JP2017135127A - Organic electroluminescent element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an organic EL element high in luminous efficiency even if having only one hole transport layer and long in service life.SOLUTION: An organic electroluminescent element includes: an anode and a cathode facing to each other; a luminous layer provided between the anode and the cathode; and a hole transportation zone formed between the anode and the luminous layer. The hole transportation zone includes only one hole transport layer in contact with the luminous layer and one hole injection layer in contact with the anode. The hole transport layer contains a compound represented by the following formula (1), and the hole injection layer contains a compound comprising 2-6 aromatic six-membered rings and a specific bonding part.SELECTED DRAWING: None

Description

  The present invention relates to an organic electroluminescence element and a display device or a light emitting device using the same.

  An organic electroluminescence (EL) element is a self-luminous element that utilizes the principle that a fluorescent substance emits light by recombination energy of holes injected from an anode and electrons injected from a cathode by applying an electric field. .

  The organic EL element has a laminated structure including an organic layer such as a hole injection layer, a hole transport layer, an electron injection layer, and an electron transport layer in addition to a light emitting layer between an anode and a cathode. In such an element, in order to increase the recombination efficiency of injected holes and electrons, the material used for each layer and the element structure are devised.

  For example, electron-withdrawing group-containing compounds are known as hole injection materials (for example, Patent Documents 1 to 4). Further, as a hole transport material, trialamine compounds are known (for example, Patent Documents 5 and 6).

International Publication 2009/011327 Pamphlet International Publication 2009/069717 Pamphlet International Publication 2010/064655 Pamphlet JP2010-1000062 International Publication 2014/034795 Pamphlet International Publication 2014/015938 Pamphlet

Providing two hole transport layers reduces the production efficiency and increases the cost.
An object of the present invention is to provide an organic EL device having a high luminous efficiency and a long lifetime even if there is only one hole transport layer.

（式（１）中、Ａｒ^１とＡｒ^２は、それぞれ、置換もしくは無置換のアリール基、又は置換もしくは無置換のヘテロアリール基である。Ｌは、単結合、置換もしくは無置換のアリーレン基、又は置換もしくは無置換のヘテロアリーレン基である。Ｒ^６１〜Ｒ^６３は、それぞれ、置換基である。ｋは０〜５の整数である。ｍは０〜４の整数である。ｎは０〜３の整数である。）

（式（２ｂ）中、Ｘ^２０は、下記式（２ｂ−１）〜（２ｂ−１２）のいずれかで表される。）

（式（２ｂ−１）〜（２ｂ−１２）中、Ｒ^２０は、それぞれ、水素原子、置換もしくは無置換のフルオロアルキル基、置換もしくは無置換のアルキル基、置換もしくは無置換のアリール基又は置換もしくは無置換の複素環基である。） The inventors of the present invention have made it possible to obtain device performance from a large number of hole injection materials and hole transport materials by combining a specific hole injection material and a specific hole transport material, even if there is only one hole transport layer. As a result, it was found that mass productivity can be improved without lowering the temperature, and the present invention has been completed.
According to one aspect of the present invention, the following organic EL device is provided.
Opposing anode and cathode;
A light emitting layer provided between the anode and the cathode, and a hole transport zone formed between the anode and the light emitting layer,
The hole transport zone consists of only one hole transport layer in contact with the light emitting layer and one hole injection layer in contact with the anode,
The hole transport layer includes a compound represented by the following formula (1),
The hole injection layer includes 2 to 6 aromatic six-membered rings and a connecting portion that includes the structure represented by the following formula (2a) or (2b) and connects the aromatic six-membered rings. Each of the aromatic six-membered rings is a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aryl group, substituted or unsubstituted Substituted heterocyclic group, halogen atom, substituted or unsubstituted fluoroalkyl group, substituted or unsubstituted alkoxy group, substituted or unsubstituted fluoroalkoxy group, substituted or unsubstituted aryloxy group, substituted or unsubstituted aralkyloxy The organic electroluminescent element containing the compound which may be substituted by group, a substituted or unsubstituted amino group, or a cyano group.

(In the formula (1), Ar ¹ and Ar ² are each a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group. L is a single bond, a substituted or unsubstituted arylene group, Or a substituted or unsubstituted heteroarylene group, wherein R ^{61 to} R ⁶³ are each a substituent, k is an integer of 0 to 5, m is an integer of 0 to 4, and n is 0 to 0. It is an integer of 3.)

(Formula (2b) ^{in, X 20} is represented by any one of the following formulas (2b-1) ~ (2b -12).)

(In the formulas (2b-1) to (2b-12), R ²⁰ is a hydrogen atom, a substituted or unsubstituted fluoroalkyl group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted group, respectively. Or an unsubstituted heterocyclic group.)

  According to another aspect of the present invention, there is provided a display device or a light emitting device comprising the above organic electroluminescence element.

  ADVANTAGE OF THE INVENTION According to this invention, even if there is only one hole transport layer, the organic EL element with a high luminous efficiency and a long lifetime can be provided.

It is a schematic sectional drawing of the organic EL element concerning one Embodiment of this invention.

FIG. 1 is a schematic cross-sectional view of an organic EL element according to an embodiment of the present invention.
As shown in FIG. 1, the organic EL element 1 of the present invention includes an anode 10 and a cathode 20 facing each other, a light emitting layer 30 provided between the anode 10 and the cathode 20, and a gap between the anode 10 and the light emitting layer 30. And a hole transport zone 40 to be formed. The hole transport zone 40 includes only one hole transport layer 43 in contact with the light emitting layer 30 and one hole injection layer 41 in contact with the anode 10, and does not include other layers. It is preferable to form an electron transport zone 50 between the cathode 20 and the light emitting layer 30. In the present invention, the configuration of the electron transport zone 50 is not limited, and specifically, the type and number of layers are not limited, but it is usually composed of an electron injection layer and an electron transport layer.

  A single layer (one layer) is a single layer even if a part of the layer has changed over time (transfer, storage, use process, etc.). That is, it is a layer formed of the same material (except for inevitable impurities) at the time of manufacture. Alternatively, the affinities in the layer and the ionization potential are the same layer.

  Although the film thickness of the positive hole transport layer 43 and the positive hole injection layer 41 can be set suitably, they are each normally 10 nm-200 nm.

  The organic EL device of the present invention includes a step of forming an anode, a step of forming a hole injection layer, a step of forming a hole transport layer, a step of forming a light emitting layer, and a step of forming a cathode. Between the step of forming the anode and the step of forming the hole injection layer, the step of forming the other layer is not included, the step of forming the hole transport layer, and the step of forming the light emitting layer In the meantime, it can be manufactured by a method that does not include a step of forming another layer. The order of the steps is not limited. The anode may be sequentially formed from the anode to the cathode, or vice versa. In addition, a plurality of stacked bodies formed of some layers may be formed and then bonded.

  In the present invention, by using a predetermined combination of compounds for the hole injection layer 41 and the hole transport layer 43 constituting the hole transport zone 40, specifically, hole injection having a higher acceptor property than conventional ones. By using a monoamine hole transport compound having a wide gap with the compound as a single layer, mass productivity can be improved without deteriorating device performance without providing two hole transport layers.

Hereinafter, compounds used for the hole injection layer 41 and the hole transport layer 43 will be described.
In this specification, the hydrogen atom includes isotopes having different numbers of neutrons, that is, light hydrogen (protium), deuterium (deuterium), and tritium (tritium).

  In this specification, the number of ring-forming carbon atoms constitutes the ring itself of a compound having a structure in which atoms are bonded cyclically (for example, a monocyclic compound, a condensed ring compound, a bridged compound, a carbocyclic compound, or a heterocyclic compound). Represents the number of carbon atoms in the atom. When the ring is substituted with a substituent, the carbon contained in the substituent is not included in the number of ring-forming carbons. The “ring-forming carbon number” described below is the same unless otherwise specified. For example, the benzene ring has 6 ring carbon atoms, the naphthalene ring has 10 ring carbon atoms, the pyridinyl group has 5 ring carbon atoms, and the furanyl group has 4 ring carbon atoms. Further, when an alkyl group is substituted as a substituent on the benzene ring or naphthalene ring, the carbon number of the alkyl group is not included in the number of ring-forming carbons. In addition, for example, when a fluorene ring is bonded to the fluorene ring as a substituent (including a spirofluorene ring), the carbon number of the fluorene ring as a substituent is not included in the number of ring-forming carbons.

  In this specification, the number of ring-forming atoms means a compound (for example, a monocyclic compound, a condensed ring compound, a bridging compound, a carbocyclic compound, a heterocycle) having a structure in which atoms are bonded in a cyclic manner (for example, a monocyclic ring, a condensed ring, or a ring assembly) Of the ring compound) represents the number of atoms constituting the ring itself. An atom that does not constitute a ring (for example, a hydrogen atom that terminates a bond of an atom that constitutes a ring) or an atom contained in a substituent when the ring is substituted by a substituent is not included in the number of ring-forming atoms. The “number of ring-forming atoms” described below is the same unless otherwise specified. For example, the pyridine ring has 6 ring atoms, the quinazoline ring has 10 ring atoms, and the furan ring has 5 ring atoms. A hydrogen atom bonded to a carbon atom of a pyridine ring or a quinazoline ring or an atom constituting a substituent is not included in the number of ring-forming atoms. Further, when, for example, a fluorene ring is bonded to the fluorene ring as a substituent (including a spirofluorene ring), the number of atoms of the fluorene ring as a substituent is not included in the number of ring-forming atoms.

  In the present specification, “atom number XX to YY” in the expression “a ZZ group having a substituted or unsubstituted atom number XX to YY” represents the number of atoms when the ZZ group is unsubstituted, In this case, the number of substituent atoms is not included. Here, “YY” is larger than “XX”, and “XX” and “YY” each mean an integer of 1 or more.

  In the present specification, “unsubstituted” in the case of “substituted or unsubstituted” means that a hydrogen atom is bonded without being substituted with the substituent.

This invention contains the compound represented by following formula (1) in a positive hole transport layer. Preferably it consists essentially of this compound.

In formula (1), Ar ¹ and Ar ² are each a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group. L is a single bond, a substituted or unsubstituted arylene group, or a substituted or unsubstituted heteroarylene group. R ^{61 to} R ⁶³ are each a substituent. k is an integer of 0-5. m is an integer of 0-4. n is an integer of 0-3.

式（１１）〜（１９）中、Ｒ^６１，ｋ，ｍ，ｎは、式（１）のＲ^６１，ｋ，ｍ，ｎと同じである。
Ｘ’は、酸素原子又は硫黄原子である。
Ｌ^１は式（１）のＬと同じであり、
Ｒ^７１は、水素原子、又はＲ^６１と同じ基である。
式（１１）において、Ｒ^６１はカルバゾール骨格の任意の位置に結合してよく、Ｌ^１はカルバゾール骨格の任意の位置に結合してよい。
式（１３）において、Ｒ^６１はジベンゾフラン骨格又はジベンゾチオフェン骨格の任意の位置に結合してよく、Ｌ^１はジベンゾフラン骨格又はジベンゾチオフェン骨格の任意の位置に結合してよい。
式（１２），（１４）〜（１９）において、Ｒ^６１はベンゼン環の任意の位置に結合してよく、Ｌ^１はベンゼン環の任意の位置に結合してよい。 Ar ¹ and Ar ² are each preferably selected from the following formulas (11) to (19).

Wherein ^{(11) ~ (19),} R 61, k, m, n are the same ^R 61, k of formula (1), m, and n.
X ′ is an oxygen atom or a sulfur atom.
L ¹ is the same as L in formula (1),
R ⁷¹ is a hydrogen atom or the same group as R ⁶¹ .
In the formula (11), R ⁶¹ may be bonded to any position of the carbazole skeleton, and L ¹ may be bonded to any position of the carbazole skeleton.
In the formula (13), R ⁶¹ may be bonded to any position of the dibenzofuran skeleton or the dibenzothiophene skeleton, and L ¹ may be bonded to any position of the dibenzofuran skeleton or the dibenzothiophene skeleton.
In the formulas (12) and (14) to (19), R ⁶¹ may be bonded to any position of the benzene ring, and L ¹ may be bonded to any position of the benzene ring.

式中、Ｒ^６１，ｍ，ｎは、式（１）のＲ^６１，ｍ，ｎと同じである。 R ⁷³ and R ⁷⁵ are the same as R ⁶² and R ^{63 in} the formula (1). However, R ⁷³ and R ⁷⁵ may form a ring. For example, the following spirofluorene can be formed. An alkyl group is preferred.

^{Wherein, R} 61, m, n are the same as ^R 61, m, n of formula (1).

In one embodiment of the present invention, the groups of the formula (16) and the formula (17) can be bonded to the nitrogen atom at the para position, the ortho position, or the meta position as follows.

L is preferably or a group represented by the following formula (20).

In Formula (20), when n is 0, L is a single bond. When n is plural, plural R ⁶¹ , m may be the same or different, and R ⁶¹ may be bonded to each other to form a ring. n is preferably 0 to 2, more preferably 0.
In addition, n benzene rings are preferably bonded to each other at the para position.

L ¹ is preferably a single bond or a phenylene group.

L ¹ is preferably bonded to the 3-position of the carbazole skeleton as shown in the following formula.

L ¹ is preferably bonded to the 2-position or 4-position of the dibenzofuran skeleton and the dibenzothiophene skeleton as shown in the following formula.

L ¹ is preferably bonded to the 2-position of the fluorene skeleton as shown in the following formula.

When the compound of Formula (1) has a plurality of L ¹ , the plurality of L ¹ may be the same or different.

R ⁶¹ represents a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a halogen atom, a substituted or unsubstituted fluoroalkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted fluoroalkoxy group, or Represents a cyano group. When the aromatic amine derivative of the formula (1) has a plurality of R ⁶¹ , the plurality of R ⁶¹ may be the same or different.

R ⁶¹ is preferably a halogen atom (particularly a fluorine atom), an alkyl group (particularly a methyl group or a t-butyl group), or an aryl group (phenyl group). R ^{61 in the} formulas (15) to (18) is preferably a group containing fluorine.

R ⁶² and R ⁶³ may be the same or different and each independently represents a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a halogen atom, substituted or unsubstituted A fluoroalkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted fluoroalkoxy group, a substituted or unsubstituted aryloxy group, or a cyano group. When the aromatic amine derivative of the formula (1) has a plurality of R ⁶² , the plurality of R ⁶² may be the same or different. When the aromatic amine derivative has a plurality of R ⁶³ , the plurality of R ⁶³ are the same or different. May be.

In a preferred embodiment of the present ^invention, as the ^{R 62} and ^{R 63,} an alkyl group (especially methyl, t- butyl group), an aryl group (especially phenyl group), or a cyano group is preferable, ^{also, R 62} and ^{R 63} is Each is preferably bonded to the para position of the phenyl group.

k is 0, 1, 2, 3, 4, or 5. Preferably it is an integer of 0 to 3, more preferably 1.
m is 0, 1, 2, 3, or 4. Preferably it is an integer of 0 to 3, more preferably 1.
n is an integer of 0, 1, 2, 3, preferably an integer of 0 to 2, more preferably 1.

Specific examples of the compound of formula (1) are shown below, but are not limited thereto.

The present invention includes 2, 3, 4, 5, 6 (preferably 3) aromatic six-membered rings and a structure represented by the following formula (2a) or (2b) in the hole injection layer. The compound which consists of a connection part which connects the said aromatic 6-membered ring is included. Preferably it consists essentially of this compound. The aromatic six-membered ring contained in this compound includes a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted group, respectively. Substituted heterocyclic group, halogen atom, substituted or unsubstituted fluoroalkyl group, substituted or unsubstituted alkoxy group, substituted or unsubstituted fluoroalkoxy group, substituted or unsubstituted aryloxy group, substituted or unsubstituted aralkyloxy It may be substituted with a group, a substituted or unsubstituted amino group, or a cyano group.
The structure represented by the formula (2a) or (2b) is not included in the substituted or unsubstituted aromatic six-membered ring to be linked.

（式（２ｂ）中、Ｘ^２０は、下記式（２ｂ−１）〜（２ｂ−１２）のいずれかで表される。）

（式（２ｂ−１）〜（２ｂ−１２）中、Ｒ^２０は、それぞれ、水素原子、置換もしくは無置換のフルオロアルキル基、置換もしくは無置換のアルキル基、置換もしくは無置換のアリール基又は置換もしくは無置換の複素環基である。）

(Formula (2b) ^{in, X 20} is represented by any one of the following formulas (2b-1) ~ (2b -12).)

(In the formulas (2b-1) to (2b-12), R ²⁰ is a hydrogen atom, a substituted or unsubstituted fluoroalkyl group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted group, respectively. Or an unsubstituted heterocyclic group.)

  Each of the 2 to 6 aromatic 6-membered rings is preferably a hydrocarbon ring, more preferably an aromatic hydrocarbon ring such as a benzene ring. Also preferred are nitrogen-containing rings, more preferred are aromatic nitrogen-containing rings such as pyridine and pyrazine.

式（２）中、Ｘは、それぞれ、下記式で表される基である。
Ｒ^２００−Ｃ^＊−ＣＮ
（上記式中、Ｃ^＊は二重結合で式（２）のシクロプロパンに結合する炭素原子である。
Ｒ^２００は、それぞれ、芳香族６員環、ハロゲン原子、置換もしくは無置換のフルオロアルキル基、置換もしくは無置換のフルオロアルコキシ基及びシアノ基から選択される１以上で置換されている芳香族６員環である。） As the compound used for the hole injection layer, comprising 2 to 6 aromatic 6-membered rings and a linking moiety that includes the structure represented by the formula (2a) and connects the aromatic 6-membered rings, Specifically, a compound represented by the following formula (2) is exemplified.

In formula (2), each X is a group represented by the following formula.
R ²⁰⁰ -C ^* -CN
(In the above formula, C ^* is a carbon atom bonded to the cyclopropane of the formula (2) by a double bond.
R ²⁰⁰ is an aromatic 6-membered ring substituted with one or more selected from an aromatic 6-membered ring, a halogen atom, a substituted or unsubstituted fluoroalkyl group, a substituted or unsubstituted fluoroalkoxy group, and a cyano group, respectively. It is a ring. )

R ^{200 in} formula (2) is preferably perfluoropyridin-4-yl, tetrafluoro-4- (trifluoromethyl) phenyl group, 4-cyanoperfluorophenyl, dichloro-3,5-difluoro-4- (tri Fluoromethyl) phenyl or perfluorophenyl.

  As a specific compound of the formula (2), (2E, 2′E, 2 ″ E) -2,2 ′, 2 ″-(cyclopropane-1,2,3-triylidene) tris (2- ( Perfluorophenyl) -acetonitrile), (2E, 2′E, 2 ″ E) -2,2 ′, 2 ″-(cyclopropane-1,2,3-triylidene) tris (2- (perfluoropyridine-4) -Yl) -acetonitrile), (2E, 2′E, 2 ″ E) -2,2 ′, 2 ″-(cyclopropane-1,2,3-triylidene) tris (2- (4-cyanoperfluoro Phenyl) -acetonitrile), (2E, 2′E, 2 ″ E) -2,2 ′, 2 ″-(cyclopropane-1,2,3-triylidene) tris (2- (2,3,5 , 6-Tetrafluoro-4- (trifluoromethyl) phenyl) -a Nitrile) or (2E, 2′E, 2 ″ E) -2,2 ′, 2 ″-(cyclopropane-1,2,3-triylidene) tris (2- (2,6-dichloro- 3,5-difluoro-4- (trifluoromethyl) phenyl) -acetonitrile) and the like.

Examples of the compound of the formula (2) are shown below.

As a compound comprising 2-6 aromatic 6-membered rings used in the hole injection layer and a linking portion that includes the structure represented by formula (2b) and connects the aromatic 6-membered rings, Specifically, a compound represented by the following formula (3) is exemplified.

In the formula (3), Ar ¹ is a substituted or unsubstituted monocyclic or condensed ring having 6 to 24 ring carbon atoms, or a heterocyclic ring having 6 to 24 ring atoms, preferably 6 to 6 ring forming carbon atoms. 14 monocyclic or condensed rings, or heterocyclic rings having 6 to 14 ring atoms. Examples of the monocyclic ring or condensed ring include a benzene ring, naphthalene ring, fluorene ring, 9,9-dimethylfluorene ring, 9,9-dioctylfluorene ring, and the like. Examples of the heterocyclic ring include a pyrazine ring, a pyridine ring, a quinoxaline ring, a thiophene ring, a benzothiophene ring, a dibenzothiophene ring, a furan ring, a benzofuran ring, a dibenzofuran ring, a phenanthroline ring, and a naphthyridine ring. The ring of Ar ¹ is preferably an aromatic ring.

In formula (3), R ^{1 to} R ⁴ are each a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, or a substituted or unsubstituted aryl group. Substituted or unsubstituted heterocyclic group, halogen atom, substituted or unsubstituted fluoroalkyl group, substituted or unsubstituted alkoxy group, substituted or unsubstituted fluoroalkoxy group, substituted or unsubstituted aryloxy group, substituted or unsubstituted A substituted aralkyloxy group, a substituted or unsubstituted amino group, or a cyano group. R ¹ and R ² and R ³ and R ⁴ may be bonded to each other to form a saturated or unsaturated divalent group constituting a ring.

As described above, R ¹ and R ² and R ³ and R ⁴ may be bonded to each other to form a saturated or unsaturated divalent group constituting a ring. Examples of the ring include a benzene ring, a naphthalene ring, a pyrazine ring, a pyridine ring, and a furan ring.

Furthermore, at least one of R ^{1 to} R ⁴ is a fluorine atom, a fluoroalkyl group, a fluoroalkoxy group, a cyano group, or at least one group selected from fluorine, a fluoroalkyl group, a fluoroalkoxy group, and a cyano group. An aryl group or a heterocyclic group is preferable. By using these as substituents, electron acceptability can be increased, an appropriate sublimation temperature can be obtained, or crystallization can be suppressed.

Ar ¹ and ar ² in the formula (3) are respectively the following formulas (i) or (ii).

In the formula, X ¹ and X ² may be the same as or different from each other, and are the same as X ²⁰ . In particular, (2b-1) to (2b-3) are preferable from the viewpoint of excellent heat resistance or ease of synthesis.

In formula (3), Y ^{1 to} Y ⁴ may be the same as or different from each other, and are —N═, —CH═, or —C (R ⁵ ) =, and R ⁵ is the same as R ^{1 to} R ⁴ described above. It is synonymous. R ^{1 to} R ⁵ adjacent to each other may be bonded to each other to form a saturated or unsaturated divalent group constituting a ring.
Further, at least one of Y ^{1 to} Y ⁴ is preferably a nitrogen atom (the same applies to Y ⁵ to Y ¹⁰ , Y ^{11 to} Y ¹⁴ , Y ^{21 to} Y ²⁶ and Y ^{31 to} Y ³⁸ described later). . Since at least one is a nitrogen atom, electron acceptability can be increased, heat resistance can be increased, or crystallization can be suppressed.

The indenofluorenedione derivative of formula (3) is preferably represented by the following formula (A) or (B). Each sign of Ar ¹ such as in the following formula (A) are as defined for formula (3). Ar ² in the following formula (B) is synonymous with Ar ¹ in formula (3), X ³ and X ⁴ are synonymous with X ¹ and X ² in formula (3), and Y ^{5 to} Y ⁸ are formulas. (3) have the same meanings as ^Y 1 to Y ^{4 in,} R 1 to R ⁴ have the same meanings as ^R 1 to R ⁴ in the formula (3).

More preferably, the compound of the formula (3) is represented by the following formulas (I) to (IX).

In the above formulas, ^{X 1} and ^{X 2} have the same meanings as ^{X 1} and ^{X 2} in the formula (3). X ¹ and X ² are each preferably the above (2b-1) or (2b-2), and more preferably the same. R ¹ to R ⁴ and ^R 8 ^{to R 17} have the same meanings as defined in ^R 1 to R ⁴ in the formula ^(3), at least one of R 1 to R ⁴ and ^R 8 ^{to R 17} is a fluorine atom, a fluoroalkyl group, It is preferably a fluoroalkoxy group, a cyano group, or an aryl group or heterocyclic group having at least one group selected from fluorine, a fluoroalkyl group, a fluoroalkoxy group, and a cyano group. ^{Y 5 ~Y 10, Y 11 ~Y} 14, Y 21 ~Y 26 and ^Y 31 ^{to Y 38} are the same meaning as ^Y 1 to Y ⁴ in formula (3).

Particularly preferred compounds of the formula (3) are shown below. Even when a plurality of isomers are included, the specific isomer is not limited.

In the above ^{formula, R 11 ~R 30, R 31} ~R 52 has the same meaning as ^R 1 to R ⁴ in the formula (3). R ^{31 to} R ⁵² adjacent to each other may be bonded to each other to form a saturated or unsaturated divalent group constituting a ring. In particular, at least one of R ^{31 to} R ⁵² is a fluorine atom, a fluoroalkyl group, a fluoroalkoxy group, a cyano group, or an aryl having at least one group selected from fluorine, a fluoroalkyl group, a fluoroalkoxy group, and a cyano group It is preferably a group or a heterocyclic group.

Specific examples of the compound of formula (3) are shown below, but are not limited thereto.

Preferred examples or specific examples of the above groups are shown below.
The alkyl group, the alkyl part of the fluoroalkyl group, the alkyl part of the alkoxy group, and the alkyl part of the fluoroalkoxy group have, for example, 1 to 20 carbon atoms, preferably 1 to 8 carbon atoms, and more preferably 1 to 4 carbon atoms.
A cycloalkyl group is C3-C20, for example, Preferably it is 5-10, More preferably, it is 5-6.
The alkenyl group has, for example, 2 to 20 carbon atoms, preferably 2 to 8 carbon atoms, more preferably 2 to 4 carbon atoms.
The aryl group or arylene group has, for example, 6 to 50 ring carbon atoms, preferably 6 to 24, and more preferably 6 to 12.
In the aralkyloxy group, the alkyl moiety has, for example, 1 to 20 carbon atoms, preferably 1 to 8, more preferably 1 to 4, and the aryl moiety has, for example, 6 to 50 ring carbon atoms, preferably 6 to 24 carbon atoms. Preferably it is 6-12.
The heterocyclic group, heteroaryl group or heteroarylene group has, for example, 3 to 50 ring-forming atoms, preferably 3 to 24, more preferably 3 to 12.
The aryloxy group has, for example, 6 to 50 carbon atoms, preferably 6 to 24 carbon atoms, and more preferably 6 to 12 carbon atoms.

  Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, s-butyl group, t-butyl group, pentyl group (including isomers), and hexyl. Groups (including isomers), heptyl groups (including isomers), octyl groups (including isomers), nonyl groups (including isomers), decyl groups (including isomers), undecyl groups (including isomers) And dodecyl group (including isomers) and the like, and include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, s-butyl group, t-butyl group, and Pentyl groups (including isomers) are preferred, methyl groups, ethyl groups, n-propyl groups, isopropyl groups, n-butyl groups, isobutyl groups, s-butyl groups, and t-butyl groups are more preferred, and methyl groups and - butyl group is particularly preferable.

  Examples of (substituted) aryl groups include phenyl, naphthylphenyl, biphenylyl, terphenylyl, biphenylenyl, naphthyl, phenylnaphthyl, acenaphthylenyl, anthryl, benzoanthryl, and aceanthryl groups. Phenanthryl group, benzophenanthryl group, phenalenyl group, fluorenyl group, 9,9-dimethylfluorenyl group, 7-phenyl-9,9-dimethylfluorenyl group, pentacenyl group, picenyl group, pentaphenyl group, Pyrenyl group, chrysenyl group, benzochrysenyl group, s-indacenyl group, as-indacenyl group, fluoranthenyl group, perylenyl group, fluorophenyl group, trifluoromethylphenyl group, (trifluoromethyl) fluorophenyl group, trifluorophenyl group , Bi (Trifluoromethyl) phenyl group, (trifluoromethyl) difluorophenyl group, trifluoromethoxyphenyl group, trifluoromethoxyfluorophenyl group, etc. are mentioned, phenyl group, naphthylphenyl group, biphenylyl group, terphenylyl group, A naphthyl group and a 9,9-dimethylfluorenyl group are preferable, a phenyl group, a biphenylyl group, a naphthyl group, and a 9,9-dimethylfluorenyl group are more preferable, and a phenyl group is particularly preferable. The same applies to the (substituted) arylene group.

  The halogen atom is a fluorine atom, a chlorine atom, a bromine atom or an iodine atom, and a fluorine atom is particularly preferred.

  Examples of the fluoroalkyl group include groups obtained by substituting at least one hydrogen atom, preferably 1 to 7 hydrogen atoms, of the above alkyl group having 1 to 20 carbon atoms with a fluorine atom. Fluoropropyl group, pentafluoroethyl group, 2,2,2-trifluoroethyl group, trifluoromethyl group, perfluorocyclohexyl group, perfluoroadamantyl group, 2,2,3,3,3-pentafluoropropoxy group, 2,2,3,3-tetrafluoropropoxy group, 1,1,1,3,3,3-hexafluoropropan-2-yloxy group are preferred, pentafluoroethyl group, 2,2,2-trifluoroethyl Group, trifluoromethyl group is more preferable, and trifluoromethyl group is particularly preferable.

  As an alkoxy group, a t-butoxy group, a propoxy group, an ethoxy group, and a methoxy group are preferable, an ethoxy group and a methoxy group are more preferable, and a methoxy group is particularly preferable.

  As the fluoroalkoxy group, a heptafluoropropoxy group, a pentafluoroethoxy group, a 2,2,2-trifluoroethoxy group, and a trifluoromethoxy group are preferable, a pentafluoroethoxy group, a 2,2,2-trifluoroethoxy group, A trifluoromethoxy group is more preferable, and a trifluoromethoxy group is particularly preferable.

  The heterocyclic group contains at least 1, preferably 1 to 3 heteroatoms such as nitrogen, sulfur and oxygen atoms. Examples of the heterocyclic group include pyrrolyl, furyl, thienyl, thiophenyl, pyridyl, pyridazinyl, pyrimidinyl, pyrazinyl, triazinyl, imidazolyl, oxazolyl, thiazolyl, pyrazolyl, isoxazolyl , Isothiazolyl group, oxadiazolyl group, thiadiazolyl group, triazolyl group, indolyl group, isoindolyl group, benzofuranyl group, isobenzofuranyl group, benzothiophenyl group, indolizinyl group, quinolidinyl group, quinolyl group, isoquinolyl group, cinnolyl group, phthalazinyl group , Quinazolinyl group, quinoxalinyl group, benzimidazolyl group, benzoxazolyl group, benzthiazolyl group, indazolyl group, benzisoxazolyl group, benzisothiazolyl group, dibenzofurani Group, dibenzothiophenyl group, phenanthridinyl group, acridinyl group, phenanthrolinyl group, phenazinyl group, phenothiazinyl group, phenoxazinyl group, and xanthenyl group, and the like. Furyl group, thienyl group, pyridyl group, pyridazinyl Group, pyrimidinyl group, pyrazinyl group, triazinyl group, benzofuranyl group, benzothiophenyl group, dibenzofuranyl group, dibenzothiophenyl group are preferable, benzofuranyl group, benzothiophenyl group, dibenzofuranyl group, dibenzothiophenyl group are more preferable. The same applies to the (substituted) heteroarylene group.

  As the aryloxy group, a terphenyloxy group, a biphenyloxy group and a phenoxy group are preferable, a biphenyloxy group and a phenoxy group are more preferable, and a phenoxy group is particularly preferable.

Examples of the cycloalkyl group include a cyclopentyl group and a cyclohexyl group.
Alkenyl groups include vinyl groups, propenyl groups (including double bond positional isomers), butenyl groups (including double bond positional isomers), pentenyl groups (including double bond positional isomers), etc. can give.
Examples of (substituted) aralkyloxy groups include benzyloxy group, pentafluorobenzyloxy group, 4-trifluoromethylbenzyloxy group and the like.
Examples of (substituted) amino groups include amino groups, mono- or dimethylamino groups, mono- or diethylamino groups, mono- or diphenylamino groups, and the like.

In the above, the optional substituent when referred to as “substituted or unsubstituted” is an alkyl group having 1 to 50 carbon atoms (preferably 1 to 10, more preferably 1 to 5); 1 to 50 carbon atoms (preferably 1 -10, more preferably 1-5) fluoroalkyl group; ring carbon number 3-50 (preferably 3-6, more preferably 5 or 6) cycloalkyl group; ring carbon number 6-50 (preferably 6). To 24, more preferably 6 to 12) aryl group; 1 to 50 carbon atoms (preferably 1 to 10) having an aryl group having 6 to 50 ring carbon atoms (preferably 6 to 24, more preferably 6 to 12) ring carbon atoms. , More preferably 1-5) aralkyl group; amino group; mono- or dialkylamino group having an alkyl group having 1 to 50 carbon atoms (preferably 1 to 10, more preferably 1 to 5 carbon atoms); ~ 50 (good Or a mono- or diarylamino group having an aryl group of 6 to 24, more preferably 6 to 12); an alkoxy having an alkyl group having 1 to 50 carbon atoms (preferably 1 to 10, more preferably 1 to 5 carbon atoms). Group: a fluoroalkoxy group having an alkyl group having 1 to 50 carbon atoms (preferably 1 to 10, more preferably 1 to 5); 6 to 50 ring carbon atoms (preferably 6 to 24, more preferably 6 to 12) An aryloxy group having an aryl group of: an alkyl group having 1 to 50 carbon atoms (preferably 1 to 10, more preferably 1 to 5) and a ring carbon number 6 to 50 (preferably 6 to 24, more preferably 6 to 6). 12) a mono-, di- or tri-substituted silyl group having a group selected from aryl groups; 5 to 50 ring atoms (preferably 5 to 24, more preferably 5 to 12) and heteroatoms Heteroaryl group containing 1 to 5 (preferably 1 to 3, more preferably 1 to 2) nitrogen atom, oxygen atom, sulfur atom); halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom) Selected from the group consisting of a cyano group and a nitro group;
These substituents may be further substituted with the above substituents. A plurality of these substituents may be bonded to each other to form a ring.

  Hereinafter, layers other than the hole transport zone constituting the organic EL element will be described. In addition, the layer and material which comprise an organic EL element are not limited to the following.

(substrate)
The substrate is used as a support for the light emitting element. As the substrate, for example, glass, quartz, plastic, or the like can be used. Further, a flexible substrate may be used. The flexible substrate is a substrate that can be bent (flexible), and examples thereof include a plastic substrate made of polycarbonate or polyvinyl chloride.

(anode)
For the anode formed on the substrate, it is preferable to use a metal, an alloy, an electrically conductive compound, a mixture thereof, or the like having a high work function (specifically, 4.0 eV or more). Specifically, for example, indium oxide-tin oxide (ITO: Indium Tin Oxide), indium oxide-tin oxide containing silicon or silicon oxide, indium oxide-zinc oxide, tungsten oxide, and indium oxide containing zinc oxide. And graphene. In addition, gold (Au), platinum (Pt), a nitride of a metal material (for example, titanium nitride), or the like can be given.

(Guest material for light emitting layer)
The light-emitting layer is a layer including a substance having high light-emitting properties, and various materials can be used. For example, as the substance having high light-emitting property, a fluorescent compound that emits fluorescence or a phosphorescent compound that emits phosphorescence can be used. A fluorescent compound is a compound that can emit light from a singlet excited state, and a phosphorescent compound is a compound that can emit light from a triplet excited state.

  As a blue fluorescent material that can be used for the light emitting layer, pyrene derivatives, styrylamine derivatives, chrysene derivatives, fluoranthene derivatives, fluorene derivatives, diamine derivatives, triarylamine derivatives, and the like can be used. An aromatic amine derivative or the like can be used as a green fluorescent material that can be used for the light emitting layer. Tetracene derivatives, diamine derivatives, and the like can be used as red fluorescent materials that can be used for the light emitting layer.

  As a blue phosphorescent material that can be used for the light emitting layer, a metal complex such as an iridium complex, an osmium complex, or a platinum complex is used. An iridium complex or the like is used as a green phosphorescent material that can be used in the light emitting layer. As a red phosphorescent material that can be used for the light emitting layer, a metal complex such as an iridium complex, a platinum complex, a terbium complex, or a europium complex is used.

(Host material for light emitting layer)
The light-emitting layer may have a structure in which the above-described highly light-emitting substance (guest material) is dispersed in another substance (host material). Various materials can be used as a material for dispersing a highly luminescent substance. The lowest unoccupied orbital level (LUMO level) is higher than that of a highly luminescent substance, and the highest occupied orbital level ( It is preferable to use a substance having a low HOMO level.

  Substances (host materials) for dispersing highly luminescent substances include 1) metal complexes such as aluminum complexes, beryllium complexes, or zinc complexes, 2) oxadiazole derivatives, benzimidazole derivatives, phenanthroline derivatives, etc. Heterocyclic compounds, 3) condensed aromatic compounds such as carbazole derivatives, anthracene derivatives, phenanthrene derivatives, pyrene derivatives, or chrysene derivatives, 3) aromatic amine compounds such as triarylamine derivatives, or condensed polycyclic aromatic amine derivatives used.

(Electron transport layer)
The electron transport layer is a layer containing a substance having a high electron transport property. For the electron transport layer, 1) metal complexes such as aluminum complexes, beryllium complexes, and zinc complexes, 2) heteroaromatic compounds such as imidazole derivatives, benzimidazole derivatives, azine derivatives, carbazole derivatives, and phenanthroline derivatives, and 3) polymer compounds Can be used.

(Electron injection layer)
The electron injection layer is a layer containing a substance having a high electron injection property. The electron injection layer includes an alkali metal such as lithium (Li), lithium fluoride (LiF), cesium fluoride (CsF), calcium fluoride (CaF2), lithium oxide (LiOx), an alkaline earth metal, Alternatively, those compounds can be used.

(cathode)
For the cathode, it is preferable to use a metal, an alloy, an electrically conductive compound, a mixture thereof, or the like having a small work function (specifically, 3.8 eV or less). Specific examples of such cathode materials include elements belonging to Group 1 or Group 2 of the periodic table of elements, that is, alkali metals such as lithium (Li) and cesium (Cs), and alkaline earth such as magnesium (Mg). And other rare earth metals such as alloys, alloys containing them (for example, MgAg, AlLi), and alloys containing these.

  The organic EL element of the present invention is used in various display devices or light emitting devices. For example, it can be suitably used for light sources such as flat light emitters and display backlights, display units such as mobile phones, PDAs, car navigation systems, car instrument panels, and lighting.

-Used compounds The compounds used in Examples and Comparative Examples are as follows.
[Hole injection compound]

[Hole transport compound]

[Host compound]

[Dopant compound]

[Electron transport compound or electron injection compound]

Example 1
A hole injection compound HI, a hole transport compound HT-1, a host material BH1 and a dopant material BD1 ((the dopant material is 5% by weight), an electron on an ITO substrate on which ITO (anode) having a film thickness of 130 nm is formed. The transport compound ET-1 and Liq (Liq is 50% by weight), the electron injection compound Liq, and the cathode material aluminum were sequentially deposited and laminated to obtain an element having the following structure. ).
ITO (130) / HI / HT-1 (90) / BH1: BD1 (20) (5%) / ET-1: Liq (30: 50%) (30) (50%) / Liq (1) / Al (80)

The following evaluation was performed about the obtained element. The results are shown in Table 1.
(1) Initial performance (voltage, current density, external quantum efficiency)
A voltage was applied to the device so that the current density was 1 mA / cm ^2, and the voltage value at that time was measured. Further, the EL emission spectrum at that time was measured using a spectral radiance meter (CS-1000: manufactured by Comica Minolta). The external quantum efficiency (EQE) (%) was calculated from the obtained spectral radiance spectrum.

(2) LT90
The lifetime LT90 was measured by applying a voltage to the device so that the current density was 50 mA / cm ² and measuring the time (unit: hrs) until the luminance reached 90% with respect to the initial luminance.

Examples 2 to 5, Comparative Examples 1 and 2
A device was obtained and evaluated in the same manner as in Example 1 except that the hole transport compound was changed to the compounds shown in Table 1 in Example 1. The results are shown in Table 1.

Comparative Examples 3-8
In Example 1, the hole transport layer that was one layer was changed to two layers (hole transport layer 1 (film thickness 75 nm) and hole transport layer 2 (film thickness 15 nm)) composed of the compounds shown in Table 1. Otherwise, an element was obtained and evaluated in the same manner as in Example 1. The results are shown in Table 1.
In the table, the hole transport layer 1 is on the anode side.

Example 6
A hole injection compound HI, a hole transport compound HT-5, a host material BH2 and a dopant material BD2 (a dopant material is 4% by weight), first, on an ITO substrate on which a 130 nm-thick ITO (anode) film is formed. The electron transport compound ET-2, the second electron transport compound ET-3, the electron injection compound LiF, and the cathode material aluminum were sequentially deposited and laminated to obtain an element having the following configuration. The parentheses indicate the film thickness (unit: nm).
Evaluation was performed in the same manner as in Example 1. The results are shown in Table 2.
ITO (130) / HI (10) / HT-5 (90) / BH2: BD2 (25) (4%) / ET-2 (25) / ET-3 (10) / LiF (1) / Al (80 )

Comparative Example 9
In Example 6, a device was obtained and evaluated in the same manner as in Example 6 except that the hole injection compound was changed to the compounds shown in Table 2. The results are shown in Table 2.

Comparative Example 10
In Example 6, the single hole transport layer was changed to two layers (hole transport layer 1 (thickness 80 nm) and hole transport layer 2 (thickness 10 nm)) composed of the compounds shown in Table 2. Otherwise, an element was obtained and evaluated in the same manner as in Example 6. The results are shown in Table 2.
In the table, the hole transport layer 1 is on the anode side.

  From Tables 1 and 2, it can be seen that even if the element of the present invention has only one hole transport layer, the luminous efficiency is not greatly reduced and the lifetime is long.

DESCRIPTION OF SYMBOLS 1 Organic EL element 10 Anode 20 Cathode 30 Light emitting layer 40 Hole transport zone 41 Hole injection layer 43 Hole transport layer 50 Electron transport zone

Claims (26)

Opposing anode and cathode;
A light emitting layer provided between the anode and the cathode;
A hole transport zone formed between the anode and the light emitting layer,
The hole transport zone consists of only one hole transport layer in contact with the light emitting layer and one hole injection layer in contact with the anode,
The hole transport layer includes a compound represented by the following formula (1),
The hole injection layer includes 2 to 6 aromatic six-membered rings and a connecting portion that includes the structure represented by the following formula (2a) or (2b) and connects the aromatic six-membered rings. Each of the aromatic six-membered rings is a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aryl group, substituted or unsubstituted Substituted heterocyclic group, halogen atom, substituted or unsubstituted fluoroalkyl group, substituted or unsubstituted alkoxy group, substituted or unsubstituted fluoroalkoxy group, substituted or unsubstituted aryloxy group, substituted or unsubstituted aralkyloxy The organic electroluminescent element containing the compound which may be substituted by group, a substituted or unsubstituted amino group, or a cyano group.

(In the formula (1), Ar ¹ and Ar ² are each a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group. L is a single bond, a substituted or unsubstituted arylene group, Or a substituted or unsubstituted heteroarylene group, wherein R ^{61 to} R ⁶³ are each a substituent, k is an integer of 0 to 5, m is an integer of 0 to 4, and n is 0 to 0. It is an integer of 3.)

(Formula (2b) ^{in, X 20} is represented by any one of the following formulas (2b-1) ~ (2b -12).)

(In the formulas (2b-1) to (2b-12), R ²⁰ is a hydrogen atom, a substituted or unsubstituted fluoroalkyl group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted group, respectively. Or an unsubstituted heterocyclic group.) In the formula (1), R ⁶¹ represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, a halogen atom, a substituted or unsubstituted carbon number of 1 -20 fluoroalkyl group, substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, substituted or unsubstituted fluoroalkoxy group having 1 to 20 carbon atoms, or cyano group, and a plurality of R ⁶¹ are present The plurality of R ⁶¹ may be the same or different from each other;
R ⁶² and R ⁶³ are each a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, a substituted or unsubstituted ring atom having 3 to 50 ring atoms. A heterocyclic group, a halogen atom, a substituted or unsubstituted fluoroalkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted fluoroalkoxy group having 1 to 20 carbon atoms group, a substituted or unsubstituted ring aryloxy group having 6 to 50 carbon atoms, or a cyano group, and if R ⁶² there are a plurality, R ⁶² of the plurality of may be the same or different, R ⁶³ A plurality of R ⁶³ may be the same or different,
The organic electroluminescent element according to claim 1. In Formula (1), Ar < ¹ > and Ar < ² > are groups selected from following formula (11)-(19), respectively, The organic electroluminescent element of Claim 1 or 2.

(In the formula ^{(11) ~ (19),} R 61, k, m, n are the same ^R 61, k of formula (1), m, and n.
X ′ is an oxygen atom or a sulfur atom.
L ¹ is the same as L in formula (1),
R ⁷¹ is a hydrogen atom or the same group as R ⁶¹ .
R ⁷³ and R ⁷⁵ are the same as R ⁶² and R ^{63 in} the formula (1). However, R ⁷³ and R ⁷⁵ may form a ring.
In the formula (11), R ⁶¹ may be bonded to any position of the carbazole skeleton, and L ¹ may be bonded to any position of the carbazole skeleton.
In the formula (13), R ⁶¹ may be bonded to any position of the dibenzofuran skeleton or the dibenzothiophene skeleton, and may be bonded to any position of the L ¹ dibenzofuran skeleton or the dibenzothiophene skeleton.
In the formulas (12) and (14) to (19), R ⁶¹ may be bonded to any position of the benzene ring, and L ¹ may be bonded to any position of the benzene ring. ) The organic electroluminescent device according to claim 3, wherein at least one of Ar ¹ and Ar ² is represented by formula (11). The organic electroluminescence device according to claim 3, wherein at least one of Ar ¹ and Ar ² is represented by formula (12). The organic electroluminescent element according to claim 3, wherein at least one of Ar ¹ and Ar ² is represented by formula (13). The organic electroluminescent element according to claim 3, wherein at least one of Ar ¹ and Ar ² is represented by formula (14). The organic electroluminescent element according to claim 3, wherein at least one of Ar ¹ and Ar ² is any one of formulas (15) to (19). The organic electroluminescence device according to claim 3 or 4, wherein the group represented by the formula (11) is the following group in which L ¹ is bonded at the 3-position of the carbazole skeleton.

The organic electroluminescent device according to claim 3 or 6, wherein the group represented by the formula (13) and L ¹ are the following groups bonded at the 4-position of the dibenzofuran skeleton or the dibenzothiophene skeleton.

  The organic electroluminescence device according to claim 3 or 8, wherein Formula (16) is bonded to the nitrogen atom of Formula (1) at the para position.   The organic electroluminescence device according to claim 3 or 8, wherein the formula (17) is bonded to the nitrogen atom of the formula (1) at the ortho position. In Formula (1), L is group represented by following formula (20), The organic electroluminescent element in any one of Claims 1-12.

(In the formula ^{(20), R 61, m} , n , when the same as ^R 61, m, n of formula (1) .n is zero, the plurality when L is a single bond .n is more And R ⁶¹ , m may be the same or different, and R ⁶¹ may be bonded to each other to form a ring.)   The organic electroluminescent device according to claim 13, wherein in formula (20), when n is plural, n benzene rings are bonded to each other at the para position.   The organic electroluminescent device according to claim 13, wherein n is 1 or 2 in the formula (20).   The organic electroluminescence device according to any one of claims 1 to 15, wherein in the compound of the hole injection layer, each of the aromatic 6-membered rings is a hydrocarbon ring or a heterocyclic ring containing nitrogen.   The compound of the said positive hole injection layer WHEREIN: The connection part containing the structure represented by said (2b) forms the 5-membered ring condensed with two 6 aromatic member rings to connect. The organic electroluminescent element of description. The organic electroluminescence device according to any one of claims 1 to 16, wherein the compound of the hole injection layer is represented by the following formula (2).

(In formula (2), each X is a group represented by the following formula.
R ²⁰⁰ -C ^* -CN
(In the above formula, C ^* is a carbon atom bonded to the cyclopropane of the formula (2) by a double bond.
R ²⁰⁰ is an aromatic 6-membered ring substituted with one or more selected from an aromatic 6-membered ring, a halogen atom, a substituted or unsubstituted fluoroalkyl group, a substituted or unsubstituted fluoroalkoxy group, and a cyano group, respectively. It is a ring. ) R ^{200 in the} formula (2) is a perfluoropyridin-4-yl group, a tetrafluoro-4- (trifluoromethyl) phenyl group, a 4-cyanoperfluorophenyl group, a dichloro-3,5-difluoro-4- (trifluoro). The organic electroluminescent device according to claim 18, which is a methyl) phenyl group or a perfluorophenyl group.   The compound of formula (2) is (2E, 2′E, 2 ″ E) -2,2 ′, 2 ″-(cyclopropane-1,2,3-triylidene) tris (2- (perfluorophenyl) -Acetonitrile), (2E, 2'E, 2 "E) -2,2 ', 2"-(cyclopropane-1,2,3-triylidene) tris (2- (perfluoropyridin-4-yl) -Acetonitrile), (2E, 2'E, 2 "E) -2,2 ', 2"-(cyclopropane-1,2,3-triylidene) tris (2- (4-cyanoperfluorophenyl)- Acetonitrile), (2E, 2′E, 2 ″ E) -2,2 ′, 2 ″-(cyclopropane-1,2,3-triylidene) tris (2- (2,3,5,6- Tetrafluoro-4- (trifluoromethyl) phenyl) -acetonitrile Or (2E, 2′E, 2 ″ E) -2,2 ′, 2 ″-(cyclopropane-1,2,3-triylidene) tris (2- (2,6-dichloro-3, The organic electroluminescent device according to claim 18, which is 5-difluoro-4- (trifluoromethyl) phenyl) -acetonitrile). The organic electroluminescence device according to any one of claims 1 to 16, wherein the compound of the hole injection layer is represented by the following formula (3).

(In Formula (3), Ar ¹ is a substituted or unsubstituted monocyclic or condensed ring having 6 to 24 ring carbon atoms or a heterocyclic ring having 6 to 24 ring atoms.
ar ¹ and ar ² are respectively the following formulas (i) or (ii).

(In formulas (i) and (ii), X ¹ and X ² are the same as X ^{20 in} formula (2b).)
R ^{1 to} R ⁴ are each a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 20 carbon atoms, a substituted or unsubstituted carbon number 1 to 20 alkenyl groups, substituted or unsubstituted aryl groups having 6 to 50 ring carbon atoms, substituted or unsubstituted heterocyclic groups having 3 to 50 ring atoms, halogen atoms, substituted or unsubstituted 1 to 20 carbon atoms Fluoroalkyl group, substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, substituted or unsubstituted fluoroalkoxy group having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy group having 6 to 50 ring carbon atoms, substituted Alternatively, it is an unsubstituted aralkyloxy group having 7 to 70 carbon atoms, a substituted or unsubstituted amino group, or a cyano group. R ¹ and R ² and R ³ and R ⁴ may be bonded to each other to form a saturated or unsaturated divalent group constituting a ring.
Y ^{1 to} Y ⁴ may be the same as or different from each other, and are —N═, —CH═, or —C (R ⁵ ) ═, and R ⁵ is the same as R ^{1 to} R ⁴ . R ^{1 to} R ⁵ adjacent to each other may be bonded to each other to form a saturated or unsaturated divalent group constituting a ring. ) The organic electroluminescence device according to claim 21, wherein the formula (3) is any one of the following formulas (I) to (IX).

(In formulas (I) to (IX), X ¹ and X ² , R ^{1 to} R ⁴ and R ^{8 to} R ¹⁷ are the same as X ¹ and X ² in formula (3), R ^{1 to} R ⁴ , Y ^{5 to} Y ¹⁰ , Y ^{11 to} Y ¹⁴ , Y ^{21 to} Y ²⁶ and Y ^{31 to} Y ³⁸ are the same as Y ^{1 to} Y ⁴ in the formula (3).) The organic electroluminescence device according to claim 22, wherein in formulas (I) to (IX), at least one of Y ^{1 to} Y ⁴ , Y ^{21 to} Y ²⁶ , and Y ^{31 to} Y ³⁸ is a nitrogen atom. In formulas (I) to (IX), at least one of R ^{1 to} R ⁴ is selected from a fluorine atom, a fluoroalkyl group, a fluoroalkoxy group, a cyano group, or fluorine, a fluoroalkyl group, a fluoroalkoxy group, and a cyano group. 24. The organic electroluminescence device according to claim 22 or 23, which is an aryl group or heterocyclic group having at least one group to be synthesized. Forming an anode;
Forming a hole injection layer;
Forming a hole transport layer; and
Forming a light emitting layer;
Forming a cathode, and
The step of forming another layer is not included between the step of forming the anode and the step of forming the hole injection layer.
Between the step of forming the hole transport layer and the step of forming the light emitting layer, a step of forming another layer is not included.
The manufacturing method of the organic electroluminescent element of Claim 1.   The display apparatus or light-emitting device which comprises the organic electroluminescent element in any one of Claims 1-24.

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