4,4'-diphenyl-1,1'-diamine, triphenylamine derivatives such as 4,4 ', 4 "-tris (3-methylphenyl (phenyl) amino) triphenylamine, starburst amine derivatives, etc. Stilbene derivatives, phthalocyanine derivatives (metal-free, copper phthalocyanine, etc.), pyrazoline derivatives, hydrazone compounds, benzofuran derivatives, thiophene derivatives, heterocyclic compounds such as oxadiazole derivatives, porphyrin derivatives, polysilanes, etc. Polycarbonate, styrene derivatives, polyvinyl carbazole, polysilane, etc. having a monomer in the side chain are preferable, but a compound that forms a thin film necessary for the production of a light-emitting element, can inject holes from the anode, and can further transport holes. If limited No.

  It is also known that the conductivity of organic semiconductors is strongly influenced by the doping. Such an organic semiconductor matrix material is composed of a compound having a good electron donating property or a compound having a good electron accepting property. Strong electron acceptors such as tetracyanoquinone dimethane (TCNQ) or 2,3,5,6-tetrafluorotetracyano-1,4-benzoquinone dimethane (F4TCNQ) are known for doping of electron donor materials. (For example, the document “M. Pfeiffer, A. Beyer, T. Fritz, K. Leo, Appl. Phys. Lett., 73 (22), 3202-3204 (1998)”) and the document “J. Blochwitz, M Pheiffer, T. Fritz, K. Leo, Appl. Phys. Lett., 73 (6), 729-731 (1998)). These generate so-called holes by an electron transfer process in an electron donating base material (hole transport material). Depending on the number and mobility of holes, the conductivity of the base material varies considerably. Known matrix substances having hole transporting properties include, for example, benzidine derivatives (TPD and the like), starburst amine derivatives (TDATA and the like), and specific metal phthalocyanines (particularly zinc phthalocyanine ZnPc and the like). 2005-167175).

6). The light emitting layer 105 of the organic EL element emits light by recombining holes injected from the anode 102 and electrons injected from the cathode 108 between electrodes to which an electric field is applied. The material for forming the light-emitting layer 105 may be a compound that emits light by being excited by recombination of holes and electrons (a light-emitting compound), can form a stable thin film shape, and is in a solid state And a compound exhibiting strong fluorescence emission efficiency.

  The light emitting layer may be either a single layer or a plurality of layers, each formed of a light emitting material (host material, dopant material), which may be a mixture of a host material and a dopant material or a host material alone. Or either. That is, in each layer of the light emitting layer, only the host material or the dopant material may emit light, or both the host material and the dopant material may emit light. Each of the host material and the dopant material may be one kind or a plurality of combinations. The dopant material may be included in the host material as a whole, or may be included partially. The amount of dopant used varies depending on the dopant and may be determined according to the characteristics of the dopant. The standard of the amount of the dopant used is preferably 0.001 to 50% by weight, more preferably 0.1 to 10% by weight, and further preferably 1 to 5% by weight of the entire light emitting material. As a doping method, it can be formed by a co-evaporation method with a host material, but it may be pre-mixed with the host material and then simultaneously deposited.

In particular, it is preferable to form a light-emitting layer from a host material and a fluorescent light-emitting dopant material having a peak at an emission wavelength of 400 to 500 nm (the peak wavelength is toluene having a concentration of 10 ⁻⁵ to 10 ⁻⁶ mol / liter. The peak wavelength of the emission spectrum with the maximum emission intensity in the emission spectrum measured in the solution). Holes injected from the anode are injected into the light emitting layer through the hole injection / transport layer, and electrons injected from the cathode are injected into the light emitting layer through the electron injection / transport layer and the light emission auxiliary layer. After that, holes and electrons recombine in the light emitting layer, and singlet excitons and triplet excitons are generated.

In this case, recombination occurs in two ways: on the host molecule and on the dopant molecule. Here, the triplet energy E ^T _d of the dopant material is preferably larger than the triplet energy E ^T _h of the host material. By making this energy relationship (E ^T _h <E ^T _d ), the triplet exciton generated by recombination on the host does not move to a dopant having a higher triplet energy, and on the dopant molecule. The triplet exciton generated by recombination in swiftly transfers energy to the host molecule. That is, the density of triplet excitons on the host can be increased, and singlet excitons can be efficiently generated by efficiently colliding triplet excitons on the host (efficiently). TTF phenomenon). Furthermore, since the singlet energy E ^S _d of the dopant is smaller than the singlet energy E ^S _h of the host, singlet excitons generated by the TTF phenomenon transfer energy from the host to the dopant and contribute to the fluorescence emission of the dopant. To do. Originally, in a dopant used in a fluorescent element, a transition from an excited triplet state to a ground state is forbidden. In such a transition, the triplet exciton does not undergo optical energy deactivation and is thermally depleted. It was alive. However, by making the relationship between the triplet energy of the host and the dopant as described above, singlet excitons are efficiently generated by collision with each other before the triplet excitons are thermally deactivated, and the light emission efficiency. Can be improved.

As for the selection of the host material and the dopant material in consideration of the triplet energy of the light emission auxiliary layer, as described above, the benzofluorene compound and the fluorene compound as the light emission auxiliary layer material of the present invention have a relatively high triplet energy E. because having a ^T _a, and if selecting the materials commonly used as host material and the fluorescent luminescent dopant material for organic EL devices, confine the triplet excitons generated in the luminescent layer into the light emitting layer efficiently In particular, the TTF phenomenon can be generated.

In order to generate the TTF phenomenon more efficiently, the present invention is not limited to a specific principle. However, the triplet energy E ^{Th of} the host material is the triplet energy E _Th of the light emitting auxiliary layer material. it is preferable to select a smaller than ^T _a. In addition, it is preferable to select a dopant material whose triplet energy E ^T _d is smaller than the triplet energy E ^T _a of the light emitting auxiliary layer material.

<Host material>
Examples of the host material include anthracene derivatives and pyrene derivatives.

<Anthracene derivatives as host materials>
An anthracene derivative is represented by the following formula (H1), for example.

In the above formula (H1),
R ^{11 to} R ¹⁸ are each independently hydrogen, alkyl (preferably alkyl having 1 to 12 carbons), cycloalkyl (preferably cycloalkyl having 3 to 12 carbons) or aryl (preferably having 6 to 6 carbons). 30 aryl),
Ar ¹¹ and Ar ¹² are each independently an optionally substituted aryl (preferably an optionally substituted aryl having 6 to 30 carbon atoms);
n is an integer of 1 to 3, and when n is 2 or more, each anthracene structure shown in square brackets may be the same or different, and
At least one hydrogen in the anthracene derivative may be substituted with deuterium.

Ar ¹¹ and Ar ¹² are each independently an optionally substituted aryl (preferably an optionally substituted aryl having 6 to 30 carbon atoms), and the same even if Ar ¹¹ and Ar ¹² are different. It may be. Preferable aryl is aryl having 6 to 18 carbon atoms, more preferably aryl having 6 to 14 carbon atoms, and further preferably aryl having 6 to 12 carbon atoms.

  Specific examples of “aryl having 6 to 30 carbon atoms” include phenyl as monocyclic aryl, (1-, 2-) naphthyl as condensed bicyclic aryl, and acenaphthylene- (as condensed tricyclic aryl. 1-, 3-, 4-, 5-) yl, fluorene- (1-, 2-, 3-, 4-, 9-) yl, phenalen- (1-, 2-) yl, (1-, 2 -, 3-, 4-, 9-) phenanthryl, fused tetracyclic aryl triphenylene- (1-, 2-) yl, pyrene- (1-, 2-, 4-) yl, naphthacene- (1- , 2-, 5-) yl, condensed pentacyclic aryl perylene- (1-, 2-, 3-) yl, pentacene- (1-, 2-, 5-, 6-) yl and the like. .

  Preferred examples of the “aryl having 6 to 30 carbon atoms” include phenyl, naphthyl, phenanthryl, chrysenyl, triphenylenyl and the like, more preferably phenyl, 1-naphthyl, 2-naphthyl and phenanthryl, and particularly preferably phenyl, 1 -Naphthyl or 2-naphthyl.

  The substituent for the “aryl having 6 to 30 carbon atoms” is not particularly limited as long as the desired characteristics can be obtained, but preferably an alkyl having 1 to 12 carbon atoms and a cycloalkyl having 3 to 12 carbon atoms. Alternatively, aryl having 6 to 18 carbon atoms can be used.

  The “alkyl having 1 to 12 carbon atoms” as the substituent may be either a straight chain or a branched chain. That is, it is a linear alkyl having 1 to 12 carbons or a branched alkyl having 3 to 12 carbons. More preferably, it is C1-C6 alkyl (C3-C6 branched alkyl), More preferably, it is C1-C4 alkyl (C3-C4 branched alkyl). is there. Specific examples include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s-butyl, t-butyl, n-pentyl, isopentyl, neopentyl, t-pentyl, n-hexyl, 1-methylpentyl, 4-methyl-2-pentyl, 3,3-dimethylbutyl, 2-ethylbutyl and the like are mentioned, and methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s-butyl or t-butyl is preferable. More preferably, isopropyl or t-butyl.

  Specific examples of the “cycloalkyl having 3 to 12 carbon atoms” as the substituent include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, methylcyclopentyl, cycloheptyl, methylcyclohexyl, cyclooctyl, and dimethylcyclohexyl. can give. Among these, cyclopentyl or cyclohexyl is preferable.

  Moreover, about the "C6-C18 aryl" as this substituent, a C6-C14 aryl is preferable and a C6-C10 aryl is especially preferable. Specific examples include phenyl, (2-, 3-, 4-) biphenylyl, (1-, 2-) naphthyl, (1-, 2-, 3-, 4-, 9-) phenanthryl, (1-, 2-) Triphenylenyl and the like.

Ar ¹¹ and Ar ¹² (aryl having 6 to 30 carbon atoms) preferably have no “substituent”, but when having a substituent, the number of substituents is, for example, the maximum number of substitutable substituents. The number is preferably 1 to 3, more preferably 1 to 2, and still more preferably 1.

R ^{11 to} R ¹⁸ are each independently hydrogen, alkyl (preferably alkyl having 1 to 12 carbons), cycloalkyl (preferably cycloalkyl having 3 to 12 carbons) or aryl (preferably having 6 to 6 carbons). 30 aryl).

A R ¹¹ to R ¹⁸ "alkyl having 1 to 12 carbon atoms", the "cycloalkyl having 3 to 12 carbon atoms" and "aryl having 6 to 30 carbon atoms", its detailed description is the ^{Ar 11} and Ar The description in column ¹² can be cited.

  n is an integer of 1 to 3. When n is 2 or more, the anthracene structures shown in square brackets may be the same or different. Preferred n is 1 or 2, and more preferred n is 1.

  The anthracene derivative represented by the above formula (H1) can be produced using a known raw material and a known synthesis method (for example, see JP 2012-104806 A).

Moreover, what is represented by a following formula (H2) as an anthracene derivative is also preferable.

In the above formula (H2),
R ¹¹ ~R ^{18, Ar 11} and n, can be cited to the description of ^{R 11 ~R} 18, ^Ar 11 and n in the formula (H1),
Each A is independently hydrogen, alkyl having 1 to 4 carbon atoms, cycloalkyl having 3 to 6 carbon atoms, phenyl or naphthyl, m is an integer of 1 to 5;
At least one hydrogen in the anthracene derivative may be substituted with deuterium.
In addition, about a C1-C4 alkyl and a C3-C6 cycloalkyl, the description in Formula (H1) can be cited.

  The anthracene derivative represented by the above formula (H2) can be produced using a known raw material and a known synthesis method (for example, see JP 2012-104806 A).

  Specific examples of the anthracene derivatives represented by the above formulas (H1) and (H2) include those shown below.

<Pyrene derivatives as host materials>
A pyrene derivative is represented by the following formula (H3), for example.

In the above formula (H3),
^{R 11 ~R 18, Ar 11,} Ar 12 and n, can be cited to the description of ^{R 11 ~R 18, Ar 11,} Ar 12 and n in the formula (H1), and,
At least one hydrogen in the pyrene derivative may be substituted with deuterium.

  The pyrene derivative represented by the above formula (H3) can be produced using a known raw material and a known synthesis method.

Moreover, what is represented by a following formula (H4) as a pyrene derivative is also preferable.

In the above formula (H4),
Any one of R ^{11 to} R ¹⁸ , Ar ¹¹ and Ar ¹² is a linking group to φ, and other than that, quote the description of R ^{11 to} R ¹⁸ , Ar ¹¹ and Ar ¹² in formula (H1). Can
φ is an n-valent aryl ring (preferably an n-valent benzene ring, naphthalene ring, anthracene ring, fluorene ring, benzofluorene ring, phenalene ring, phenanthrene ring or triphenylene ring), and n is an integer of 1 to 4. Yes, and
At least one hydrogen in the pyrene derivative may be substituted with deuterium.

  The pyrene derivative represented by the above formula (H4) can be produced using a known raw material and a known synthesis method.

<Other host materials>
Other host materials include, for example, metal chelated oxinoid compounds such as tris (8-quinolinolato) aluminum, bisstyryl derivatives such as bisstyrylanthracene derivatives and distyrylbenzene derivatives, tetraphenylbutadiene derivatives, coumarin derivatives, oxadiazoles Derivatives, pyrrolopyridine derivatives, perinone derivatives, cyclopentadiene derivatives, thiadiazolopyridine derivatives, pyrrolopyrrole derivatives, fluorene derivatives, benzofluorene derivatives, polymer systems, polyphenylene vinylene derivatives, polyparaphenylene derivatives, polythiophene derivatives, and the chemical industry The compounds described in the June 2004 issue, page 13, and the references cited therein, etc. may be mentioned and used in combination with the host material described above. It can be.

<Dopant material>
Examples of the dopant material include amine-containing benzofluorene derivatives, amine-containing pyrene derivatives, non-amine-containing pyrene derivatives, amine-containing chrysene derivatives, and amine-containing styryl derivatives.

<Amine-containing benzofluorene derivatives as dopant materials>
The amine-containing benzofluorene derivative is represented by, for example, the following formula (D1).

In the above formula (D1),
R ¹¹ and R ¹² are each independently alkyl (preferably alkyl having 1 to 12 carbons), cycloalkyl (preferably cycloalkyl having 3 to 12 carbons) or aryl (preferably having 6 to 30 carbons). Aryl),
Ar ^{11 to} Ar ¹⁴ are each independently an optionally substituted aryl (preferably an optionally substituted aryl having 6 to 30 carbon atoms), and Ar ¹¹ and Ar ¹³ or Ar ¹² and Ar ^14. May combine to form a ring, and
At least one hydrogen in the amine-containing benzofluorene derivative may be substituted with deuterium.
In the above formula (D1), an example in which two amino groups (—N (Ar) ₂ ) are substituted is shown, but an amine-containing benzofluorene derivative in which one of them is a hydrogen atom, that is, an amino group ( It may be an amine-containing benzofluorene derivative in which only one —N (Ar) ₂ ) is substituted.

Ar ^{11 to} Ar ¹⁴ are each independently an optionally substituted aryl (preferably an optionally substituted aryl having 6 to 30 carbon atoms), and Ar ^{11 to} Ar ¹⁴ are all different from each other. May be the same. Preferable aryl is aryl having 6 to 18 carbon atoms, more preferably aryl having 6 to 14 carbon atoms, and further preferably aryl having 6 to 12 carbon atoms.

  Specific examples of “aryl having 6 to 30 carbon atoms” include phenyl as monocyclic aryl, (1-, 2-) naphthyl as condensed bicyclic aryl, and acenaphthylene- (as condensed tricyclic aryl. 1-, 3-, 4-, 5-) yl, fluorene- (1-, 2-, 3-, 4-, 9-) yl, phenalen- (1-, 2-) yl, (1-, 2 -, 3-, 4-, 9-) phenanthryl, fused tetracyclic aryl triphenylene- (1-, 2-) yl, pyrene- (1-, 2-, 4-) yl, naphthacene- (1- , 2-, 5-) yl, condensed pentacyclic aryl perylene- (1-, 2-, 3-) yl, pentacene- (1-, 2-, 5-, 6-) yl and the like. .

  Preferred examples of the “aryl having 6 to 30 carbon atoms” include phenyl, naphthyl, phenanthryl, chrysenyl, triphenylenyl and the like, more preferably phenyl, 1-naphthyl, 2-naphthyl and phenanthryl, and particularly preferably phenyl, 1 -Naphthyl or 2-naphthyl.

Ar ¹¹ and Ar ¹³ or Ar ¹² and Ar ¹⁴ may be bonded to form a ring. For example, when Ar ¹¹ and Ar ¹³ (or Ar ¹² and Ar ¹⁴ ) are phenyl groups, they are bonded. Thus, a carbazole ring is formed including “N (nitrogen atom)” in the amine-containing benzofluorene derivative, and when one or both are naphthyl groups, a benzocarbazole ring or a dibenzocarbazole ring is formed.

  The substituent for “aryl having 6 to 30 carbon atoms” is not particularly limited as long as the desired characteristics can be obtained, and preferably, alkyl, cycloalkyl, aryl, substituted silyl, cyano, and fluorine are exemplified. .

  Specific examples of the substituent include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s-butyl, t-butyl, n-pentyl, isopentyl, neopentyl, t-pentyl, n-hexyl, n- Alkyl such as heptyl, n-octyl, t-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl; cycloalkyl such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl; phenyl, Aryl such as biphenylyl, naphthyl, terphenylyl, phenanthryl; methylphenyl, ethylphenyl, s-butylphenyl, t-butylphenyl, 1-methylnaphthyl, 2-methylnaphthyl, 1,6-dimethylnaphthyl, 2,6-dimethylnaphthyl 4-t-Buchi Cyano; alkylaryl such as naphthyl fluorine and the like.

When the substituent is an alkyl group and Ar ¹¹ (or Ar ^{12 to} Ar ¹⁴ ) is substituted by two, they may be bonded to form a ring, such as cyclopentane. A ring, a cyclohexane ring, etc. are mentioned.

  When the substituent is “substituted silyl”, the three hydrogens in the silyl group are each independently methyl, ethyl, propyl, isopropyl, butyl, s-butyl, t-butyl, cyclobutyl, cyclopentyl, cyclohexyl, phenyl, biphenylyl. Or the thing substituted by naphthyl etc. is mentioned.

  Specific examples of the “substituted silyl” include trimethylsilyl, triethylsilyl, tripropylsilyl, triisopropylsilyl, tributylsilyl, tris-butylsilyl, trit-butylsilyl, ethyldimethylsilyl, propyldimethylsilyl, isopropyldimethylsilyl, butyldimethyl Silyl, s-butyldimethylsilyl, t-butyldimethylsilyl, methyldiethylsilyl, propyldiethylsilyl, isopropyldiethylsilyl, butyldiethylsilyl, s-butyldiethylsilyl, t-butyldiethylsilyl, methyldipropylsilyl, ethyldipropyl Silyl, butyldipropylsilyl, s-butyldipropylsilyl, t-butyldipropylsilyl, methyldiisopropylsilyl, ethyldiisopropylsilyl, butyldiiso Ropirushiriru, s- butyl diisopropylsilyl include trialkylsilyl such as t- butyl diisopropylsilyl. In addition, phenyldimethylsilyl, phenyldiethylsilyl, phenyldi-t-butylsilyl, methyldiphenylsilyl, ethyldiphenylsilyl, propyldiphenylsilyl, isopropyldiphenylsilyl, butyldiphenylsilyl, s-butyldiphenylsilyl, t-butyldiphenylsilyl, triphenylsilyl Etc.

The "alkyl having 1 to 12 carbon atoms" in R ¹¹ and ^{R 12,} which may be linear or branched. That is, it is a linear alkyl having 1 to 12 carbons or a branched alkyl having 3 to 12 carbons. More preferably, it is C1-C6 alkyl (C3-C6 branched alkyl), More preferably, it is C1-C4 alkyl (C3-C4 branched alkyl). is there. Specific examples include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s-butyl, t-butyl, n-pentyl, isopentyl, neopentyl, t-pentyl, n-hexyl, 1-methylpentyl, 4-methyl-2-pentyl, 3,3-dimethylbutyl, 2-ethylbutyl and the like are mentioned, and methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s-butyl or t-butyl is preferable. More preferably, isopropyl or t-butyl.

Specific examples of the “C3-C12 cycloalkyl” in R ¹¹ and R ¹² include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, methylcyclopentyl, cycloheptyl, methylcyclohexyl, cyclooctyl, and dimethylcyclohexyl. It is done. Among these, cyclopentyl or cyclohexyl is preferable.

As the “aryl having 6 to 30 carbon atoms” in R ¹¹ and R ¹² , the description in the above-mentioned column of Ar ^{11 to} Ar ¹⁴ can be cited for the specific description.

  The amine-containing benzofluorene derivative represented by the above formula (D1) can be produced using a known raw material and a known synthesis method.

<Amine-containing pyrene derivative as dopant material>
The amine-containing pyrene derivative is represented, for example, by the following formula (D2).

In the above formula (D2),
R ^{11 to} R ¹⁸ are each independently hydrogen, an optionally substituted alkyl (preferably an optionally substituted alkyl having 1 to 12 carbons), or an optionally substituted cycloalkyl (preferably An optionally substituted cycloalkyl having 3 to 12 carbon atoms), an optionally substituted aryl (preferably an optionally substituted aryl having 6 to 30 carbon atoms), or an optionally substituted heteroaryl. (Preferably heteroaryl having 5 to 30 ring atoms which may be substituted),
Ar ^{11 to} Ar ¹⁴ each independently represents an optionally substituted aryl (preferably an optionally substituted aryl having 6 to 30 carbon atoms), or an optionally substituted heteroaryl (preferably substituted) An optionally substituted heteroaryl having 5 to 30 ring atoms), and
At least one hydrogen in the amine-containing pyrene derivative may be substituted with deuterium.
In the above formula (D2), an example in which two amino groups (—N (Ar) ₂ ) are substituted is shown. An amine-containing pyrene derivative in which only one N (Ar) ₂ ) is substituted may be used.

“Aryl” of “optionally substituted aryl” in Ar ^{11 to} Ar ¹⁴ is aryl having 6 to 30 carbons, and preferable “aryl” is aryl having 6 to 16 carbons, more preferably carbon. It is aryl of formula 6-12.

  Specific examples of “aryl” include phenyl as monocyclic aryl, (1-, 2-) naphthyl as condensed bicyclic aryl, and acenaphthylene- (1-, 3-, as condensed tricyclic aryl). 4-, 5-) yl, fluorene- (1-, 2-, 3-, 4-, 9-) yl, phenalen- (1-, 2-) yl, (1-, 2-, 3-, 4 -, 9-) phenanthryl, condensed tetracyclic aryl triphenylene- (1-, 2-) yl, pyrene- (1-, 2-, 4-) yl, naphthacene- (1-, 2-, 5- ) Yl, condensed pentacyclic aryl perylene- (1-, 2-, 3-) yl, pentacene- (1-, 2-, 5-, 6-) yl and the like.

Particularly preferred “aryl” in Ar ^{11 to} Ar ¹⁴ is phenyl, biphenylyl, terphenylyl, quaterphenylyl, naphthyl and phenanthryl, and among these, phenyl, 4-biphenylyl, 1-naphthyl and 2-naphthyl are preferred. .

“Heteroaryl” of “optionally substituted heteroaryl” in Ar ^{11 to} Ar ¹⁴ is heteroaryl having 5 to 30 ring atoms, and preferred “heteroaryl” is 5 to 24 ring atoms. More preferably a heteroaryl having 5 to 18 ring atoms, and particularly preferably a heteroaryl having 5 to 12 ring atoms.

  Examples of the “heteroaryl” include a heterocyclic group containing 1 to 5 heteroatoms selected from oxygen, sulfur and nitrogen in addition to carbon as a ring constituent atom, such as an aromatic heterocyclic group. Can be given.

  Examples of the “heterocyclic group” include pyrrolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, imidazolyl, oxadiazolyl, thiadiazolyl, triazolyl, tetrazolyl, pyrazolyl, pyridyl, pyrimidinyl, pyridazinyl, pyrazinyl, triazinyl, indolyl, isoindolyl, 1H-indazolyl, Benzimidazolyl, benzoxazolyl, benzothiazolyl, 1H-benzotriazolyl, quinolyl, isoquinolyl, cinnolyl, quinazolyl, quinoxalinyl, phthalazinyl, naphthyridinyl, purinyl, pteridinyl, carbazolyl, acridinyl, phenoxazinyl, phenothazinyl, phenazinyl, etc. Imidazolyl, pyridyl, carbazolyl and the like are preferable.

  Examples of the `` aromatic heterocyclic group '' include furyl, thienyl, pyrrolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, imidazolyl, pyrazolyl, oxadiazolyl, furazanyl, thiadiazolyl, triazolyl, tetrazolyl, pyridyl, pyrimidinyl, pyridazinyl, pyrazinyl, triazinyl, Benzofuranyl, isobenzofuranyl, dibenzofuranyl, benzo [b] thienyl, dibenzothiophenyl, indolyl, isoindolyl, 1H-indazolyl, benzimidazolyl, benzoxazolyl, benzothiazolyl, 1H-benzotriazolyl, quinolyl, isoquinolyl, cinnolyl Quinazolyl, quinoxalinyl, phthalazinyl, naphthyridinyl, purinyl, pteridinyl, carbazolyl, acridinyl, fur Nokisajiniru, phenothiazinyl, phenazinyl, phenoxathiinyl, thianthrenyl, etc. indolizinyl, and the like, thienyl, imidazolyl, pyridyl, dibenzofuranyl, dibenzothiophenyl, such as carbazolyl are preferable.

The “alkyl” of “optionally substituted alkyl” in R ^{11 to} R ¹⁸ may be either a straight chain or a branched chain. That is, it is a linear alkyl having 1 to 12 carbons or a branched alkyl having 3 to 12 carbons. More preferably, it is C1-C6 alkyl (C3-C6 branched alkyl), More preferably, it is C1-C4 alkyl (C3-C4 branched alkyl). is there. Specific examples include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s-butyl, t-butyl, n-pentyl, isopentyl, neopentyl, t-pentyl, n-hexyl, 1-methylpentyl, 4-methyl-2-pentyl, 3,3-dimethylbutyl, 2-ethylbutyl and the like are mentioned, and methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s-butyl or t-butyl is preferable. More preferably, isopropyl or t-butyl.

“Cycloalkyl” of “optionally substituted cycloalkyl” in R ^{11 to} R ¹⁸ is cycloalkyl having 3 to 12 carbons, and preferable “cycloalkyl” is cycloalkyl having 3 to 10 carbons. is there. More preferred “cycloalkyl” is cycloalkyl having 3 to 8 carbon atoms. More preferred “cycloalkyl” is cycloalkyl having 3 to 6 carbon atoms.

  Specific examples of “cycloalkyl” include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, methylcyclopentyl, cycloheptyl, methylcyclohexyl, cyclooctyl, and dimethylcyclohexyl.

As “optionally substituted aryl” and “optionally substituted heteroaryl” which are R ^{11 to} R ¹⁸ , refer to the description in the above-mentioned column of Ar ^{11 to} Ar ¹⁴ for the specific description. Can do.

Examples of the substituent of “optionally substituted” in Ar ^{11 to} Ar ¹⁴ and R ^{11 to} R ¹⁸ include alkyl, cycloalkyl, aryl, substituted silyl, cyano, and fluorine. Preferred examples thereof include Are those described in the “alkyl” and “cycloalkyl” columns in R ^{11 to} R ¹⁸ , and those described in the “aryl” column in Ar ^{11 to} Ar ^{14, respectively} .

Ar ^{11 to} Ar ¹⁴ and R ^{11 to} R ¹⁸ preferably have no “substituent”, but when they have a substituent, specifically, methyl, ethyl, n-propyl, isopropyl, n-butyl , Isobutyl, s-butyl, t-butyl, n-pentyl, isopentyl, neopentyl, t-pentyl, n-hexyl, n-heptyl, n-octyl, t-octyl, n-nonyl, n-decyl, n-undecyl Alkyl such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl; aryl such as phenyl, biphenylyl, naphthyl, terphenylyl, phenanthryl; methylphenyl, ethylphenyl, s-butylphenyl , T-butylphenyl, 1-methylnaphth Cyano; Le, 2-methylnaphthyl, 1,6-dimethyl naphthyl, 2,6-dimethyl-naphthyl, alkylaryl such as 4-t-butylnaphthyl and fluorine and the like.

When the “substituent” is an alkyl group and Ar ¹¹ (or Ar ^{12 to} Ar ¹⁴ ) is substituted by two, they may be bonded to form a ring. A cyclopentane ring, a cyclohexane ring, etc. are mentioned.

  In the case of “substituted silyl” as the substituent of “optionally substituted”, the three hydrogens in the silyl group are each independently methyl, ethyl, propyl, isopropyl, butyl, s-butyl, t-butyl. , Cyclobutyl, cyclopentyl, cyclohexyl, phenyl, biphenylyl or naphthyl.

  Specific examples of the “substituted silyl” include trimethylsilyl, triethylsilyl, tripropylsilyl, triisopropylsilyl, tributylsilyl, tris-butylsilyl, trit-butylsilyl, ethyldimethylsilyl, propyldimethylsilyl, isopropyldimethylsilyl, butyldimethyl Silyl, s-butyldimethylsilyl, t-butyldimethylsilyl, methyldiethylsilyl, propyldiethylsilyl, isopropyldiethylsilyl, butyldiethylsilyl, s-butyldiethylsilyl, t-butyldiethylsilyl, methyldipropylsilyl, ethyldipropyl Silyl, butyldipropylsilyl, s-butyldipropylsilyl, t-butyldipropylsilyl, methyldiisopropylsilyl, ethyldiisopropylsilyl, butyldiiso Ropirushiriru, s- butyl diisopropylsilyl include trialkylsilyl such as t- butyl diisopropylsilyl. In addition, phenyldimethylsilyl, phenyldiethylsilyl, phenyldi-t-butylsilyl, methyldiphenylsilyl, ethyldiphenylsilyl, propyldiphenylsilyl, isopropyldiphenylsilyl, butyldiphenylsilyl, s-butyldiphenylsilyl, t-butyldiphenylsilyl, triphenylsilyl Etc.

Ar ^{11 to} Ar ¹⁴ and R ^{11 to} R ¹⁸ preferably have no “substituent”, but when having a substituent, the number of substituents is, for example, the maximum number of substituents, preferably 1 to 3, more preferably 1 to 2, and still more preferably 1. In addition, at least one hydrogen in the amine-containing pyrene derivative may be substituted with deuterium.

  The amine-containing pyrene derivative represented by the above formula (D2) can be produced using a known raw material and a known synthesis method.

<Amine-free pyrene derivative as dopant material>
The amine-free pyrene derivative is represented, for example, by the following formula (D3).

In the above formula (D3),
R ^{11 to} R ¹⁶ can refer to the explanation of R ^{11 to} R ¹⁸ in the formula (D2),
Ar ^{11 to} Ar ¹⁴ can cite the explanation of Ar ^{11 to} Ar ¹⁴ in formula (D2), and
At least one hydrogen in the amine-free pyrene derivative may be substituted with deuterium.

  The amine-free pyrene derivative represented by the above formula (D3) can be produced using a known raw material and a known synthesis method.

<Amine-containing chrysene derivative as dopant material>
The amine-containing chrysene derivative is represented by, for example, the following formula (D4).

In the above formula (D4),
R ^{11 to} R ¹⁸ can refer to the explanation of R ^{11 to} R ¹⁸ in the formula (D2),
Ar ^{11 to} Ar ¹⁴ can cite the explanation of Ar ^{11 to} Ar ¹⁴ in formula (D2), and
At least one hydrogen in the amine-containing chrysene derivative may be substituted with deuterium.
Moreover, although the formula (D4) shows an example in which two amino groups (—N (Ar) ₂ ) are substituted, an amine-containing chrysene derivative in which one of them is a hydrogen atom, that is, an amino group (— An amine-containing chrysene derivative in which only one N (Ar) ₂ ) is substituted may be used.

  The amine-containing chrysene derivative represented by the above formula (D4) can be produced using a known raw material and a known synthesis method.

<Amine-containing styryl derivative as dopant material>
The amine-containing styryl derivative is represented by the following formula (D5), for example.

In the above formula (D5),
Ar ^{11 to} Ar ¹⁴ are each independently an optionally substituted aryl or an optionally substituted heteroaryl,
Ar ^{15 to} Ar ¹⁷ are each independently an optionally substituted arylene or an optionally substituted heteroarylene,
l, m, and n are each independently an integer of 1 to 3, p is an integer of 0 to 2,
When l is 2 or more, Ar ¹⁵ may be the same or different,
When m is 2 or more, Ar ¹⁶ may be the same or different,
When p is 1 or more and n is 2 or more, Ar ¹⁷ may be the same or different,
When p is 2 or more and n is 1, Ar ¹⁷ may be the same or different,
The substituent for Ar ^{11 to} Ar ¹⁷ is halogen, alkyl, aryl, heteroaryl, silyl which may be substituted, or cyano.
In the above formula (D5), an example in which two amino groups (—N (Ar) ₂ ) are substituted is shown, but an amine-containing styryl derivative in which one of them is a hydrogen atom, that is, an amino group ( An amine-containing styryl derivative in which only one N (Ar) ₂ ) is substituted may be used.

Ar ¹¹ The heteroaryl be also aryl, and substituted substituted in to Ar ^17, it is possible to cite the description of ^Ar 11 ^{to Ar 14} in Formula ^(D2), of the Ar 11 ^{to Ar 17} As the substituents alkyl, aryl, heteroaryl and optionally substituted silyl, those described as the substituents for Ar ^{11 to} Ar ¹⁴ and R ^{11 to} R ¹⁸ in formula (D2) can be cited. .

A more specific amine-containing styryl derivative is represented by the following formula (D6), for example.

In the above formula (D6),
Ar ^{11 to} Ar ¹⁴ can cite the explanation of Ar ^{11 to} Ar ¹⁴ in formula (D2), and
At least one hydrogen in the amine-containing styryl derivative may be substituted with deuterium.
In the above formula (D6), an example in which two amino groups (—N (Ar) ₂ ) are substituted is shown, but an amine-containing styryl derivative in which one of them is a hydrogen atom, that is, an amino group (— An amine-containing styryl derivative in which only one N (Ar) ₂ ) is substituted may be used.

  The amine-containing styryl derivatives represented by the above formulas (D5) and (D6) can be produced using known raw materials and known synthetic methods.

  Examples of other amine-containing styryl derivatives include N, N, N ′, N′-tetra (4-biphenylyl) -4,4′-diaminostilbene, N, N, N ′, N′-tetra (1- Naphthyl) -4,4′-diaminostilbene, N, N, N ′, N′-tetra (2-naphthyl) -4,4′-diaminostilbene, N, N′-di (2-naphthyl) -N, N'-diphenyl-4,4'-diaminostilbene, N, N'-di (9-phenanthryl) -N, N'-diphenyl-4,4'-diaminostilbene, 4,4'-bis [4 "- Bis (diphenylamino) styryl] -biphenyl, 1,4-bis [4′-bis (diphenylamino) styryl] -benzene, 2,7-bis [4′-bis (diphenylamino) styryl] -9,9- Dimethyl fluorene, 4, Examples include '-bis (9-ethyl-3-carbazovinylene) -biphenyl, 4,4'-bis (9-phenyl-3-carbazovinylene) -biphenyl, etc. In addition, JP 2003-347056 A and JP An amine-containing styryl derivative described in JP 2001-307884 A may be used.

<Other dopant materials>
Examples of other dopant materials include perylene derivatives, borane derivatives, aromatic amine derivatives, and coumarin derivatives, and compounds described in Chemical Industry, June 2004, page 13, and references cited therein. May be used in combination with the dopant materials mentioned above.

  Examples of perylene derivatives include 3,10-bis (2,6-dimethylphenyl) perylene, 3,10-bis (2,4,6-trimethylphenyl) perylene, 3,10-diphenylperylene, 3,4- Diphenylperylene, 2,5,8,11-tetra-t-butylperylene, 3,4,9,10-tetraphenylperylene, 3- (1'-pyrenyl) -8,11-di (t-butyl) perylene 3- (9′-anthryl) -8,11-di (t-butyl) perylene, 3,3′-bis (8,11-di (t-butyl) perylenyl), and the like. JP-A-11-97178, JP-A-2000-133457, JP-A-2000-26324, JP-A-2001-267079, JP-A-2001-267078, JP-A-2001-267076, Perylene derivatives described in JP-A No. 2000-34234, JP-A No. 2001-267075, JP-A No. 2001-217077 and the like may be used.

  Examples of the borane derivative include 1,8-diphenyl-10- (dimesitylboryl) anthracene, 9-phenyl-10- (dimesitylboryl) anthracene, 4- (9′-anthryl) dimesitylborylnaphthalene, 4- (10 ′). -Phenyl-9'-anthryl) dimesitylborylnaphthalene, 9- (dimesitylboryl) anthracene, 9- (4'-biphenylyl) -10- (dimesitylboryl) anthracene, 9- (4 '-(N-carbazolyl) phenyl) -10- (Dimesitylboryl) anthracene and the like. Further, borane derivatives described in International Publication No. 2000/40586 and the like may be used.

  Examples of the aromatic amine derivative include N, N, N, N-tetraphenylanthracene-9,10-diamine, 9,10-bis (4-diphenylamino-phenyl) anthracene, and 9,10-bis (4- Di (1-naphthylamino) phenyl) anthracene, 9,10-bis (4-di (2-naphthylamino) phenyl) anthracene, 10-di-p-tolylamino-9- (4-di-p-tolylamino-1) -Naphthyl) anthracene, 10-diphenylamino-9- (4-diphenylamino-1-naphthyl) anthracene, 10-diphenylamino-9- (6-diphenylamino-2-naphthyl) anthracene, [4- (4-diphenyl) Amino-phenyl) naphthalen-1-yl] -diphenylamine, [4- (4-diphenylamino-phenyl) Naphthalen-1-yl] -diphenylamine, [6- (4-diphenylamino-phenyl) naphthalen-2-yl] -diphenylamine, 4,4′-bis [4-diphenylaminonaphthalen-1-yl] biphenyl, 4, 4'-bis [6-diphenylaminonaphthalen-2-yl] biphenyl, 4,4 "-bis [4-diphenylaminonaphthalen-1-yl] -p-terphenyl, 4,4" -bis [6-diphenyl Aminonaphthalen-2-yl] -p-terphenyl and the like. Moreover, you may use the aromatic amine derivative described in Unexamined-Japanese-Patent No. 2006-156888.

  Examples of the coumarin derivative include coumarin-6 and coumarin-334. Moreover, you may use the coumarin derivative described in Unexamined-Japanese-Patent No. 2004-43646, Unexamined-Japanese-Patent No. 2001-76876, and Unexamined-Japanese-Patent No. 6-298758.

7). Electron injection layer and electron transport layer of the organic EL element The electron injection layer 107 plays a role of efficiently injecting electrons moving from the cathode 108 into the electron transport layer 106. The electron transport layer 106 plays a role of efficiently transporting electrons injected from the cathode 108 or electrons injected from the cathode 108 through the electron injection layer 107 to the light emission auxiliary layer 110. The electron transport layer 106 and the electron injection layer 107 are each formed by laminating and mixing one or more electron transport / injection materials or a mixture of the electron transport / injection material and the polymer binder.

  The electron injecting / transporting layer is a layer that administers electrons injected from the cathode and further transports electrons. It is desirable that the electron injecting electrons have high efficiency and efficiently transport the injected electrons. For this purpose, it is preferable to use a substance that has a high electron affinity, a high electron mobility, excellent stability, and is unlikely to generate trapping impurities during production and use. However, considering the transport balance between holes and electrons, if the role of effectively preventing the holes from the anode from flowing to the cathode side without recombination is mainly played, the electron transport capability is much higher. Even if it is not high, the effect of improving the luminous efficiency is equivalent to that of a material having a high electron transport capability. Therefore, the electron injection / transport layer in this embodiment may include a function of a layer that can efficiently block the movement of holes.

  In the present invention, since electrons from the electron transport layer are transported to the light emitting layer through the light emission auxiliary layer, electron injection from the electron transport layer to the light emission auxiliary layer is delayed, so that the electron injection property to the light emitting layer is delayed. In the case of a significant decrease in the electron-hole recombination in the light-emitting layer, the density of triplet excitons decreases and the collision frequency of triplet excitons decreases. As a result, the TTF phenomenon occurs efficiently. It will disappear. If electron injection from the electron transport layer to the light emission auxiliary layer is greatly impaired, electrons accumulate in the electron transport layer, causing high voltage, and the stored electrons collide with triplet excitons to quench energy. there is a possibility.

Since the benzofluorene compound and the fluorene compound as the light emitting auxiliary layer material according to the present invention have a relatively large affinity A _a derived from the specific structure described above, they are generally used as an electron transport material for an organic EL device. For most of the materials, the electron injecting property from the electron transport layer to the light emitting layer is not greatly reduced or hindered.

To further efficiently electrons injected from the electron transporting layer to the light-emitting layer is present invention Without being bound to a particular theory, the electron-transporting material, the Afeniti A _e is emitting auxiliary layer material Affinity It is preferable to select those satisfying the relationship of A _a and A _a > A _e −0.8 eV. This relationship preferably satisfies A _a > A _e −0.6 eV, and more preferably satisfies A _a > A _e −0.5 eV.

<Material for electron transport layer>
The electron transport layer material is preferably a heterocyclic ring-containing compound, and examples thereof include pyridine derivatives, thiazole derivatives, benzothiazole derivatives, benzimidazole derivatives, phenanthroline derivatives, and phosphine oxide derivatives. These materials may be used as materials for the electron injection layer.

<Pyridine derivatives as materials for electron transport layers>
The pyridine derivative is represented by, for example, the following formulas (ET1) to (ET3).

In the above formula (ET1),
φ is an n-valent aryl ring (preferably an n-valent benzene ring, naphthalene ring, anthracene ring, fluorene ring, benzofluorene ring, phenalene ring, phenanthrene ring or triphenylene ring), and n is an integer of 1 to 4. Yes,
In the above formula (ET2),
R ^{11 to} R ¹⁸ are each independently hydrogen, alkyl (preferably alkyl having 1 to 24 carbon atoms), cycloalkyl (preferably cycloalkyl having 3 to 12 carbon atoms) or aryl (preferably having 6 to 6 carbon atoms). 30 aryl),
In the above formula (ET3),
R ¹¹ and R ¹² are each independently hydrogen, alkyl (preferably alkyl having 1 to 24 carbon atoms), cycloalkyl (preferably cycloalkyl having 3 to 12 carbon atoms) or aryl (preferably having 6 to 6 carbon atoms). 30 aryl), and R ¹¹ and R ¹² may combine to form a ring,
In the above formula (ET1) to formula (ET3),
The “pyridine-based substituent” is any of the following formulas (Py-1) to (Py-15), and each pyridine-based substituent may be independently substituted with an alkyl having 1 to 4 carbon atoms. Well and
At least one hydrogen in each pyridine derivative may be substituted with deuterium.
In addition, one of the two “pyridine substituents” in the above formula (ET2) and formula (ET3) may be substituted with aryl.

The “alkyl” in R ^{11 to} R ¹⁸ may be either a straight chain or a branched chain, and examples thereof include a linear alkyl having 1 to 24 carbon atoms and a branched alkyl having 3 to 24 carbon atoms. Preferred “alkyl” is alkyl having 1 to 18 carbons (branched alkyl having 3 to 18 carbons). More preferable “alkyl” is alkyl having 1 to 12 carbons (branched alkyl having 3 to 12 carbons). More preferable “alkyl” is alkyl having 1 to 6 carbon atoms (branched alkyl having 3 to 6 carbon atoms). Particularly preferred “alkyl” is alkyl having 1 to 4 carbon atoms (branched alkyl having 3 to 4 carbon atoms).

  Specific examples of “alkyl” include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s-butyl, t-butyl, n-pentyl, isopentyl, neopentyl, t-pentyl, n-hexyl, 1 -Methylpentyl, 4-methyl-2-pentyl, 3,3-dimethylbutyl, 2-ethylbutyl, n-heptyl, 1-methylhexyl, n-octyl, t-octyl, 1-methylheptyl, 2-ethylhexyl, 2 -Propylpentyl, n-nonyl, 2,2-dimethylheptyl, 2,6-dimethyl-4-heptyl, 3,5,5-trimethylhexyl, n-decyl, n-undecyl, 1-methyldecyl, n-dodecyl, n-tridecyl, 1-hexylheptyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-hept Decyl, n- octadecyl, such as n- eicosyl, and the like.

  As the alkyl having 1 to 4 carbon atoms to be substituted with the pyridine-based substituent, the description of the above alkyl can be cited.

Examples of “cycloalkyl” in R ^{11 to} R ¹⁸ include cycloalkyl having 3 to 12 carbon atoms. Preferred “cycloalkyl” is cycloalkyl having 3 to 10 carbon atoms. More preferred “cycloalkyl” is cycloalkyl having 3 to 8 carbon atoms. More preferred “cycloalkyl” is cycloalkyl having 3 to 6 carbon atoms.

  Specific examples of “cycloalkyl” include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, methylcyclopentyl, cycloheptyl, methylcyclohexyl, cyclooctyl, and dimethylcyclohexyl.

As “aryl” in R ^{11 to} R ¹⁸ , preferred aryl is aryl having 6 to 30 carbon atoms, more preferred aryl is aryl having 6 to 18 carbon atoms, and further preferred is aryl having 6 to 14 carbon atoms. And particularly preferred is aryl having 6 to 12 carbon atoms.

  Specific examples of “aryl having 6 to 30 carbon atoms” include phenyl as monocyclic aryl, (1-, 2-) naphthyl as condensed bicyclic aryl, and acenaphthylene- (as condensed tricyclic aryl. 1-, 3-, 4-, 5-) yl, fluorene- (1-, 2-, 3-, 4-, 9-) yl, phenalen- (1-, 2-) yl, (1-, 2 -, 3-, 4-, 9-) phenanthryl, fused tetracyclic aryl triphenylene- (1-, 2-) yl, pyrene- (1-, 2-, 4-) yl, naphthacene- (1- , 2-, 5-) yl, condensed pentacyclic aryl perylene- (1-, 2-, 3-) yl, pentacene- (1-, 2-, 5-, 6-) yl and the like. .

  Preferred examples of the “aryl having 6 to 30 carbon atoms” include phenyl, naphthyl, phenanthryl, chrysenyl, triphenylenyl and the like, more preferably phenyl, 1-naphthyl, 2-naphthyl and phenanthryl, and particularly preferably phenyl, 1 -Naphthyl or 2-naphthyl.

R ¹¹ and R ¹² in the above formula (ET3) may be bonded to form a ring. As a result, the 5-membered ring of the fluorene skeleton includes cyclobutane, cyclopentane, cyclopentene, cyclopentadiene, cyclohexane, fluorene or Indene or the like may be spiro-bonded.

In the above formulas (ET1) to (ET3), the “pyridine substituent” is any one of the above formulas (Py-1) to (Py-15). Among these, the following formula (Py-21) ) To formula (Py-44).

  The pyridine derivatives represented by the above formulas (ET1) to (ET3) can be produced using known raw materials and known synthesis methods.

ベンゾチアゾール誘導体は例えば下記式（ＥＴ５）で表されるものである。

<Thiazole derivatives and benzothiazole derivatives as materials for electron transport layers>
The thiazole derivative is represented by the following formula (ET4), for example.

The benzothiazole derivative is represented by, for example, the following formula (ET5).

In the above formula (ET4) or formula (ET5),
φ is an n-valent aryl ring (preferably an n-valent benzene ring, naphthalene ring, anthracene ring, fluorene ring, benzofluorene ring, phenalene ring, phenanthrene ring or triphenylene ring), and n is an integer of 1 to 4. Yes,
The “thiazole substituent” and “benzothiazole substituent” are those in which the pyridyl group in the “pyridine substituent” in the above formulas (ET1) to (ET3) is replaced with a thiazole group or a benzothiazole group. ,
At least one hydrogen in the thiazole derivative and the benzothiazole derivative may be substituted with deuterium.

φ is preferably an anthracene ring or a fluorene ring, and the structure in this case can be cited from the above formula (ET2) or (ET3), and R ^{11 to} R ^{18 in} each formula are the above Reference can be made to those described in formula (ET2) or (ET3). Further, in the above formula (ET2) or (ET3), it is described in a form in which two pyridine-based substituents are bonded, but when these are replaced with thiazole-based substituents (or benzothiazole-based substituents), The system substituent may be replaced with a thiazole substituent (or benzothiazole substituent) (that is, n = 2), and any one pyridine substituent is a thiazole substituent (or benzothiazole substituent). And the other pyridine-based substituent may be replaced with R ^{11 to} R ¹⁸ (that is, n = 1). Further, for example, at least one of R ^{11 to} R ¹⁸ in the above formula (ET2) may be replaced with a thiazole substituent (or benzothiazole substituent), and the “pyridine substituent” may be replaced with R ^{11 to} R ^18. Good.

  The thiazole derivatives or benzothiazole derivatives represented by the above formulas (ET4) and (ET5) can be produced using known raw materials and known synthesis methods.

<Benzimidazole derivatives as materials for electron transport layers>
Benzimidazole is represented, for example, by the following formula (ET6).

In the above formula (ET6),
φ is an n-valent aryl ring (preferably an n-valent benzene ring, naphthalene ring, anthracene ring, fluorene ring, benzofluorene ring, phenalene ring, phenanthrene ring or triphenylene ring), and n is an integer of 1 to 4. Yes,
The “benzimidazole-based substituent” is obtained by replacing the pyridyl group in the “pyridine-based substituent” in the above formulas (ET1) to (ET3) with a benzimidazole group,
At least one hydrogen in the benzimidazole derivative may be substituted with deuterium.

R ¹¹ in the benzimidazole group is hydrogen, alkyl having 1 to 24 carbons, cycloalkyl having 3 to 12 carbons or aryl having 6 to 30 carbons, and R ¹¹ in the above formula (ET2) and formula (ET3) ^Eleven explanations can be cited.

φ is preferably an anthracene ring or a fluorene ring, and the structure in this case can be cited from the above formula (ET2) or (ET3), and R ^{11 to} R ^{18 in} each formula are the above Reference can be made to those described in formula (ET2) or (ET3). Further, in the above formula (ET2) or (ET3), it is described in a form in which two pyridine substituents are bonded. When these are replaced with benzimidazole substituents, both pyridine substituents are replaced with benzimidazole substituents. It may be replaced with a substituent (that is, n = 2), or any one pyridine-based substituent may be replaced with a benzimidazole-based substituent, and the other pyridine-based substituent may be replaced with R ^{11 to} R ¹⁸ ( That is, n = 1). Further, for example, at least one of R ^{11 to} R ¹⁸ in the above formula (ET2) may be replaced with a benzimidazole substituent, and the “pyridine substituent” may be replaced with R ^{11 to} R ¹⁸ .

  The benzimidazole derivative represented by the above formula (ET6) can be produced using a known raw material and a known synthesis method.

  Specific examples of the benzimidazole derivative include 1-phenyl-2- (4- (10-phenylanthracen-9-yl) phenyl) -1H-benzo [d] imidazole, 2- (4- (10- (naphthalene-2) -Yl) anthracen-9-yl) phenyl) -1-phenyl-1H-benzo [d] imidazole, 2- (3- (10- (naphthalen-2-yl) anthracen-9-yl) phenyl) -1- Phenyl-1H-benzo [d] imidazole, 5- (10- (naphthalen-2-yl) anthracen-9-yl) -1,2-diphenyl-1H-benzo [d] imidazole, 1- (4- (10 -(Naphthalen-2-yl) anthracen-9-yl) phenyl) -2-phenyl-1H-benzo [d] imidazole, 2- (4- (9,10-di (naphthalene) 2-yl) anthracen-2-yl) phenyl) -1-phenyl-1H-benzo [d] imidazole, 1- (4- (9,10-di (naphthalen-2-yl) anthracen-2-yl) phenyl ) -2-phenyl-1H-benzo [d] imidazole, 5- (9,10-di (naphthalen-2-yl) anthracen-2-yl) -1,2-diphenyl-1H-benzo [d] imidazole is there.

<Phenanthroline derivative as material for electron transport layer>
The phenanthroline derivative is represented by, for example, the following formula (ET7) or (ET8).

In the above formula (ET8),
φ is an n-valent aryl ring (preferably an n-valent benzene ring, naphthalene ring, anthracene ring, fluorene ring, benzofluorene ring, phenalene ring, phenanthrene ring or triphenylene ring), and n is an integer of 1 to 4. Yes,
In the above formula (ET7) and formula (ET8),
R ^{11 to} R ¹⁸ are each independently hydrogen, alkyl (preferably alkyl having 1 to 24 carbon atoms), cycloalkyl (preferably cycloalkyl having 3 to 12 carbon atoms) or aryl (preferably having 6 to 6 carbon atoms). 30 aryl),
At least one hydrogen in each phenanthroline derivative may be substituted with deuterium.

Alkyl in R ¹¹ to R ^18, cycloalkyl and aryl may be cited to the description of ^R 11 ^{to R 18} in the formula (ET1). In addition to the above, φ includes, for example, those of the following structural formula. In addition, R in the following structural formula is each independently hydrogen, methyl, ethyl, isopropyl, cyclohexyl, phenyl, 1-naphthyl, 2-naphthyl, biphenylyl, or terphenylyl.

  The phenanthroline derivative represented by the above formula (ET7) or (ET8) can be produced using a known raw material and a known synthesis method.

  Specific examples of the phenanthroline derivative include 4,7-diphenyl-1,10-phenanthroline, 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline, 9,10-di (1,10-phenanthroline- 2-yl) anthracene, 2,6-di (1,10-phenanthroline-5-yl) pyridine, 1,3,5-tri (1,10-phenanthroline-5-yl) benzene, 9,9′-difluor -Bis (1,10-phenanthroline-5-yl), bathocuproin, 1,3-bis (2-phenyl-1,10-phenanthroline-9-yl) benzene and the like.

<Phosphine oxide derivative as material for electron transport layer>
The phosphine oxide derivative is represented by, for example, the following formula (ET9).

In the above formula (ET9), R ^{1 to} R ³ may be the same or different, and are hydrogen, alkyl group, cycloalkyl group, aralkyl group, alkenyl group, cycloalkenyl group, alkynyl group, alkoxy group, alkylthio group, Condensation formed between aryl ether groups, aryl thioether groups, aryl groups, heterocyclic groups, halogens, cyano groups, aldehyde groups, carbonyl groups, carboxyl groups, amino groups, nitro groups, silyl groups, and adjacent substituents Selected from the ring.

Ar ¹ and Ar ² may be the same or different and are an aryl group or a heteroaryl group. However, at least one of Ar ¹ and Ar ² has a substituent, or forms a condensed ring with an adjacent substituent. n is an integer of 1 to 3, and when n is 3, R ¹ does not exist.

  Among these substituents, the alkyl group represents, for example, a saturated aliphatic hydrocarbon group such as a methyl group, an ethyl group, a propyl group, or a butyl group, which may be unsubstituted or substituted. The substituent in the case of being substituted is not particularly limited, and examples thereof include an alkyl group, an aryl group, and a heterocyclic group, and this point is common to the following description. Further, the number of carbon atoms of the alkyl group is not particularly limited, but is usually in the range of 1 to 20 from the viewpoint of availability and cost.

  The cycloalkyl group represents a saturated alicyclic hydrocarbon group such as cyclopropyl, cyclohexyl, norbornyl, adamantyl, and the like, which may be unsubstituted or substituted. Although carbon number of an alkyl group part is not specifically limited, Usually, it is the range of 3-20.

  The aralkyl group refers to an aromatic hydrocarbon group via an aliphatic hydrocarbon such as a benzyl group or a phenylethyl group, and both the aliphatic hydrocarbon and the aromatic hydrocarbon are unsubstituted or substituted. It doesn't matter. Although carbon number of an aliphatic part is not specifically limited, Usually, it is the range of 1-20.

  Moreover, an alkenyl group shows the unsaturated aliphatic hydrocarbon group containing double bonds, such as a vinyl group, an allyl group, and a butadienyl group, for example, and this may be unsubstituted or substituted. Although carbon number of an alkenyl group is not specifically limited, Usually, it is the range of 2-20.

  The cycloalkenyl group refers to an unsaturated alicyclic hydrocarbon group containing a double bond such as a cyclopentenyl group, a cyclopentadienyl group, or a cyclohexene group, which may be unsubstituted or substituted. It doesn't matter.

  The alkynyl group represents an unsaturated aliphatic hydrocarbon group containing a triple bond such as an acetylenyl group, which may be unsubstituted or substituted. Although carbon number of an alkynyl group is not specifically limited, Usually, it is the range of 2-20.

  The alkoxy group refers to, for example, an aliphatic hydrocarbon group via an ether bond such as a methoxy group, and the aliphatic hydrocarbon group may be unsubstituted or substituted. Although carbon number of an alkoxy group is not specifically limited, Usually, it is the range of 1-20.

  The alkylthio group is a group in which an oxygen atom of an ether bond of an alkoxy group is substituted with a sulfur atom.

  The aryl ether group refers to, for example, an aromatic hydrocarbon group via an ether bond such as a phenoxy group, and the aromatic hydrocarbon group may be unsubstituted or substituted. Although carbon number of an aryl ether group is not specifically limited, Usually, it is the range of 6-40.

  The arylthioether group is a group in which the oxygen atom of the ether bond of the arylether group is substituted with a sulfur atom.

  Moreover, an aryl group shows aromatic hydrocarbon groups, such as a phenyl group, a naphthyl group, a biphenyl group, a phenanthryl group, a terphenyl group, a pyrenyl group, for example. The aryl group may be unsubstituted or substituted. Although carbon number of an aryl group is not specifically limited, Usually, it is the range of 6-40.

  The heterocyclic group refers to, for example, a cyclic structural group having an atom other than carbon, such as a furanyl group, a thiophenyl group, an oxazolyl group, a pyridyl group, a quinolinyl group, or a carbazolyl group, which is unsubstituted or substituted. It doesn't matter. Although carbon number of a heterocyclic group is not specifically limited, Usually, it is the range of 2-30.

  Halogen is fluorine, chlorine, bromine or iodine.

  The aldehyde group, carbonyl group, and amino group may include those substituted with aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, heterocyclic rings, and the like.

  Further, the aliphatic hydrocarbon, alicyclic hydrocarbon, aromatic hydrocarbon, and heterocyclic ring may be unsubstituted or substituted.

  The silyl group indicates, for example, a silicon compound group such as a trimethylsilyl group, which may be unsubstituted or substituted. Although carbon number of a silyl group is not specifically limited, Usually, it is the range of 3-20. Moreover, the number of silicon is 1-6 normally.

The condensed ring formed between adjacent substituents includes, for example, Ar ¹ and R ² , Ar ¹ and R ³ , Ar ² and R ² , Ar ² and R ³ , R ² and R ³ , Ar ¹ and A conjugated or non-conjugated fused ring is formed between Ar ^{2 and the} like. Here, when n is 1, it may be formed conjugated or non-conjugated fused ring with two of R ¹ each other. These condensed rings may contain a nitrogen, oxygen, or sulfur atom in the ring structure, or may be further condensed with another ring.

  The phosphine oxide derivative represented by the above formula (ET9) can be produced using a known raw material and a known synthesis method.

<Other electron transport materials>
Other materials used for the electron transport layer and the electron injection layer include compounds conventionally used as electron transport compounds in photoconductive materials, and known materials used for the electron injection layer and the electron transport layer of organic EL devices. Any compound can be selected and used. You may use together with the material for electron carrying layers mentioned above.

  Specifically, naphthalene derivatives, anthracene derivatives, perinone derivatives, coumarin derivatives, naphthalimide derivatives, anthraquinone derivatives, diphenoquinone derivatives, diphenylquinone derivatives, perylene derivatives, thiophene derivatives, thiadiazole derivatives, quinoxaline derivatives, quinoxaline derivative polymers, benzazoles Examples thereof include compounds, pyrazole derivatives, perfluorinated phenylene derivatives, triazine derivatives, pyrazine derivatives, imidazopyridine derivatives, benzoxazole derivatives, benzothiazole derivatives, quinoline derivatives, aldazine derivatives, carbazole derivatives, indole derivatives, and bisstyryl derivatives. In addition, oxadiazole derivatives (1,3-bis [(4-t-butylphenyl) 1,3,4-oxadiazolyl] phenylene, etc.), triazole derivatives (N-naphthyl-2,5-diphenyl-1,3, etc.) 4-triazole), benzoquinoline derivatives (2,2′-bis (benzo [h] quinolin-2-yl) -9,9′-spirobifluorene, etc.), naphthyridine derivatives (bis (1-naphthyl) -4 -(1,8-naphthyridin-2-yl) phenylphosphine oxide, etc.). These materials can be used alone or in combination with different materials.

  In addition, metal complexes having electron-accepting nitrogen can also be used, such as hydroxyazole complexes such as quinolinol-based metal complexes and hydroxyphenyloxazole complexes, azomethine complexes, tropolone metal complexes, flavonol metal complexes, and benzoquinoline metal complexes. can give. These materials can be used alone or in combination with different materials.

式中、Ｒ^１〜Ｒ^６は水素または置換基であり、ＭはＬｉ、Ａｌ、Ｇａ、ＢｅまたはＺｎであり、ｎは１〜３の整数である。The quinolinol-based metal complex is a compound represented by the following general formula (E-1).

In the formula, R ^{1 to} R ⁶ are hydrogen or a substituent, M is Li, Al, Ga, Be, or Zn, and n is an integer of 1 to 3.

  Specific examples of the quinolinol-based metal complex include 8-quinolinol lithium, tris (8-quinolinolato) aluminum, tris (4-methyl-8-quinolinolato) aluminum, tris (5-methyl-8-quinolinolato) aluminum, tris (3 , 4-dimethyl-8-quinolinolato) aluminum, tris (4,5-dimethyl-8-quinolinolato) aluminum, tris (4,6-dimethyl-8-quinolinolato) aluminum, bis (2-methyl-8-quinolinolato) ( Phenolate) aluminum, bis (2-methyl-8-quinolinolato) (2-methylphenolato) aluminum, bis (2-methyl-8-quinolinolato) (3-methylphenolato) aluminum, bis (2-methyl-8- Quinolinolato) (4-me Ruphenolate) aluminum, bis (2-methyl-8-quinolinolato) (2-phenylphenolate) aluminum, bis (2-methyl-8-quinolinolato) (3-phenylphenolate) aluminum, bis (2-methyl-8- Quinolinolato) (4-phenylphenolate) aluminum, bis (2-methyl-8-quinolinolato) (2,3-dimethylphenolate) aluminum, bis (2-methyl-8-quinolinolato) (2,6-dimethylphenolate) ) Aluminum, bis (2-methyl-8-quinolinolato) (3,4-dimethylphenolate) aluminum, bis (2-methyl-8-quinolinolato) (3,5-dimethylphenolate) aluminum, bis (2-methyl) -8-quinolinolate) (3,5-di-tert-butyl) Ruphenolate) aluminum, bis (2-methyl-8-quinolinolato) (2,6-diphenylphenolate) aluminum, bis (2-methyl-8-quinolinolato) (2,4,6-triphenylphenolate) aluminum, bis (2-Methyl-8-quinolinolato) (2,4,6-trimethylphenolate) aluminum, bis (2-methyl-8-quinolinolato) (2,4,5,6-tetramethylphenolate) aluminum, bis ( 2-methyl-8-quinolinolato) (1-naphtholato) aluminum, bis (2-methyl-8-quinolinolato) (2-naphtholato) aluminum, bis (2,4-dimethyl-8-quinolinolato) (2-phenylphenolate) ) Aluminum, bis (2,4-dimethyl-8-quinolinolate) ) (3-phenylphenolate) aluminum, bis (2,4-dimethyl-8-quinolinolato) (4-phenylphenolate) aluminum, bis (2,4-dimethyl-8-quinolinolato) (3,5-dimethylphenol) Lat) aluminum, bis (2,4-dimethyl-8-quinolinolato) (3,5-di-t-butylphenolate) aluminum, bis (2-methyl-8-quinolinolato) aluminum-μ-oxo-bis (2 -Methyl-8-quinolinolato) aluminum, bis (2,4-dimethyl-8-quinolinolato) aluminum-μ-oxo-bis (2,4-dimethyl-8-quinolinolato) aluminum, bis (2-methyl-4-ethyl) -8-quinolinolato) aluminum-μ-oxo-bis (2-methyl-4-ethyl-8) Quinolinolato) aluminum, bis (2-methyl-4-methoxy-8-quinolinolato) aluminum-μ-oxo-bis (2-methyl-4-methoxy-8-quinolinolato) aluminum, bis (2-methyl-5-cyano- 8-quinolinolato) aluminum-μ-oxo-bis (2-methyl-5-cyano-8-quinolinolato) aluminum, bis (2-methyl-5-trifluoromethyl-8-quinolinolato) aluminum-μ-oxo-bis ( 2-methyl-5-trifluoromethyl-8-quinolinolato) aluminum, bis (10-hydroxybenzo [h] quinoline) beryllium and the like.

  The electron transport layer or the electron injection layer may further contain a substance capable of reducing the material forming the electron transport layer or the electron injection layer. As the reducing substance, various substances may be used as long as they have a certain reducing ability. For example, alkali metals, alkaline earth metals, rare earth metals, alkali metal oxides, alkali metal halides (for example, LiF, etc.), alkaline earth metal oxides, alkaline earth metal halides, rare earth metal oxides, rare earth metal halides, alkali metal organic complexes, alkaline earth metal organic complexes, and rare earth metal organics At least one selected from the group consisting of complexes can be suitably used.

  Preferred reducing substances include alkali metals such as Na (work function 2.36 eV), K (2.28 eV), Rb (2.16 eV) or Cs (1.95 eV), and Ca (2. 9eV), Sr (2.0 to 2.5 eV) or Ba (2.52 eV), and the like, and those having a work function of 2.9 eV or less are particularly preferable. Among these, a more preferable reducing substance is an alkali metal of K, Rb or Cs, more preferably Rb or Cs, and most preferably Cs. These alkali metals have particularly high reducing ability, and by adding a relatively small amount to the material forming the electron transport layer or the electron injection layer, the luminance of the organic EL element can be improved and the lifetime can be extended. Further, as a reducing substance having a work function of 2.9 eV or less, a combination of two or more alkali metals is also preferable. Particularly, a combination containing Cs, such as Cs and Na, Cs and K, Cs and Rb, or A combination of Cs, Na and K is preferred. By containing Cs, the reducing ability can be efficiently exhibited, and by adding to the material for forming the electron transport layer or the electron injection layer, the luminance of the organic EL element can be improved and the lifetime can be extended.

8). The cathode 108 of the organic EL element plays a role of injecting electrons into the light emitting layer 105 through the electron injection layer 107, the electron transport layer 106 and the light emission auxiliary layer 110.

  The material for forming the cathode 108 is not particularly limited as long as it can efficiently inject electrons into the organic layer, but the same material as that for forming the anode 102 can be used. Among them, metals such as tin, magnesium, indium, calcium, aluminum, silver, copper, nickel, chromium, gold, platinum, iron, zinc, lithium, sodium, potassium, cesium and magnesium or alloys thereof (magnesium-silver alloy) , Magnesium-indium alloys, aluminum-lithium alloys such as lithium fluoride / aluminum) are preferred. Lithium, sodium, potassium, cesium, calcium, magnesium, or alloys containing these low work function metals are effective for increasing the electron injection efficiency and improving device characteristics. However, these low work function metals are often often unstable in the atmosphere. In order to improve this point, for example, a method is known in which an organic layer is doped with a small amount of lithium, cesium or magnesium and a highly stable electrode is used. As other dopants, inorganic salts such as lithium fluoride, cesium fluoride, lithium oxide, and cesium oxide can also be used. However, it is not limited to these.

  Furthermore, for electrode protection, metals such as platinum, gold, silver, copper, iron, tin, aluminum and indium, or alloys using these metals, and inorganic materials such as silica, titania and silicon nitride, polyvinyl alcohol, vinyl chloride Lamination of hydrocarbon polymer compounds and the like is a preferred example. The method for producing these electrodes is not particularly limited as long as conduction can be achieved, such as resistance heating, electron beam, sputtering, ion plating, and coating.

9. Manufacturing method of organic EL element Each layer constituting the organic EL element is formed by using a deposition method, a resistance heating vapor deposition method, an electron beam vapor deposition method, a sputtering method, a molecular layering method, a printing method using an ink jet method, or the like. It can be formed by forming a thin film by a method such as a method, a casting method or a coating method. The thickness of each layer formed in this way is not particularly limited and can be appropriately set according to the properties of the material, but is usually in the range of 2 nm to 5000 nm. The film thickness can usually be measured with a crystal oscillation type film thickness measuring device or the like.

For example, when a thin film is formed using a vapor deposition method, the vapor deposition conditions vary depending on the type of material, the intended crystal structure and association structure of the film, and the like. Deposition conditions generally include boat heating temperature +50 to + 400 ° C., vacuum degree 10 ⁻⁶ to 10 ⁻³ Pa, deposition rate 0.01 to 50 nm / sec, substrate temperature −150 to + 300 ° C., film thickness 2 nm to 5 μm. It is preferable to set appropriately within the range.

  In addition, for example, in the case of an inkjet printing method, that is, a method of forming each layer of an organic EL element using an organic EL material-containing solution, a good solvent is selected for the organic EL material, and a uniform solution is prepared for use. It is also possible to prepare a dispersion using a poor solvent or a mixed solvent of a good solvent and a poor solvent. However, it is preferable to use a good solvent in order to suppress nozzle clogging of the inkjet head. For example, aromatic solvents, halogen solvents, ether solvents and the like are often used as good solvents, and alcohol solvents, ketone solvents, paraffin solvents are often used as poor solvents. Examples thereof include solvents and alkylbenzene derivatives having 4 or more carbon atoms. More specifically, examples of solvents that are often good solvents include aromatic solvents such as toluene, xylene, and mesitylene, halogen solvents such as chlorobenzene, and ether solvents such as diphenyl ether. Often used are alcohol solvents such as methanol, ethanol, propanol, butanol, pentanol, hexanol, heptanol, octanol, nonanol, decanol, etc., which are linear or branched alcohols having 1 to 20 carbon atoms, benzyl alcohol derivatives And alkylbenzene derivatives such as hydroxyalkylbenzene derivatives, linear or branched butylbenzene, dodecylbenzene, tetralin and cyclohexylbenzene. The amount of the solvent used can be appropriately adjusted in consideration of the amount and type of the organic EL material, the thickness of the organic thin film layer, and the like.

  Next, as an example of a method for producing an organic EL element, anode / hole injection layer / hole transport layer / light emitting layer composed of host material and dopant material / light emission auxiliary layer / electron transport layer / electron injection layer / cathode A method for manufacturing the organic EL element will be described. A thin film of an anode material is formed on a suitable substrate by vapor deposition or the like to produce an anode, and then a thin film of a hole injection layer and a hole transport layer is formed on the anode. A host material and a dopant material are co-deposited thereon to form a thin film to form a light emitting layer. A light emitting auxiliary layer, an electron transport layer and an electron injection layer are formed on the light emitting layer, and a thin film made of a cathode material is formed. The target organic EL device can be obtained by forming the cathode by vapor deposition or the like. In the production of the organic EL device described above, the production order is reversed, and the cathode, the electron injection layer, the electron transport layer, the light emission auxiliary layer, the light emission layer, the hole transport layer, the hole injection layer, and the anode are arranged in this order. It is also possible to produce it.

  When a DC voltage is applied to the organic EL device thus obtained, the anode may be applied with a positive polarity and the cathode with a negative polarity. When a voltage of about 2 to 40 V is applied, a transparent or translucent electrode is applied. Luminescence can be observed from the side (anode or cathode, and both). The organic EL element also emits light when a pulse current or an alternating current is applied. The alternating current waveform to be applied may be arbitrary.

10. Application Example of Organic EL Element The present invention can also be applied to a display device provided with an organic EL element or a lighting device provided with an organic EL element. The display device or lighting device including the organic EL element can be manufactured by a known method such as connecting the organic EL element according to the present embodiment and a known driving device, such as DC driving, pulse driving, or AC driving. It can drive using a well-known drive method suitably.

  Examples of the display device include a panel display such as a color flat panel display, and a flexible display such as a flexible color organic EL display (for example, JP-A-10-335066, JP-A-2003-321546, and JP-A-2003-321546). 2004-281086 publication etc.). Examples of the display method of the display include a matrix and / or segment method. Note that the matrix display and the segment display may coexist in the same panel.

  A matrix means a pixel in which pixels for display are two-dimensionally arranged such as a lattice or a mosaic, and displays a character or an image with a set of pixels. The shape and size of the pixel are determined by the application. For example, a square pixel with a side of 300 μm or less is usually used for displaying images and characters on a personal computer, monitor, TV, and a pixel with a side of mm order for a large display such as a display panel. become. In monochrome display, pixels of the same color may be arranged. However, in color display, red, green, and blue pixels are displayed side by side. In this case, there are typically a delta type and a stripe type. The matrix driving method may be either a line sequential driving method or an active matrix. The line-sequential driving has an advantage that the structure is simple. However, the active matrix may be superior in consideration of the operation characteristics, so that it is necessary to properly use it depending on the application.

  In the segment system (type), a pattern is formed so as to display predetermined information, and a predetermined region is caused to emit light. For example, the time and temperature display in a digital clock or a thermometer, the operation state display of an audio device or an electromagnetic cooker, the panel display of an automobile, etc.

  Examples of the illuminating device include an illuminating device such as indoor lighting, a backlight of a liquid crystal display device, and the like (for example, Japanese Patent Application Laid-Open Nos. 2003-257621, 2003-277741, and 2004-119211). Etc.) The backlight is used mainly for the purpose of improving the visibility of a display device that does not emit light, and is used for a liquid crystal display device, a clock, an audio device, an automobile panel, a display panel, a sign, and the like. In particular, as a backlight for liquid crystal display devices, especially personal computers for which thinning is an issue, considering that conventional methods are made of fluorescent lamps and light guide plates, it is difficult to reduce the thickness. The backlight using the organic EL element according to the embodiment is characterized by being thin and lightweight.

<Synthesis example of light auxiliary layer material>
Hereinafter, Formula (2-1) to Formula (2-5), Formula (2-21), Formula (2-41), Formula (2-61), Formula (2-62), Formula (2-85) , Formula (2-87), Formula (1-1), Formula (1-71), Formula (3-5), Formula (3-6), Formula (3-8), Formula (5-7), Synthesis examples of the compounds represented by formula (6-9) and formula (EAL-1) will be described. Compound (EAL-1) is a comparative compound.

<Synthesis Example of Compound (2-1)>

  Under a nitrogen atmosphere, 7,7-diphenyl-5,9-bis (trifluoromethanesulfonyloxy) -7H-benzo [c] fluorene (6.66 g) and 2-naphthyleneboronic acid (5.16 g) were added to tetrahydrofuran and isopropyl alcohol. Dissolve in a mixed solvent (100 ml, tetrahydrofuran / isopropyl alcohol = 1/4 (volume ratio)), add tetrakis (triphenylphosphine) palladium (0) (1.16 g), stir for 5 minutes, and then potassium phosphate (12.7 g) was added and refluxed for 4 hours. After the reaction, 50 ml of the solvent was removed. 100 ml of water was added and the precipitate was filtered. The precipitate was further washed with water and methanol to obtain a crude product of the compound (2-1). The crude product was subjected to column purification with silica gel (solvent: heptane / toluene = 3/1 (volume ratio)) and then purified by sublimation to obtain 5.0 g of the desired compound (2-1) (yield: 80.5%).

The structure of the compound (2-1) was confirmed by MS spectrum and NMR measurement.
¹ H-NMR (CDCl ₃ ): δ = 8.93 (d, 1H), 8.53 (d, 1H), 8.06 to 8.04 (m, 2H), 7.93 to 7.21 ( m, 28H).

<Synthesis Example of Compound (2-2)>

Under a nitrogen atmosphere, 5,9-dibromo-7,7-diphenyl-7H-benzo [c] fluorene (2.2 g), 1-naphthyleneboronic acid (1.6 g), tetrakis (triphenylphosphine) palladium (0) ( Pd (PPh ₃ ) ₄ ) (0.1 g), potassium phosphate (3.6 g) and toluene (21 ml) were placed in a flask and stirred for 5 minutes. Then, water (4 ml) was added and refluxed for 4 hours. After completion of heating, the reaction solution was cooled and water (10 ml) was added. The reaction mixture was extracted with toluene, dried over anhydrous sodium sulfate, the desiccant was removed, the solvent was distilled off under reduced pressure, and the resulting crude product was subjected to short column purification with silica gel (solvent: toluene). . Thereafter, recrystallization is performed with ethyl acetate, and further purification by sublimation is performed to obtain the target compound (2-2) “5,9-di (naphthalen-1-yl) -7,7-diphenyl-7H-benzo [c ] Fluorene "(0.8 g, yield: 31%) was obtained.

The structure of the compound (2-2) was confirmed by MS spectrum and NMR measurement.
¹ H-NMR (CDCl ₃ ): δ = 8.96 (d, 1H), 8.56 (d, 1H), 7.94-7.84 (m, 5H), 7.69-7.63 ( m, 4H), 7.57-7.26 (m, 15H), 7.20-7.17 (m, 6H).

<Synthesis Example of Compound (2-3)>

  Under a nitrogen atmosphere, 5,9-dibromo-7,7-diphenyl-7H-benzo [c] fluorene (5.26 g) and 4-biphenylboronic acid (4.36 g) were mixed with toluene and ethanol (50 ml, toluene). / Ethanol = 4/1 (volume ratio)), tetrakis (triphenylphosphine) palladium (0) (0.69 g) was added, and the mixture was stirred for 5 minutes. Reflux for hours. After completion of heating, the reaction mixture was cooled, the organic layer was separated, washed with saturated brine, and dried over anhydrous magnesium sulfate. After removing the desiccant and evaporating the solvent under reduced pressure, the solid obtained was subjected to column purification with silica gel (solvent: heptane / toluene = 3/1 (volume ratio)), followed by purification by sublimation. 3.9 g (yield: 58%) of the compound (2-3) was obtained.

The structure of the compound (2-3) was confirmed by MS spectrum and NMR measurement.
¹ H-NMR (CDCl ₃ ): δ = 8.91 (d, 1H), 8.49 (d, 1H), 8.11 (d, 1H), 7.79-7.77 (m, 2H) , 7.73-7.20 (m, 31H).

<Synthesis Example of Compound (2-4)>

Under a nitrogen atmosphere, 5,9-dibromo-7,7-diphenyl-7H-benzo [c] fluorene (2.2 g), 9-phenanthreneboronic acid (2.3 g), tetrakis (triphenylphosphine) palladium ( 0) (Pd (PPh ₃ ) ₄ ) (0.1 g), potassium phosphate (3.6 g) and toluene (21 ml) were placed in a flask and stirred for 5 minutes. Then, water (4 ml) was added and refluxed for 4 hours. After completion of the heating, the reaction solution was cooled and water (20 ml) was added. The reaction mixture was extracted with toluene, dried over anhydrous sodium sulfate, the desiccant was removed, the solvent was distilled off under reduced pressure, and the resulting crude product was subjected to column purification with silica gel (solvent: heptane / toluene = 3 / 1 (capacity ratio)). Furthermore, by sublimation purification, 1.6 g (yield) of the target compound (2-4) “5,9-di (phenanthrene-9-yl) -7,7-diphenyl-7H-benzo [c] fluorene”. : 53%).

The structure of the compound (2-4) was confirmed by MS spectrum and NMR measurement.
¹ H-NMR (CDCl ₃ ): δ = 8.99 (d, 1H), 8.80 to 8.76 (m, 3H), 8.72 (d, 1H), 8.61 (d, 1H) 7.97 (d, 1H), 7.92 to 7.87 (q, 2H), 7.77 to 7.60 (m, 13), 7.51 to 7.48 (m, 2H), 7 40 to 7.33 (m, 6H), 7.21 to 7.17 (m, 6H).

<Synthesis Example of Compound (2-5)>

  First, methanesulfonic acid (130 mL) was added to compound (2-5a) “5-methoxy-2- (4-methoxynaphthalen-1-yl) -benzoic acid methyl ester” (21.0 g) under a nitrogen atmosphere, The mixture was heated and stirred at 65 ° C for 1.5 hours. The reaction mixture was added to ice water, and the precipitated solid was separated by filtration and washed with methanol. The obtained solid (22.5 g) was purified by recrystallization (solvent: ethyl acetate) to obtain an intermediate compound (2-5c) (14.6 g) (yield 77%).

  Next, under a nitrogen atmosphere, a suspension of the intermediate compound (2-5c) (13.2 g) in THF (120 mL) was added to 2-bromobiphenyl (17.0 g), magnesium (1.77 g), and THF (150 mL). After adding a THF solution of 2-biphenylmagnesium bromide prepared at 0 ° C., the mixture was further heated and stirred at reflux temperature for 1.5 hours. Water was added to the reaction mixture, the target component was extracted with toluene, and the organic layer was concentrated to obtain a solid crude product (25.4 g) of the target component. The obtained solid was purified by silica gel column chromatography (developing solvent: toluene / ethyl acetate = 9/1 (volume ratio)) to obtain an intermediate compound (2-5e) (17.4 g) (yield) 86%).

  Next, concentrated sulfuric acid (0.1 mL) was added to a suspension of the intermediate compound (2-5e) (17.4 g) in acetic acid (230 mL) at room temperature under a nitrogen atmosphere, and further at 100 ° C. for 3 hours. Stir with heating. Water was added to the reaction mixture, and the precipitated solid was separated by filtration. The obtained solid was washed with methanol to obtain an intermediate compound (2-5f1) (16.2 g) (yield 97%).

  Next, a 1 mol / L boron tribromide / dichloromethane solution (100 mL) was added dropwise at 0 ° C. to a solution of the intermediate compound (2-5f1) (16.2 g) in dichloromethane (250 mL) under a nitrogen atmosphere. After that, the mixture was further stirred overnight at room temperature. Water was added to the reaction mixture, the target component was extracted with ethyl acetate, and the organic layer was concentrated to obtain a solid crude product of the target component. The obtained solid was washed with heptane to obtain an intermediate compound (2-5f2) (15.1 g) (yield 100%).

  Next, trifluoromethanesulfonic anhydride (32.2 g) was added dropwise at 0 ° C. to a pyridine (200 mL) solution of the intermediate compound (2-5f2) (15.1 g) in a nitrogen atmosphere, and then further added. Stir at room temperature overnight. Water was added to the reaction mixture, and the precipitated solid was separated by filtration. The obtained solid was purified by silica gel column chromatography (developing solvent: toluene) to obtain an intermediate compound (2-5f3) “5,9-bis (trifluoromethanesulfonyloxy) -7H-benzo [c] fluorene-7. -Spiro-9'-fluorene "(23.6 g) was obtained (yield 94%).

  Finally, under nitrogen atmosphere, intermediate compound (2-5f3) (6.63 g), 2-naphthyleneboronic acid (3.78 g), potassium phosphate (12.7 g), tetrahydrofuran (20 mL) and isopropyl alcohol (80 mL) To the mixed solution was added tetrakis (triphenylphosphine) palladium (0) (1.16 g), and the mixture was heated and stirred at reflux temperature for 7.5 hours. Water was added to the reaction mixture, the target component was extracted with toluene, and the organic layer was concentrated to obtain a solid crude product (8.90 g) of the target component. The obtained solid was purified by silica gel column chromatography (developing solvent: heptane / toluene = 2/1 (volume ratio)) and recrystallization (solvent: ethyl acetate) to obtain compound (2-5) (2.28 g). (Yield 37%).

The glass transition temperature (Tg) of the obtained compound was 164 ° C. Moreover, the structure of the compound (2-5) obtained by NMR measurement was confirmed.
¹ H-NMR (CDCl ₃ ): δ = 6.86 to 6.87 (m, 3H), 7.12 to 7.17 (m, 3H), 7.37 to 7.53 (m, 8H), 7.62-7.64 (dd, 1H), 7.76-7.93 (m, 12H), 8.02-8.04 (d, 1H), 8.58-8.60 (d, 1H) ), 8.99 to 9.01 (d, 1H).

<Synthesis Example of Compound (2-21)>

  First, an intermediate compound (2-21a) obtained by Suzuki coupling of 1-naphthaleneboronic acid and 2-bromo-5-chlorobenzoic acid methyl ester was synthesized. By reacting the obtained intermediate compound (2-21a) with lithiated 2-bromonaphthalene with n-butyllithium to obtain an intermediate compound (2-21b), and further cyclizing with sulfuric acid, The intermediate compound (2-21c) was obtained. The obtained intermediate compound (2-21c) was brominated with NBS to obtain an intermediate compound (2-21d) “5-bromo-9-chloro-7,7-di (naphthalen-2-yl)- 7H-benzo [c] fluorene "was obtained.

  Next, in a nitrogen atmosphere, the intermediate compound (2-21d) (3.82 g), 2-naphthaleneboronic acid (2.48 g), Pd (dba) 2 (0.38 g), tricyclohexylphosphine (0.28 g) ), Tripotassium phosphate (8.40 g), toluene (24 ml), ethanol (6 ml) and water (3 ml) were heated and stirred at reflux temperature for 6 hours. The reaction solution was cooled to room temperature, the deposited precipitate was collected by suction filtration, and the obtained precipitate was washed with water. Furthermore, after refine | purifying with activated carbon column chromatography (toluene), 1.78 g (yield 39%) of target compounds (2-21) were obtained by recrystallizing from a toluene / IPA = 1 mixed solvent.

<Synthesis Example of Compound (2-41)>

Under a nitrogen atmosphere, 5,9-dibromo-7,7-dimethyl-7H-benzo [c] fluorene (6.00 g), 2-naphthaleneboronic acid (5.65 g), potassium carbonate (6.19 g), tetrabutyl A mixed solution of ammonium bromide (TBAB) (0.96 g), Pd (PPh ₃ ) ₂ Cl ₂ (0.31 g), toluene (30 ml) and water (15 mL) was heated and stirred at reflux temperature for 3 hours. Water was added to the reaction mixture, and the target component was extracted with toluene, and then the organic layer was concentrated. The obtained solid was purified by silica gel column chromatography (developing solvent: heptane / toluene = 3/1 (volume ratio)) and further washed with ethyl acetate to obtain 1.60 g (yield) of compound (2-41). Rate 22%).

<Synthesis Example of Compound (2-61)>

  Under a nitrogen atmosphere, 5-bromo-7,7-diphenyl-7H-benzo [c] fluorene (2.3 g), bis (pinacolato) diboron (1.3 g), [1,1′-bis (diphenylphosphino) Ferrocene] dichloropalladium (II) (0.4 g), potassium acetate (3.0 g) and dimethyl sulfoxide (50 ml) were placed in a flask and heated at 80 ° C. for 5 hours. Thereafter, the temperature was returned to room temperature, and 5-bromo-7,7-diphenyl-7H-benzo [c] fluorene (1.8 g), bis (pinacolato) diboron (0.15 g), [1,1′-bis (diphenylphosphine). Fino) ferrocene] dichloropalladium (II) (0.15 g) was added and further heated at 80 ° C. for 12 hours. After completion, the reaction mixture was cooled and water (50 ml) was added. The reaction mixture was extracted with toluene, the solvent was distilled off under reduced pressure, and the resulting crude product was subjected to short column purification (solvent: toluene) with silica gel. Thereafter, purification was performed by silica gel column purification (solvent: toluene / heptane = 1/4 (volume ratio)). After removing the solvent with a vacuum pump, the product was further purified by sublimation to obtain 0.7 g (yield 20%) of the desired compound (2-61).

<Synthesis Example of Compound (2-62)>

  First, an intermediate compound (2-62a) obtained by Suzuki coupling of 1-naphthaleneboronic acid and 2-bromo-5-chlorobenzoic acid methyl ester is reacted with phenyllithium to obtain an intermediate compound (2 The intermediate compound (2-62c) “9-chloro-7,7-diphenyl-7H-benzo [c] fluorene” was obtained by further cyclization with sulfuric acid.

Next, in a nitrogen atmosphere, intermediate compound (2-62c) (3.0 g), bispinacolatodiboron (0.95 g), Pd (dba) ₂ (0.21 g), tricyclohexylphosphine (0.21 g) ), Tripotassium phosphate (4.74 g) and dimethoxyethane (15 ml) were heated and stirred at reflux temperature for 2.5 hours. After confirming that bispinacolatodiboron was consumed, xylene (30.0 ml) was added and dimethoxyethane was removed while refluxing. Furthermore, after heating and stirring at reflux temperature for 9 hours, the reaction solution was cooled to room temperature, methanol was added, the deposited precipitate was collected by suction filtration, and the obtained precipitate was washed with water. Furthermore, after refine | purifying with a silica gel short pass column (chlorobenzene), 0.79g (yield 37%) of target compounds (2-62) were obtained by recrystallizing from toluene.

<Synthesis Example of Compound (2-85)>

  First, 7,7-diphenyl-7H-benzo [c] fluorene is brominated with NBS, and the resulting intermediate compound (2-85a) is reacted with bispinacolatodiboron to form an intermediate boronic ester. (2-85b) “2- (7,7-dimethyl-7H-benzo [c] fluoren-5-yl) -4,4,5,5-tetramethyl-1,3,2-dioxaborolane” was obtained. .

  Next, under a nitrogen atmosphere, intermediate compound (2-85b) (4.00 g), 4,4′-dibromo-1,1′-biphenyl (1.69 g), Pd-132 (0.15 g), phosphorus A mixed solution of tripotassium acid (2.87 g), TBAB (0.17 g), toluene (40 ml) and water (5 ml) was stirred with heating at reflux temperature for 4 hours and a half. The reaction solution was cooled to room temperature, the deposited precipitate was collected by suction filtration, and the obtained precipitate was washed with water and methanol. Furthermore, recrystallization from orthodichlorobenzene gave 0.52 g (yield 15%) of the target compound (2-85).

<Synthesis Example of Compound (2-87)>

  Under a nitrogen atmosphere, the intermediate compound (2-85b) (4.00 g), 2,6-dibromonaphthalene (1.40 g), Pd-132 (0.07 g), tripotassium phosphate (2.61 g), A mixed solution of toluene (40 ml), isopropanol (10 ml) and water (5 ml) was stirred with heating at reflux temperature for 4 hours and a half. The reaction solution was cooled to room temperature, the deposited precipitate was collected by suction filtration, and the obtained precipitate was washed with water and methanol. After reprecipitation from a chlorobenzene / ethyl acetate mixed solvent, 1.43 g (yield 48%) of the target compound (2-87) was obtained by recrystallization from orthodichlorobenzene.

<Synthesis Example of Compound (1-1)>

Under a nitrogen atmosphere, 2,7-dibromo-9,9-diphenyl-9H-fluorene (3.00 g), 2-naphthaleneboronic acid (2.38 g), potassium carbonate (2.61 g), TBAB (0.20 g) , Pd (PPh ₃ ) ₂ Cl ₂ (0.13 g), toluene (30 ml) and water (15 mL) were heated and stirred at reflux temperature for 2 hours. Water was added to the reaction mixture, and the target component was extracted with toluene, and then the organic layer was concentrated. Crystals precipitated during the concentration were collected by suction filtration and recrystallized from chlorobenzene to obtain 0.57 g (yield 16%) of the target compound (1-1).

株式会社オ−ジェック製の市販品（製品番号LT-E411 BSBF）を使用した。<Synthesis Example of Compound (1-71)>

A commercially available product (Product No. LT-E411 BSBF) manufactured by OJEC Co., Ltd. was used.

特開２００９−１８４９９３号公報に記載された合成法で合成した。<Synthesis Example of Compound (3-5)>

It was synthesized by the synthesis method described in JP2009-184993A.

特開２００９−１８４９９３号公報に記載された合成法で合成した。<Synthesis Example of Compound (3-6)>

It was synthesized by the synthesis method described in JP2009-184993A.

特開２００９−１８４９９３号公報に記載された合成法で合成した。<Synthesis Example of Compound (3-8)>

It was synthesized by the synthesis method described in JP2009-184993A.

<Synthesis Example of Compound (5-7)>

  First, methyl 1-hydroxy-2-naphthoate (25 g) was dissolved in dichloromethane (200 ml) under a nitrogen atmosphere. After adding pyridine (15 ml), the mixture was cooled to −20 ° C., and trifluoromethanesulfonic anhydride (44 g) was added. After stirring at room temperature for 10 hours, the reaction mixture was added to water and precipitated with dichloromethane. The extract was concentrated and purified by a silica gel column (toluene / heptane = 2/1 (volume ratio)). The solvent was removed to obtain 28 g (yield 67%) of intermediate compound (5-7a).

  Next, in a nitrogen atmosphere, the intermediate compound (5-7a) (8.7 g) and 1-naphthyleneboronic acid (5.0 g) were mixed with toluene and water (100 ml, toluene / water = 1/1 (volume ratio). )), Tetrakis (triphenylphosphine) palladium (0) (1.0 g) and potassium phosphate (14.5 g) were added and refluxed for 6 hours. After the reaction, water was removed and the solution was concentrated. The crude product was subjected to column purification with silica gel (solvent: ethyl acetate / toluene = 1/10 (volume ratio)) to obtain 5.7 g (yield: 70%) of an oily intermediate compound (5-7b). It was.

  Next, the intermediate compound (5-7b) (5.7 g) was dissolved in tetrahydrofuran (100 ml) under a nitrogen atmosphere and cooled to -70 ° C. A phenyl lithium / dibutyl ether solution (2.0 mol / ml) (45 ml) was added, and the mixture was stirred at room temperature for 10 hours. After the reaction, an aqueous ammonium chloride solution was added to quench excess phenyllithium. The crude product obtained by collecting and concentrating the organic layer was subjected to column purification with silica gel (solvent: toluene) to obtain 5.1 g (yield 67%) of an oily intermediate compound (5-7c).

  Next, the intermediate compound (5-7c) (5.1 g) was dissolved in acetic acid (50 ml), a few drops of concentrated sulfuric acid was added, and the mixture was stirred at 80 ° C. for 1 hour. The crude product precipitated by adding water was subjected to column purification with silica gel (solvent: toluene) to obtain 3.6 g (yield 73%) of the intermediate compound (5-7d) as a white solid.

  Next, the intermediate compound (5-7d) (3.6 g) was dissolved in a mixed solvent of acetic acid / dichloromethane (100 ml, acetic acid / dichloromethane = 1/1 (volume ratio)) under a nitrogen atmosphere, and zinc chloride (3 0.1 g) was added and heated at 55 ° C. A benzyltrimethylammonium tribromide / dichloromethane solution (10.6 g / 25 ml) was dropped from the dropping funnel, and the mixture was stirred for 5 hours while being heated to 55 ° C. Water was added to the reaction mixture and extracted with chloroform. The crude product from which the solvent was removed under reduced pressure was subjected to column purification with silica gel (solvent: toluene / heptane = 1/1 (volume ratio)) to obtain 2.8 g (yield) of the intermediate compound (5-7e) as a pale yellow solid. Rate 52%).

  Finally, in a nitrogen atmosphere, intermediate compound (5-7e) (2.8 g) and phenylboronic acid (1.3 g) were mixed in toluene / ethanol (50 ml, toluene / ethanol = 4/1 (volume ratio)). ), Tetrakis (triphenylphosphine) palladium (0) (1.0 g) and an aqueous sodium carbonate solution (4.1 g / 20 ml) were added, and the mixture was refluxed for 6 hours. After the reaction, water was added to dissolve the salt, the organic layer was collected and the solution was concentrated. The crude product was subjected to column purification with silica gel (solvent: toluene). After further toluene recrystallization, purification by sublimation was performed to obtain 0.58 g (yield) of the target compound (5-7) “5,7,7,9-tetraphenyl-7H-dibenzo [c, g] fluorene”. Rate 20%).

<Synthesis Example of Compound (6-9)>

  First, in a nitrogen atmosphere, intermediate compound (5-7a) (8.7 g) and 2-naphthyleneboronic acid (5.0 g) were mixed in a toluene / ethanol / water mixed solvent (50 ml / 15 ml / 15 ml (volume ratio)). After dissolution, tetrakis (triphenylphosphine) palladium (0) (1.0 g) and potassium phosphate (14.5 g) were added and refluxed for 6 hours. After the reaction, water was removed and the solution was concentrated. The crude product was subjected to column purification with silica gel (solvent: heptane / toluene = 1/1 (volume ratio)) to obtain 8.0 g (yield 99%) of an oily intermediate compound (6-9a).

  Next, the intermediate compound (6-9a) (8.0 g) was dissolved in tetrahydrofuran (80 ml) under a nitrogen atmosphere and cooled to -70 ° C. A phenyl lithium / dibutyl ether solution (2.0 mol / ml) (38 ml) was added, and the mixture was stirred at room temperature for 10 hours. After the reaction, an aqueous ammonium chloride solution was added to quench excess phenyllithium. The crude product obtained by collecting and concentrating the organic layer was subjected to column purification with silica gel (solvent: toluene) to remove the solvent. 9.3 g (yield 96%) of the intermediate compound (6-9b) was obtained as a white solid.

  Next, the intermediate compound (6-9b) (9.3 g) was dissolved in acetic acid (50 ml), a few drops of concentrated sulfuric acid were added, and the mixture was stirred at 80 ° C. for 1 hour. Water was added, and the precipitated solid was washed with an aqueous sodium hydrogen carbonate solution, water, and methanol to obtain 8.8 g (yield 99%) of the intermediate compound (6-9c) as a white solid.

  Next, the intermediate compound (6-9c) (3.3 g) was dissolved in a mixed solvent of acetic acid / chloroform (100 ml, acetic acid / chloroform = 2/3 (volume ratio)) under a nitrogen atmosphere, and zinc chloride (1 .3 g) was added and cooled to -30 ° C. After adding benzyltrimethylammonium tribromide (3.4 g), the mixture was stirred at room temperature for 2 hours. Water was added to the reaction mixture and extracted with chloroform. The crude product from which the solvent was removed under reduced pressure was subjected to column purification using silica gel (solvent: toluene) to obtain 3.5 g (yield 92%) of the intermediate compound (6-9d) as a pale yellow solid.

  Finally, an intermediate compound (6-9d) (2.7 g) and 2-naphthylboronic acid (1.0 g) were mixed in a toluene / ethanol mixed solvent (50 ml, toluene / ethanol = 4/1 (volume) under a nitrogen atmosphere. Ratio)), tetrakis (triphenylphosphine) palladium (0) (0.1 g) and aqueous sodium carbonate solution (2.3 g / 10 ml) were added, and the mixture was refluxed for 6 hours. After the reaction, water was added to dissolve the salt, the organic layer was collected and the solution was concentrated. The crude product was subjected to column purification with silica gel (solvent: toluene / heptane = 1/4 (volume ratio)). After further recrystallization of toluene, purification by sublimation yielded 1.0 g (yield 33%) of the desired compound (6-9).

国際公開２０１０／０７４０８７号に記載された合成法で合成した。<Synthesis Example of Comparative Compound (EAL-1)>

It was synthesized by the synthesis method described in International Publication 2010/074087.

<Example of host material synthesis>
Hereinafter, synthesis examples of the compounds represented by Formula (BH-1) to Formula (BH-5) will be described.

<Synthesis Example of Compound (BH-1)>

  The compound represented by the formula (BH-1) is Compound 1 (see page 4 of the publication) described in Korean Patent Publication No. 10-2010-0007552 (published on January 22, 2010), It is a known compound. The compound represented by the formula (BH-1) was synthesized with reference to the synthesis method described in the publication.

<Synthesis Example of Compound (BH-2)>

  The compound represented by the formula (BH-2) is a compound H1 (see page 10 of the publication) described in International Publication No. 2007/065548 (published on June 14, 2007), and is a known compound It is. The compound represented by the formula (BH-2) was synthesized with reference to the synthesis method described in the publication.

<Synthesis Example of Compound (BH-3)>

First, in a nitrogen atmosphere, naphthalene-2,7-diyl bis (trifluoromethanesulfonate) (31.8 g), 2-naphthaleneboronic acid (12.9 g), tetrakis (triphenylphosphine) palladium (0) (Pd ( PPh ₃ ) ₄ ) (1.73 g), potassium phosphate (31.8 g) and a mixed solvent of tetrahydrofuran (THF) and isopropyl alcohol (IPA) (300 ml, THF / IPA = 4/1 (volume ratio)) Placed in flask and refluxed for 5 hours. The reaction liquid was cooled after completion | finish of a heating, water was added, and the target component was extracted with toluene. Further, the crude product obtained by concentrating the organic layer under reduced pressure was subjected to column purification with silica gel (solvent: heptane), and [2,2′-binaphthalene] -7-yl trifluoromethanesulfonate, which is an intermediate compound, was obtained. 4 g (yield: 44%) was obtained.

Next, [2,2′-binaphthalene] -7-yl trifluoromethanesulfonate (10 g), (10-phenylanthracen-9-yl) boronic acid (7.4 g), tetrakis (triphenylphosphine) under nitrogen atmosphere ) Palladium (0) (0.57 g, Pd (PPh ₃ ) ₄ ), potassium phosphate (10.55 g) and a mixed solvent of toluene and ethanol (100 ml, toluene / ethanol = 4/1 (volume ratio)) The flask was stirred for 5 minutes. Thereafter, 10 ml of water was added and refluxed for 3 hours. After the heating, the reaction solution was cooled, 60 ml of methanol was added, and the precipitate was filtered. The precipitate was further washed with methanol and water to obtain a crude product of the compound represented by the target formula (BH-3). The crude product was subjected to short column purification with silica gel (solvent: toluene), then washed with a mixed solvent of methanol and ethyl acetate (methanol / ethyl acetate = 4/1 (volume ratio)), and recrystallized with toluene. Then, after further purification by sublimation, 6.6 g of 9-([2,2′-binaphthalene] -7-yl) -10-phenylanthracene which is the target (BH-3) compound (yield: 53%) )

The structure of the target compound (BH-3) was confirmed by MS spectrum and NMR measurement.
¹ H-NMR (CDCl ₃ ): δ = 8.24 (s, 1H), 8.22 (s, 1H), 8.15-8.08 (q, 2H), 8.08 (s, 1H) 8.02 to 7.89 (m, 5H), 7.78 to 7.73 (m, 4H), 7.65 to 7.50 (m, 8H), 7.37 to 7.31 (m, 4H).

The glass transition temperature (Tg) of the target compound (BH-3) was 116.0 ° C.
[Measurement equipment: Diamond DSC (manufactured by PERKIN-ELMER); Measurement conditions: Cooling rate 200 ° C / Min.

式（ＢＨ−４）で表される化合物は、Luminescence Technology Corp.社から市販されているもの（製品名：LT-N473 m-Bpye、製品情報におけるＴｇ＝９７℃）を使用した。<Synthesis Example of Compound (BH-4)>

The compound represented by the formula (BH-4) was commercially available from Luminescence Technology Corp. (product name: LT-N473 m-Bpye, Tg = 97 ° C. in product information).

特開２０１２−１０４８０６号公報に記載された合成法で合成した。<Synthesis Example of Compound (BH-5)>

The compound was synthesized by the synthesis method described in JP2012-104806A.

<Synthesis example of dopant material>
Hereinafter, synthesis examples of the compounds represented by Formula (BD-1) to Formula (BD-8) will be described.

<Synthesis Example of Compound (BD-1)>

  Under a nitrogen atmosphere, 5,9-dibromo-7,7-dimethyl-7H-benzo [C] fluorene (9.5 g) and aniline (4.5 g) are dissolved in dehydrated toluene (80 ml) and bis (dibenzylideneacetone). ) Palladium (140 mg), sodium t-butoxide (7.0 g), and tris (t-butyl) phosphine (0.15 g) were added and heated at 50 ° C. for 2 hours. After the reaction, 1-bromo-4- (trimethylsilyl) benzene (11 g), palladium acetate (27 mg) and sodium t-butoxide (7.0 g) were added, and the mixture was heated at 80 ° C. for 4 hours. 100 ml of water was added, and the organic layer was washed with water using a separatory funnel. After removing the aqueous layer, the organic layer was collected and concentrated by a rotary evaporator to obtain a crude product. The crude product was subjected to column purification with silica gel (solvent: heptane / toluene = 5/1 (volume ratio)) and then purified by sublimation to obtain 3.1 g of compound (BD-1) (yield 18%). Obtained.

The structure of the compound (BD-1) was confirmed by MS spectrum and NMR measurement.
¹ H-NMR (CDCl ₃ ): δ = 8.68 (d, 1H), 8.15 (d, 1H), 8.05 (d, 1H), 7.56 (t, 1H, J = 8 Hz) 7.45-6.94 (m, 32H), 1.41 (s, 6H), 0.27 (s, 9H), 0.22 (s, 9H).

<Synthesis Example of Compound (BD-2)>

  Under a nitrogen atmosphere, 5,9-dibromo-7,7-dimethyl-7H-benzo [C] fluorene (8.0 g) and p-methylaniline hydrochloride (5.7 g) were dissolved in dehydrated toluene (200 ml), Bis (dibenzylideneacetone) palladium (115 mg), sodium t-butoxide (15 g), and 4- (dimethylamino) phenyl) bis t-butylphosphine (0.160 g) were added and heated at 80 ° C. for 2 hours. After the reaction, 1-bromo-4- (trimethylsilyl) benzene (10 g) was added and heated at 80 ° C. for 4 hours. 100 ml of water was added thereto, and the organic layer was washed with water using a separatory funnel. After removing the aqueous layer, the organic layer was collected and concentrated by a rotary evaporator to obtain a crude product. The crude product was subjected to column purification with alumina (solvent: heptane / toluene = 5/1 (volume ratio)) and then sublimation purification to obtain 6.9 g of compound (BD-2) (yield 46 %).

The structure of the compound (BD-2) was confirmed by NMR measurement.
¹ H-NMR (Toluene-d8): δ = 8.67 (d, 1H), 8.30 (d, 1H), 8.00 (d, 1H), 7.52 (t, 1H, J = 8 Hz) ), 7.42-6.83 (m, 20H), 2.13 (s, 3H), 2.06 (s, 3H), 1.16 (s, 6H), 0.24 (s, 9H) , 0.20 (s, 9H).

<Synthesis Example of Compound (BD-3)>

  Under an argon atmosphere, 5,9-diiodo-7,7-dimethyl-7H-benzo [C] fluorene (6.1 g) and aniline (2.3 g) were dissolved in dehydrated xylene (100 ml) and palladium bis (dibenzylidene). ) (0.12 g), sodium t-butoxide (7.2 g) and (4- (dimethylamino) phenyl) di-t-butylphosphine (0.16 g) were added and heated at 70 ° C. for 2 hours. 1-Bromo-naphthalene (5.2 g) was further added thereto and heated at 100 ° C. for 3 hours. After cooling to room temperature, 100 ml of water was added, and then the organic layer was washed with water using a separatory funnel. After removing the aqueous layer, the organic layer was collected and concentrated by a rotary evaporator to obtain a crude product. The crude product was subjected to column purification with alumina (solvent: toluene) to remove the coloring component, and further subjected to column purification with silica gel (solvent: toluene / heptane = 1/3 (volume ratio)). Furthermore, after recrystallizing with toluene / heptane, this was purified by sublimation to obtain 1.9 g of compound (BD-3) (yield 23%).

The structure of the compound (BD-3) was confirmed by MS spectrum and NMR measurement.
¹ H-NMR (CDCl ₃ ): δ = 8.62 (d, 1H), 8.14 (d, 1H), 8.07 (d, 1H), 7.96 (d, 1H), 7.88 (T, 1H), 7.77 (d, 1H), 7.66 (d, 1H), 7.52-6.73 (m, 25H), 1.27 (s, 6H).

特開２０１１−３７８３７号公報に記載された合成法で合成した。<Synthesis Example of Compound (BD-4)>

The compound was synthesized by the synthesis method described in JP2011-37837A.

特開２０１３−０８０９６１号公報に記載された合成法で合成した。<Synthesis Example of Compound (BD-5)>

It was synthesized by the synthesis method described in JP2013-080961A.

米国出願公開２０１０−０１４１１２４号に記載された合成法で合成した。<Synthesis Example of Compound (BD-6)>

It was synthesized by the synthesis method described in US Application Publication No. 2010-0141124.

国際公開２００４／０４４０８８号に記載された合成法で合成した。<Synthesis Example of Compound (BD-7)>

It was synthesized by the synthesis method described in International Publication No. 2004/044088.

国際公開２００２／０２０４５９号に記載された合成法で合成した。<Synthesis Example of Compound (BD-8)>

The compound was synthesized by the synthesis method described in International Publication No. 2002/020659.

<Synthesis example of electron transport material>
Hereinafter, synthesis examples of the compounds represented by formula (ETL-1) and formula (ETL-6) will be described.

<Synthesis Example of Compound (ETL-1)>

  First, 2-chloroanthracene (5.00 g), phenylboronic acid (4.3 g), tris (dibenzylideneacetone) dipalladium (0) (538 mg), tricyclohexylphosphine (494 mg), tripotassium phosphate (9. 98 g) and toluene (75 ml) were placed in a flask and stirred at reflux temperature for 2 hours under an argon atmosphere. After completion of the heating, 1.5 liters of toluene was added to the reaction solution, cooled to room temperature and filtered, and the filtrate was purified by silica gel column chromatography (mobile phase: toluene) using toluene as a moving bed. The solvent was distilled off under reduced pressure, and the concentrate was recrystallized from toluene to obtain 2-phenylanthracene (5.0 g).

  Next, 2-phenylanthracene (3.32 g) was dissolved in 400 ml of dichloromethane in a flask under a nitrogen atmosphere. A solution prepared by dissolving 5.00 g of bromine in 30 ml of carbon tetrachloride was added dropwise over 15 minutes. After completion of the dropping, the mixture was stirred for 2 hours at room temperature, and the reaction was stopped with an aqueous sodium thiosulfate solution. The organic layer was extracted with a separatory funnel and concentrated with an evaporator. The concentrate was recrystallized from toluene (50 ml) to obtain 9,10-dibromo-2-phenylanthracene (4.4 g).

  Next, 9,10-dibromo-2-phenylanthracene (10.0 g), bis (pinacolato) diboron (14.8 g), bis (dibenzylideneacetone) palladium (0) (838 mg), tricyclohexylphosphine (1. 02 g), potassium acetate (7.15 g) and 1,4-dioxane (50 ml) were placed in a flask and stirred at reflux temperature for 8 hours under an argon atmosphere. After heating, toluene was added to the reaction solution, cooled to room temperature and filtered, and the filtrate was concentrated by an evaporator. The concentrate was purified by silica gel column chromatography using toluene as the moving bed, then recrystallized with a tetrahydrofuran / heptane mixed solution, and 9,10-bis (4,4,5,5-tetramethyl-1,3). , 2-Dioxaborolanyl) -2-phenylanthracene (8.3 g) was obtained.

  Finally, 9,10-bis (4,4,5,5-tetramethyl-1,3,2-dioxaborolanyl) -2-phenylanthracene (0.80 g), 5-bromo-2,2 '-Bipyridine (0.83 g), tris (dibenzylideneacetone) dipalladium (0) (88 mg), tricyclohexylphosphine (81 mg), tripotassium phosphate (1.36 g), toluene (35 ml) were placed in a flask. The mixture was stirred at reflux temperature for 27 and a half hours under an argon atmosphere. After completion of the heating, the reaction solution was cooled to room temperature and pure water was added to extract the organic layer. The organic layer was concentrated by an evaporator, and the concentrate was purified by activated alumina column chromatography using toluene as a moving bed. Recrystallization was performed in a chloroform / ethyl acetate mixed solvent to obtain a compound (ETL-1) “9,10-bis (2,2′-bipyridin-5-yl) -2-phenylanthracene” (198 mg). .

The structure of the compound obtained by NMR measurement was confirmed.
¹ H-NMR (CDCl ₃ ): δ = 7.3 (t, 1H), 7.4 (m, 6H), 7.6 (d, 2H), 7.7 (m, 3H), 7.8 (D, 1H), 7.9 (m, 3H), 8.0 (m, 2H), 8.6 (d, 2H), 8.7 (d, 2H), 8.8 (m, 2H) 8.9 (m, 2H).

<Synthesis Example of Compound (ETL-2)>

  9,10-bis (4,4,5,5-tetramethyl-1,3,2-dioxaborolanyl) -2-phenylanthracene (5.0 g), 4- (2-pyridyl) bromobenzene ( 5.0 g), tetrakis (triphenylphosphine) palladium (0) (0.57 g), toluene (20 ml), ethanol (7 ml), aqueous potassium carbonate (potassium carbonate 4.2 g-water 7 ml) were placed in a flask. The mixture was stirred at reflux temperature for 14.5 hours under an argon atmosphere. After completion of heating, the reaction solution was cooled to room temperature and filtered. The obtained crude product was washed with water and methanol and then recrystallized with chlorobenzene to give the compound (ETL-2) “9,10-bis (4- (2-pyridyl) phenyl) -2-phenylanthracene”. (3.5 g) was obtained. The glass transition temperature (Tg) of the obtained compound was 134 ° C.

The structure of the compound obtained by NMR measurement was confirmed.
¹ H-NMR (CDCl ₃ ): δ = 8.8 (d, 2H), 8.3 (d, 4H), 8.0 to 7.7 (m, 8H), 7.6 to 7.4 ( m, 5H), 7.4 (d, 2H) 7.4 to 7.3 (m, 7H).

国際公開２０１２／０６０３７４号に記載された合成法で合成した。<Synthesis Example of Compound (ETL-3)>

It was synthesized by the synthesis method described in International Publication 2012/060374.

国際公開２０１０／１３７６７８号に記載された合成法で合成した。<Synthesis Example of Compound (ETL-4)>

It was synthesized by the synthesis method described in International Publication No. 2010/137678.

国際公開２００３／０６０９５６号に記載された合成法で合成した。<Synthesis Example of Compound (ETL-5)>

It was synthesized by the synthesis method described in International Publication No. 2003/060956.

国際公開２００４／０８０９７５号に記載された合成法で合成した。<Synthesis Example of Compound (ETL-6)>

It was synthesized by the synthesis method described in International Publication No. 2004/080975.

  By appropriately selecting the raw material compounds, other fluorene compounds, benzofluorene compounds, dibenzofluorene compounds, indenotriphenylene compounds, and indenopyrene compounds can be synthesized by a method according to the above synthesis example.

<Characteristics when used in electroluminescent devices>
Hereinafter, in order to describe the present invention in more detail, examples of the organic EL device using the compound of the present invention are shown, but the present invention is not limited thereto.

Organic EL elements according to Examples 1 to 11, Examples 12 to 31 and Comparative Examples 1 to 6 were produced, and voltage (V), emission wavelength (nm), and CIE color, which are characteristics at 1000 cd / m ² emission, respectively. The degree (x, y) and the external quantum efficiency (%) were measured, and then the time (h) for maintaining the luminance of 80% (800 cd / m ² ) or more of the initial luminance was measured. In some examples, the time (h) for maintaining a luminance of 90% (900 cd / m ² ) or more of the initial luminance was measured.

  Note that the quantum efficiency of a light-emitting element includes an internal quantum efficiency and an external quantum efficiency. The ratio of external energy injected as electrons (or holes) into the light-emitting layer of the light-emitting element is converted into photons purely. What is shown is the internal quantum efficiency. On the other hand, the external quantum efficiency is calculated based on the amount of photons emitted to the outside of the light emitting element, and some of the photons generated in the light emitting layer are absorbed inside the light emitting element. The external quantum efficiency is lower than the internal quantum efficiency because it is continuously reflected and is not emitted outside the light emitting element.

The external quantum efficiency is measured as follows. A voltage / current generator R6144 manufactured by Advantest Corporation was used to apply a voltage at which the luminance of the element was 1000 cd / m ² to cause the element to emit light. Using a spectral radiance meter SR-3AR manufactured by TOPCON, the spectral radiance in the visible light region was measured from the direction perpendicular to the light emitting surface. Assuming that the light emitting surface is a completely diffusing surface, the value obtained by dividing the measured spectral radiance value of each wavelength component by the wavelength energy and multiplying by π is the number of photons at each wavelength. Next, the number of photons in the entire wavelength region observed was integrated to obtain the total number of photons emitted from the device. The value obtained by dividing the applied current value by the elementary charge is the number of carriers injected into the device, and the number obtained by dividing the total number of photons emitted from the device by the number of carriers injected into the device is the external quantum efficiency.

  Table 1 below shows the material configuration of each layer in the organic EL elements according to Examples 1 to 11 and the EL characteristic data. In addition, Table 2 below shows the material configuration of each layer and EL characteristic data in the produced organic EL elements according to Examples 12 to 31 and Comparative Examples 1 to 6.

In Table 1, “HI” (hole injection layer material) is N ⁴ , N ^{4 ′} -diphenyl-N ⁴ , N ^{4 ′} -bis (9-phenyl-9H-carbazol-3-yl)-[1,1 '-Biphenyl] -4,4'-diamine, “HT” (hole transport layer material) is N-([1,1′-biphenyl] -4-yl) -9,9-dimethyl-N- (4 -(9-phenyl-9H-carbazol-3-yl) phenyl) -9H-fluoren-2-amine. The chemical structure is shown below.

<Example 1>
<Element Using Compound (2-1) for Light Emitting Auxiliary Layer>
A glass substrate of 26 mm × 28 mm × 0.7 mm (manufactured by Optoscience Co., Ltd.) obtained by polishing ITO deposited to a thickness of 180 nm by sputtering to 150 nm was used as a transparent support substrate. This transparent support substrate is fixed to a substrate holder of a commercially available vapor deposition apparatus (manufactured by Showa Vacuum Co., Ltd.), and a molybdenum vapor deposition boat, HT (hole transport layer material) containing HI (hole injection layer material). Molybdenum vapor deposition boat, molybdenum vapor deposition boat containing BH-1, molybdenum vapor deposition boat containing BD-1, molybdenum vapor deposition boat containing compound (2-1), ETL-1 A molybdenum deposition boat containing Li, a molybdenum deposition boat containing LiF (electron injection layer material), and a molybdenum deposition boat containing Al (cathode material) were mounted.

The following layers were sequentially formed on the ITO film of the transparent support substrate. Depressurize the vacuum chamber to 5 × 10 ⁻⁴ Pa, and first heat the vapor deposition boat containing HI (hole injection layer material) to form a hole injection layer by vapor deposition to a film thickness of 40 nm. Subsequently, the vapor deposition boat containing HT (hole transport layer material) was heated and vapor-deposited to a film thickness of 30 nm to form a hole transport layer. Next, the vapor deposition boat containing BH-1 and the vapor deposition boat containing BD-1 were heated at the same time to form a light emitting layer by vapor deposition to a film thickness of 30 nm. The deposition rate was adjusted so that the weight ratio of BH-1 to BD-1 was approximately 95: 5. Next, the evaporation boat containing the compound (2-1) was heated and evaporated to a film thickness of 20 nm to form a light emission auxiliary layer. Next, the evaporation boat containing ETL-1 was heated and evaporated to a thickness of 10 nm to form an electron transport layer. Further, an evaporation boat containing LiF (electron injection layer material) was heated and evaporated to a film thickness of 1 nm to form an electron injection layer. The above deposition rate was 0.01-1 nm / sec.

  Thereafter, a vapor deposition boat containing Al (cathode material) was heated and vapor-deposited to a film thickness of 100 nm to form a cathode. At this time, the cathode was formed so that the vapor deposition rate was 0.1 to 10 nm to obtain an organic electroluminescent element.

The characteristics at the time of light emission of 1000 cd / m ² were measured by applying a direct current voltage using the ITO electrode as the anode and the Al electrode as the cathode. ) Blue light emission was obtained. The driving voltage was 4.90 V and the external quantum efficiency was 5.61%. The time for maintaining the luminance of 80% (800 cd / m ² ) or more of the initial luminance was 400 hours.

<Example 2>
<Element Using Compound (2-1) for Light Emitting Auxiliary Layer>
An organic EL device was obtained by the method according to Example 1 except that ETL-1 as the electron transport layer material was changed to ETL-2. When direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 455 nm and CIE chromaticity (x, y) = (0.140, 0.120) was obtained. The driving voltage was 4.54 V and the external quantum efficiency was 5.90%. Further, the time for maintaining the luminance of 80% or more of the initial luminance was 356 hours.

<Example 3>
<Element Using Compound (2-2) for Light Emitting Auxiliary Layer>
An organic EL device was obtained by the method according to Example 1 except that the compound (2-1) as the light emitting auxiliary layer material was changed to the compound (2-2). When direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 455 nm and CIE chromaticity (x, y) = (0.140, 0.120) was obtained. The driving voltage was 6.71 V and the external quantum efficiency was 3.82%. Further, the time for maintaining the luminance of 80% or more of the initial luminance was 554 hours.

<Example 4>
<Element using Compound (2-3) for Light Emitting Auxiliary Layer>
An organic EL device was obtained by the method according to Example 1 except that the compound (2-1) as the light emitting auxiliary layer material was changed to the compound (2-3). When direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 455 nm and CIE chromaticity (x, y) = (0.140, 0.120) was obtained. The driving voltage was 5.17 V and the external quantum efficiency was 5.55%. Further, the time for maintaining the luminance of 80% or more of the initial luminance was 407 hours.

<Example 5>
<Element using Compound (2-4) for Light Emitting Auxiliary Layer>
An organic EL device was obtained by the method according to Example 1 except that the compound (2-1) as the light emitting auxiliary layer material was changed to the compound (2-4). When direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 455 nm and CIE chromaticity (x, y) = (0.140, 0.120) was obtained. The driving voltage was 6.49 V, and the external quantum efficiency was 4.03%. Further, the time for maintaining the luminance of 80% or more of the initial luminance was 335 hours.

<Example 6>
<Element Using Compound (2-5) for Light Emitting Auxiliary Layer>
An organic EL device was obtained by the method according to Example 1 except that the compound (2-1) as the light emitting auxiliary layer material was changed to the compound (2-5). When a direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 454 nm and CIE chromaticity (x, y) = (0.140, 0.120) was obtained. The driving voltage was 5.08 V and the external quantum efficiency was 4.90%. Further, the time for maintaining the luminance of 80% or more of the initial luminance was 530 hours.

<Example 7>
<Element Using Compound (2-1) for Light Emitting Auxiliary Layer>
An organic EL device was obtained by the method according to Example 1 except that BH-1 as the host material was changed to BH-2. When a direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 456 nm and CIE chromaticity (x, y) = (0.140, 0.130) was obtained. The driving voltage was 5.07 V and the external quantum efficiency was 5.17%. The time for maintaining the brightness of 80% or more of the initial brightness was 570 hours.

<Example 8>
<Element Using Compound (2-1) for Light Emitting Auxiliary Layer>
An organic EL device was obtained by the method according to Example 1 except that BH-1 as the host material was changed to BH-3. When direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 455 nm and CIE chromaticity (x, y) = (0.140, 0.120) was obtained. The driving voltage was 4.86 V and the external quantum efficiency was 5.15%. Further, the time for maintaining the luminance of 80% or more of the initial luminance was 591 hours.

<Example 9>
<Element Using Compound (2-1) for Light Emitting Auxiliary Layer>
An organic EL device was obtained by a method according to Example 1 except that BH-1 as the host material was changed to BH-3 and BD-1 as the dopant material was changed to BD-2. When a direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 466 nm and CIE chromaticity (x, y) = (0.140, 0.200) was obtained. The driving voltage was 4.98 V, and the external quantum efficiency was 5.43%. Further, the time for maintaining the luminance of 80% or more of the initial luminance was 748 hours.

<Example 10>
<Element Using Compound (2-1) for Light Emitting Auxiliary Layer>
An organic EL device was obtained by the method according to Example 1 except that BH-1 as the host material was changed to BH-3 and BD-1 as the dopant material was changed to BD-3. When a direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 459 nm and CIE chromaticity (x, y) = (0.140, 0.150) was obtained. The driving voltage was 5.41 V and the external quantum efficiency was 3.79%. The time for maintaining the luminance of 80% or more of the initial luminance was 408 hours.

<Example 11>
<Element Using Compound (2-1) for Light Emitting Auxiliary Layer>
An organic EL device was obtained by the method according to Example 1 except that BH-1 as the host material was changed to BH-4. When a direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 460 nm and CIE chromaticity (x, y) = (0.140, 0.140) was obtained. The driving voltage was 4.61 V and the external quantum efficiency was 6.20%. The time for maintaining the luminance of 80% or more of the initial luminance was 312 hours.

<Example 12>
<Element Using Compound (2-1) for Light Emitting Auxiliary Layer>
In the same manner as in Example 1, an organic electroluminescent element was obtained. The characteristics at the time of light emission of 1000 cd / m ² were measured using an ITO electrode as an anode and an Al electrode as a cathode, and a wavelength of 454 nm, CIE chromaticity (x, y) = (0.143, 0.120) was measured. ) Blue light emission was obtained. The driving voltage was 4.80 V and the external quantum efficiency was 6.42%. The time for maintaining the luminance of 80% (800 cd / m ² ) or more of the initial luminance was 560 hours.

<Comparative Example 1>
<Element Using Compound (EAL-1) for Light Emitting Auxiliary Layer>
An organic EL device was obtained by a method according to Example 12 except that the compound (2-1) as the light emitting auxiliary layer material was changed to the compound (EAL-1). When a direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 453 nm and CIE chromaticity (x, y) = (0.143, 0.121) was obtained. The driving voltage was 3.72 V and the external quantum efficiency was 6.99%. Further, the time for maintaining the luminance of 80% or more of the initial luminance was 244 hours.

<Example 13>
<Element Using Compound (2-1) for Light Emitting Auxiliary Layer>
An organic EL device was obtained by a method according to Example 12 except that ETL-1 as the electron transport layer material was changed to ETL-5. When a direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 454 nm and CIE chromaticity (x, y) = (0.143, 0.121) was obtained. The driving voltage was 5.95 V and the external quantum efficiency was 5.12%. Further, the time for maintaining the luminance of 80% or more of the initial luminance was 463 hours.

<Example 14>
<Element Using Compound (2-1) for Light Emitting Auxiliary Layer>
An organic EL device was obtained by the method according to Example 12 except that ETL-1 as the electron transport layer material was changed to ETL-3. When a direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 454 nm and CIE chromaticity (x, y) = (0.143, 0.118) was obtained. The driving voltage was 4.38 V and the external quantum efficiency was 7.40%. Further, the time for maintaining the luminance of 80% or more of the initial luminance was 155 hours.

<Example 15>
<Element Using Compound (2-1) for Light Emitting Auxiliary Layer>
An organic EL device was obtained by a method according to Example 12 except that ETL-1 as the electron transport layer material was changed to ETL-6. When a direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 454 nm and CIE chromaticity (x, y) = (0.142, 0.117) was obtained. The driving voltage was 5.62 V and the external quantum efficiency was 5.96%. Further, the time for maintaining the luminance of 80% or more of the initial luminance was 232 hours.

<Example 16>
<Element Using Compound (2-1) for Light Emitting Auxiliary Layer>
An organic EL device was obtained by a method according to Example 12 except that BH-1 as the host material and BD-1 as the dopant material were changed to BH-5 and BD-6, respectively. When direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 457 nm and CIE chromaticity (x, y) = (0.139, 0.099) was obtained. The driving voltage was 4.74 V and the external quantum efficiency was 5.44%. Further, the time for maintaining the luminance of 80% or more of the initial luminance was 219 hours.

<Example 17>
<Element Using Compound (2-1) for Light Emitting Auxiliary Layer>
An organic EL device was obtained by a method according to Example 12 except that BH-1 as the host material and BD-1 as the dopant material were changed to BH-5 and BD-4, respectively. When a direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 460 nm and CIE chromaticity (x, y) = (0.139, 0.143) was obtained. The driving voltage was 4.99 V and the external quantum efficiency was 6.74%. Further, the time for maintaining the luminance of 80% or more of the initial luminance was 500 hours.

<Comparative Example 2>
<Element Using Compound (EAL-1) for Light Emitting Auxiliary Layer>
BH-1 as the host material and BD-1 as the dopant material are replaced with BH-5 and BD-4, respectively, and compound (2-1) as the light emission auxiliary layer material is replaced with compound (EAL-1). An organic EL device was obtained by the method according to Example 12 except that. When a direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 460 nm and CIE chromaticity (x, y) = (0.139, 0.143) was obtained. The driving voltage was 3.78 V, and the external quantum efficiency was 7.54%. In addition, the time for maintaining the luminance of 80% or more of the initial luminance was 301 hours.

<Example 18>
<Element Using Compound (2-1) for Light Emitting Auxiliary Layer>
An organic EL device was obtained by a method according to Example 12 except that BH-1 as the host material and BD-1 as the dopant material were changed to BH-5 and BD-7, respectively. When a direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 454 nm and CIE chromaticity (x, y) = (0.142, 0.101) was obtained. The driving voltage was 4.95 V and the external quantum efficiency was 5.22%. Further, the time for maintaining the luminance of 80% or more of the initial luminance was 258 hours.

<Example 19>
<Element Using Compound (2-1) for Light Emitting Auxiliary Layer>
An organic EL device was obtained by a method according to Example 12 except that BH-1 as the host material and BD-1 as the dopant material were changed to BH-5 and BD-8, respectively. When direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 455 nm and CIE chromaticity (x, y) = (0.144, 0.157) was obtained. The drive voltage was 4.64 V and the external quantum efficiency was 6.34%. Further, the time for maintaining the luminance of 80% or more of the initial luminance was 439 hours.

<Comparative Example 3>
<Element Using Compound (EAL-1) for Light Emitting Auxiliary Layer>
BH-1 as the host material and BD-1 as the dopant material are replaced with BH-5 and BD-8, respectively, and compound (2-1) as the light emitting auxiliary layer material is replaced with compound (EAL-1). An organic EL device was obtained by the method according to Example 12 except that. When a direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 455 nm and CIE chromaticity (x, y) = (0.147, 0.158) was obtained. The drive voltage was 3.59 V and the external quantum efficiency was 6.61%. Further, the time for maintaining the luminance of 80% or more of the initial luminance was 174 hours.

<Example 20>
<Element Using Compound (2-1) for Light Emitting Auxiliary Layer>
An organic EL device was obtained by a method according to Example 12 except that BH-1 as the host material and BD-1 as the dopant material were changed to BH-4 and BD-6, respectively. When a direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 460 nm and CIE chromaticity (x, y) = (0.135, 0.115) was obtained. The driving voltage was 4.47 V and the external quantum efficiency was 7.19%. Further, the time for maintaining the luminance of 80% or more of the initial luminance was 180 hours.

<Comparative example 4>
<Element Using Compound (EAL-1) for Light Emitting Auxiliary Layer>
BH-1 as the host material and BD-1 as the dopant material are replaced with BH-4 and BD-6, respectively, and compound (2-1) as the light emitting auxiliary layer material is replaced with compound (EAL-1). An organic EL device was obtained by the method according to Example 12 except that. When a direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 460 nm and CIE chromaticity (x, y) = (0.135, 0.118) was obtained. The driving voltage was 3.60 V and the external quantum efficiency was 7.39%. Further, the time for maintaining the luminance of 80% or more of the initial luminance was 94 hours.

<Example 21>
<Element Using Compound (2-1) for Light Emitting Auxiliary Layer>
An organic EL device was obtained by a method according to Example 12 except that BH-1 as the host material and BD-1 as the dopant material were changed to BH-4 and BD-5, respectively. When a direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 461 nm and CIE chromaticity (x, y) = (0.135, 0.125) was obtained. The driving voltage was 4.44 V and the external quantum efficiency was 7.07%. In addition, the time for maintaining the luminance of 80% or more of the initial luminance was 350 hours.

<Comparative Example 5>
<Element Using Compound (EAL-1) for Light Emitting Auxiliary Layer>
BH-1 as the host material and BD-1 as the dopant material are replaced with BH-4 and BD-5, respectively, and compound (2-1) as the light emission auxiliary layer material is replaced with compound (EAL-1). An organic EL device was obtained by the method according to Example 12 except that. When direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 462 nm and CIE chromaticity (x, y) = (0.134, 0.128) was obtained. The driving voltage was 3.58 V and the external quantum efficiency was 7.58%. Further, the time for maintaining the luminance of 80% or more of the initial luminance was 109 hours.

<Example 22>
<Element Using Compound (2-62) for Light Emitting Auxiliary Layer>
An organic EL device was obtained by the method according to Example 12 except that the compound (2-1) as the light emitting auxiliary layer material was changed to the compound (2-62). When a direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 457 nm and CIE chromaticity (x, y) = (0.139, 0.126) was obtained. The driving voltage was 5.63 V, and the external quantum efficiency was 6.29%. Further, the time for maintaining the luminance of 80% or more of the initial luminance was 360 hours.

<Example 23>
<Element Using Compound (2-21) for Light Emitting Auxiliary Layer>
An organic EL device was obtained by a method according to Example 12 except that the compound (2-1) as the light emitting auxiliary layer material was changed to the compound (2-21). When a direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 456 nm and CIE chromaticity (x, y) = (0.140, 0.117) was obtained. The driving voltage was 4.77 V and the external quantum efficiency was 6.96%. Further, the time for maintaining the luminance of 80% or more of the initial luminance was 396 hours.

<Example 24>
<Element Using Compound (2-41) for Light Emitting Auxiliary Layer>
An organic EL device was obtained by a method according to Example 12 except that the compound (2-1) as the light emitting auxiliary layer material was changed to the compound (2-41). When a direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 459 nm and CIE chromaticity (x, y) = (0.137, 0.135) was obtained. The driving voltage was 5.38 V and the external quantum efficiency was 5.84%. Further, the time for maintaining the luminance of 80% or more of the initial luminance was 600 hours.

<Example 25>
<Element Using Compound (2-1) for Light Emitting Auxiliary Layer>
In the same manner as in Example 1, an organic electroluminescent element was obtained. The characteristics at the time of light emission of 1000 cd / m ² were measured by applying a direct current voltage using the ITO electrode as the anode and the Al electrode as the cathode. ) Blue light emission was obtained. The driving voltage was 4.90 V and the external quantum efficiency was 5.61%. Further, the time for maintaining the luminance of 80% or more of the initial luminance was 400 hours.

<Example 26>
<Element using Compound (2-3) for Light Emitting Auxiliary Layer>
An organic EL device was obtained by a method according to Example 12 except that the compound (2-1) as the light emitting auxiliary layer material was changed to the compound (2-3). When a direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 456 nm and CIE chromaticity (x, y) = (0.140, 0.120) was obtained. The driving voltage was 5.17 V and the external quantum efficiency was 5.55%. Further, the time for maintaining the luminance of 80% or more of the initial luminance was 407 hours.

<Example 27>
<Element Using Compound (2-5) for Light Emitting Auxiliary Layer>
An organic EL device was obtained by a method according to Example 12 except that the compound (2-1) as the light emitting auxiliary layer material was changed to the compound (2-5). When a direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 456 nm and CIE chromaticity (x, y) = (0.140, 0.120) was obtained. The driving voltage was 5.08 V and the external quantum efficiency was 5.00%. Further, the time for maintaining the luminance of 80% or more of the initial luminance was 530 hours.

<Comparative Example 6>
<Element Using Compound (EAL-1) for Light Emitting Auxiliary Layer>
An organic EL device was obtained by a method according to Example 12 except that the compound (2-1) as the light emitting auxiliary layer material was changed to the compound (EAL-1). When a direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 456 nm and CIE chromaticity (x, y) = (0.143, 0.121) was obtained. The driving voltage was 3.72 V and the external quantum efficiency was 6.99%. Further, the time for maintaining the luminance of 90% (900 cd / m ² ) or more of the initial luminance was 65 hours.

<Example 28>
<Element Using Compound (3-5) for Light Emitting Auxiliary Layer>
An organic EL device was obtained by a method according to Example 12 except that the compound (2-1) as the light emitting auxiliary layer material was changed to the compound (3-5). When a direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 457 nm and CIE chromaticity (x, y) = (0.139, 0.124) was obtained. The driving voltage was 5.32 V and the external quantum efficiency was 6.63%. The time for maintaining the luminance of 90% or more of the initial luminance was 228 hours.

<Example 29>
<Element Using Compound (3-8) for Light Emitting Auxiliary Layer>
An organic EL device was obtained by the method according to Example 12 except that the compound (2-1) as the light emitting auxiliary layer material was changed to the compound (3-8). When a direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 456 nm and CIE chromaticity (x, y) = (0.140, 0.121) was obtained. The driving voltage was 7.50 V and the external quantum efficiency was 5.00%. The time for maintaining the luminance of 90% or more of the initial luminance was 258 hours.

<Example 30>
<Element Using Compound (1-1) for Light Emitting Auxiliary Layer>
An organic EL device was obtained by a method according to Example 12 except that the compound (2-1) as the light emitting auxiliary layer material was changed to the compound (1-1). When a direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 457 nm and CIE chromaticity (x, y) = (0.139, 0.127) was obtained. The driving voltage was 5.89 V and the external quantum efficiency was 6.29%. In addition, the time for maintaining 90% or more of the initial luminance was 331 hours.

<Example 31>
<Element Using Compound (2-87) in Light Emitting Auxiliary Layer>
A method according to Example 12 except that the compound (2-1) as the light emitting auxiliary layer material was changed to the compound (2-87) and ETL-1 as the electron transport layer material was changed to ETL-4. An organic EL device was obtained. When a direct current voltage was applied and the characteristics at 1000 cd / m ² emission were measured, blue emission with a wavelength of 456 nm and CIE chromaticity (x, y) = (0.140, 0.123) was obtained. The driving voltage was 4.64 V and the external quantum efficiency was 6.28%. In addition, the time for maintaining 90% or more of the initial luminance was 131 hours.

  According to a preferred aspect of the present invention, an organic EL element that can efficiently use the TTF phenomenon generated in the light emitting layer and has improved external quantum efficiency, a display device including the same, a lighting device including the same, and the like Can be provided.

DESCRIPTION OF SYMBOLS 100 Organic EL element 101 Substrate 102 Anode 103 Hole injection layer 104 Hole transport layer 105 Light emitting layer 106 Electron transport layer 107 Electron injection layer 108 Cathode 110 Light emission auxiliary layer

Claims (18)

A light-emitting auxiliary layer material used for a light-emitting auxiliary layer between a light-emitting layer and an electron transport layer in an organic electroluminescence device, wherein 1 to 3 benzene rings are present in any one of two benzene rings of fluorene Is a material for a light-emitting auxiliary layer containing a ring-fused fluorene compound and / or a fluorene compound condensed with
The ring-fused fluorene compound and the five-membered ring of the fluorene compound may be substituted with an optionally substituted alkyl and / or an optionally substituted aryl, and two substituents are substituted on the five-membered ring. In some cases, these substituents may combine to form a ring,
At least a part of the benzene ring and / or the condensation site of the ring-fused fluorene compound is substituted with an optionally substituted aryl, and further an optionally substituted alkyl and / or an optionally substituted cycloalkyl. May be substituted, and
At least a part of the benzene ring of the fluorene compound is substituted with an optionally substituted phenyl or condensed ring system aryl, and further substituted with an optionally substituted alkyl and / or an optionally substituted cycloalkyl. And when the substituent on the phenyl or fused ring aryl is aryl, the aryl is phenyl or fused ring aryl.
Light emitting auxiliary layer material. The light emitting auxiliary layer material is a light emitting auxiliary layer material containing a benzofluorene compound, a dibenzofluorene compound, an indenotriphenylene compound, an indenopyrene compound and / or a fluorene compound,
The five-membered ring of the benzofluorene compound, dibenzofluorene compound, indenotriphenylene compound, indenopyrene compound and fluorene compound may be substituted with an optionally substituted alkyl and / or an optionally substituted aryl, When two substituents are substituted on the five-membered ring, these substituents may be bonded to form a ring,
At least a part of the benzene ring and / or the condensation site of the benzofluorene compound, dibenzofluorene compound, indenotriphenylene compound and indenopyrene compound is substituted with an optionally substituted aryl, and an optionally substituted alkyl and And / or optionally substituted cycloalkyl, and
At least a part of the benzene ring of the fluorene compound is substituted with an optionally substituted phenyl or condensed ring system aryl, and further substituted with an optionally substituted alkyl and / or an optionally substituted cycloalkyl. And when the substituent on the phenyl or fused ring aryl is aryl, the aryl is phenyl or fused ring aryl.
The light emitting auxiliary layer material according to claim 1. The fluorene compound is represented by the following general formula (1), the benzofluorene compound is represented by the following general formula (2) or the following general formula (3), and the dibenzofluorene compound is represented by the following general formula (4). The light emitting auxiliary layer material according to claim 2, wherein the indenotriphenylene compound is represented by the following general formula (5) or the following general formula (6), and the indenopyrene compound is represented by the following general formula (7). .

(R ¹ and R ² in the above formulas (2) to (7) are each independently hydrogen, optionally substituted alkyl, optionally substituted cycloalkyl, or optionally substituted aryl. And at least one of R ¹ and R ² is an optionally substituted aryl,
R ¹ and R ² in the above formula (1) are each independently hydrogen, optionally substituted alkyl, optionally substituted cycloalkyl, or optionally substituted phenyl or fused ring system. Is aryl, and at least one of R ¹ and R ² is an optionally substituted phenyl or fused ring aryl, and when the substituent on the phenyl or fused ring aryl is an aryl, the aryl Is phenyl or fused ring aryl, and
R ³ and R ⁴ in the above formulas (1) to (7) are each independently an optionally substituted alkyl or an optionally substituted aryl, and R ³ and R ⁴ are bonded to form a ring. May be formed. ) R ¹ and R ² in the above formulas (2) to (7) are each independently hydrogen, optionally substituted alkyl having 1 to 24 carbon atoms, or optionally substituted 3 to 12 carbon atoms. Cycloalkyl or optionally substituted aryl having 6 to 30 carbon atoms, and at least one of R ¹ and R ² is optionally substituted aryl having 6 to 30 carbon atoms;
R ¹ and R ² in formula (1) are each independently hydrogen, optionally substituted alkyl having 1 to 24 carbon atoms, optionally substituted cycloalkyl having 3 to 12 carbon atoms, or An optionally substituted phenyl having 6 to 30 carbon atoms or a condensed ring aryl, and at least one of R ¹ and R ² may be optionally substituted phenyl having 6 to 30 carbon atoms or a condensed ring. System aryl,
R ³ and R ⁴ in the above formulas (1) to (7) are each independently an optionally substituted alkyl having 1 to 24 carbon atoms or an optionally substituted aryl having 6 to 30 carbon atoms. Each of R ³ and R ⁴ may be combined to form a ring;
The substituents in R ¹ and R ² in the above formulas (2) to (7) are each independently alkyl having 1 to 24 carbon atoms, cycloalkyl having 3 to 12 carbon atoms, or aryl having 6 to 30 carbon atoms. is there,
The substituents in R ¹ and R ² of the above formula (1) are each independently alkyl having 1 to 24 carbon atoms, cycloalkyl having 3 to 12 carbon atoms, phenyl having 6 to 30 carbon atoms, or fused ring aryl. And
The substituents in R ³ and R ⁴ in the above formulas (1) to (7) are each independently alkyl having 1 to 24 carbon atoms, cycloalkyl having 3 to 12 carbon atoms, or aryl having 6 to 30 carbon atoms. is there,
The light emitting auxiliary layer material according to claim 3. R ¹ and R ² in the above formulas (2) to (7) are optionally substituted aryl having 6 to 24 carbon atoms,
R ¹ and R ² in the above formula (1) are optionally substituted phenyl having 6 to 24 carbon atoms or condensed ring aryl,
R ³ and R ⁴ in the above formulas (1) to (7) are each independently an optionally substituted alkyl having 1 to 12 carbon atoms or an optionally substituted aryl having 6 to 16 carbon atoms. Yes, when R ³ and R ⁴ are aryl, the aryls may be bonded to form a ring,
The substituents in R ¹ and R ² in the above formulas (2) to (7) are each independently alkyl having 1 to 12 carbons, cycloalkyl having 3 to 6 carbons or aryl having 6 to 20 carbons. Yes,
The substituents in R ¹ and R ² of the above formula (1) are each independently alkyl having 1 to 12 carbons, cycloalkyl having 3 to 6 carbons, phenyl having 6 to 20 carbons, or a condensed ring aryl. And
The substituents in R ³ and R ⁴ in the above formulas (1) to (7) are each independently alkyl having 1 to 12 carbons, cycloalkyl having 3 to 6 carbons or aryl having 6 to 20 carbons. is there,
The light emitting auxiliary layer material according to claim 3. A benzofluorene compound represented by the general formula (2) or the general formula (3),
R ¹ and R ² are optionally substituted aryl having 6 to 20 carbon atoms,
R ³ and R ⁴ are each independently an optionally substituted alkyl having 1 to 6 carbon atoms or an optionally substituted aryl having 6 to 12 carbon atoms, wherein R ³ and R ⁴ are aryl The aryls may be joined together to form a ring, and
The substituents in R ¹ , R ² , R ³ and R ⁴ are each independently methyl, ethyl, propyl, t-butyl, cyclobutyl, cyclopentyl, cyclohexyl, phenyl, biphenylyl or naphthyl.
The light emitting auxiliary layer material according to claim 3. A benzofluorene compound represented by the general formula (2) or the general formula (3),
R ¹ and R ² are each independently phenyl, biphenylyl, terphenylyl, quaterphenylyl, naphthyl or phenanthryl; and
R ³ and R ⁴ are each independently methyl, ethyl, propyl, t-butyl, phenyl or biphenylyl, phenyl or biphenylyl may be bonded to each other to form a ring,
The light emitting auxiliary layer material according to claim 3. The light emission according to claim 3, which is represented by any one of the following formula (2-1), formula (2-2), formula (2-3), formula (2-4), and formula (2-5). Auxiliary material.

The following formula (1-1), formula (1-71), formula (2-21), formula (2-41), formula (2-61), formula (2-62), formula (2-85), It is represented by any one of formula (2-87), formula (3-5), formula (3-6), formula (3-8), formula (5-7) and formula (6-9), Item 4. The light emitting auxiliary layer material according to Item 3.

A pair of electrodes composed of an anode and a cathode; a light emitting layer disposed between the pair of electrodes; an electron transport layer disposed between the cathode and the light emitting layer; the light emitting layer and the electron transport layer; An organic electroluminescence device having a light emission auxiliary layer disposed between
The organic electroluminescence device, wherein the light emission auxiliary layer is formed of the material for light emission auxiliary layer according to any one of claims 1 to 9. The light emitting layer is composed of a host material and a fluorescent light emitting dopant material having an emission wavelength having a peak at 400 to 500 nm,
The triplet energy E ^T _{h of the} host material is smaller than the triplet energy E ^T _{a of the} light emitting auxiliary layer material,
The organic electroluminescent element according to claim 10. The light emitting layer is composed of a host material and a fluorescent light emitting dopant material having an emission wavelength having a peak at 400 to 500 nm,
The triplet energy E ^T _{d of the} dopant material is greater than the triplet energy E ^T _{h of the} host material,
The organic electroluminescent element according to claim 10 or 11. The light emitting layer is composed of a host material and a fluorescent light emitting dopant material having an emission wavelength having a peak at 400 to 500 nm,
The host material contains at least one selected from the group consisting of anthracene derivatives and pyrene derivatives,
The dopant material contains at least one selected from the group consisting of an amine-containing benzofluorene derivative, an amine-containing pyrene derivative, an amine-free pyrene derivative, an amine-containing chrysene derivative, and an amine-containing styryl derivative.
The organic electroluminescent element according to claim 10.   The organic electroluminescent element according to claim 10, wherein the electron transport layer material contains a heterocyclic ring-containing compound.   The organic electroluminescent device according to claim 14, wherein the heterocyclic ring-containing compound is at least one selected from the group consisting of pyridine derivatives, thiazole derivatives, benzothiazole derivatives, benzimidazole derivatives, phenanthroline derivatives, and phosphine oxide derivatives. . The relationship between the affinity A _a of the light emission auxiliary layer material and the affinity A _e of the electron transport layer material forming the electron transport layer is A _a > A _e −0.8 eV,
The organic electroluminescent element according to claim 10.   A display device comprising the organic electroluminescent element according to claim 10.   The illuminating device provided with the organic electroluminescent element in any one of Claims 10 thru | or 16.

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