KR101867767B1 - Organic electroluminescence device and charge transport material - Google Patents

Abstract

식 중, R₁ ∼ R₈ 은 각각 독립적으로 수소 원자, 알킬기, 아릴기, 헤테로아릴기 또는 전자 구인성기를 나타낸다. 단, R₁ ∼ R₈ 중 적어도 1 개는 전자 구인성기이다. 상기 전자 구인성기는 시아노기, 니트로기, 퍼플루오로알킬기 또는 할로겐 원자이다. R_1a 및 R_1b 는 각각 독립적으로 알킬기, 알콕시기, 아릴기, 헤테로아릴기, 시아노기, 니트로기, 할로겐 원자 또는 아미노기를 나타낸다. n_1a 및 n_1b 는 각각 독립적으로 0 ∼ 4 의 정수를 나타낸다.) assignment
A high number of organic electroluminescent devices excellent in current independence of external quantum efficiency, durability and chromaticity, and a charge transporting material useful for the organic electroluminescent device.
Solution
An organic electroluminescent device comprising, on a substrate, a pair of electrodes and at least one organic layer including a light emitting layer between the electrodes, wherein the organic layer contains at least one compound represented by the general formula (1).

In the formulas, R ₁ to R ₈ each independently represent a hydrogen atom, an alkyl group, an aryl group, a heteroaryl group or an electron-attracting group. Provided that at least one of R ₁ to R ₈ is an electron-withdrawing group. The electron-attractive group is a cyano group, a nitro group, a perfluoroalkyl group or a halogen atom. R _1a and R _1b each independently represent an alkyl group, an alkoxy group, an aryl group, a heteroaryl group, a cyano group, a nitro group, a halogen atom or an amino group. n _1a and n _1b Each independently represent an integer of 0 to 4.)

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an organic electroluminescent device and an organic electroluminescent device,

The present invention relates to an organic electroluminescent element (hereinafter, also referred to as an "element" or "organic EL element"), and more particularly to an organic electroluminescent element having excellent performance of various elements (specifically, external quantum efficiency, durability, And more particularly to an organic electroluminescent device having a high number of organic electroluminescent devices. The present invention also relates to a charge transport material useful for an organic electroluminescent device.

BACKGROUND ART Organic electroluminescent devices have been actively researched and developed in recent years in that high-luminance light emission can be obtained by driving at a low voltage. In general, an organic electroluminescent device is composed of an organic layer including a light emitting layer and a pair of electrodes sandwiching the organic layer, and electrons injected from the cathode and holes injected from the anode are recombined in the light emitting layer to generate exciton energy Is used for light emission.

In recent years, the use of a phosphorescent material has led to higher efficiency of the device. In addition, a doped device using a light emitting layer doped with a light emitting material into a host material is widely used.

For example, in Patent Documents 1 to 3, iridium complex, platinum complex or the like is used as a phosphorescent light-emitting material, and a compound having a specific structure including a nitrogen-containing heterocyclic group and a carbazole structure is used as a host material, An organic electroluminescent device having improved durability has been proposed.

On the other hand, in Patent Document 4, by using a biphenyl compound having a carbazolyl group at the 4-position of biphenyl and a carbazolyl group or a diarylamino group at the 3 'position as an electron transporting material, An organic electroluminescent device improved in lifetime is disclosed. Patent Document 5 also discloses an organic electroluminescent device improved in heat resistance and luminescence brightness by using an electron transporting material having a carbazole skeleton.

WO 05/085387 WO 03/080760 WO 03/078541 Japanese Laid-Open Patent Publication No. 2009-64918 Japanese Laid-Open Patent Publication No. 2005-116247

However, the conventional device has a problem that the half-life time is shortened when driven with a high luminance, the durability is poor, and the chromaticity is changed due to the difference in current in the light-emitting layer.

The present invention has been made in view of the above problems in the conventional organic electroluminescent device, and it is an object of the present invention to provide a high number of organic electroluminescent devices excellent in external quantum efficiency, durability, And to provide a charge transporting material useful for a light emitting device. Another object of the present invention is to provide a light emitting device, a display device, and a lighting device including the organic electroluminescent device.

The inventors of the present invention have found that the above object can be achieved by using a compound having a low symmetry in which a carbazole skeleton is bonded at a meta position and a para position as an electron transporting material. .

That is, since the compound having low symmetry is suppressed in crystallinity, the difference in energy between charge transporting paths is small, and therefore, it is considered that the charge transportability is excellent and the charge injectability is high. In the EL element, the contribution of charge injection becomes small at the high current value side, and the balance of both carriers changes in the light emitting layer due to the change of the luminescent position, thereby changing the chromaticity. However, by introducing an electron- This chromaticity change can be suppressed by using the compound whose injection property is increased. Further, according to the compound, an EL element having an excellent external quantum efficiency and a long half-life time when driven at a high luminance is obtained.

That is, the present invention has been achieved by the following means.

[1] An organic electroluminescent device comprising, on a substrate, a pair of electrodes and at least one organic layer including a light emitting layer between the electrodes,

Wherein the organic layer contains at least one compound represented by the general formula (1).

(In the general formula (1), R ₁ to R ₈ each independently represent a hydrogen atom, an alkyl group, an aryl group, a heteroaryl group or an electron-attracting group, provided that at least one of R ₁ to R ₈ is an electron- R _1a and R _1b each independently represent an alkyl group, an alkoxy group, an aryl group, a heteroaryl group, a cyano group, a nitro group, a halogen atom, a halogen atom, N _1a and n _1b each independently represent an integer of 0 to 4.)

[2] The organic electroluminescent device according to [1], wherein at least one of R ₁ to R ₈ in the general formula (1) represents a cyano group.

[3] The organic electroluminescent device according to [2], wherein the compound represented by the general formula (1) is a compound represented by the general formula (2).

(In the general formula (2), R _2a and R _2b each independently represent an alkyl group, an aryl group, a heteroaryl group, a cyano group or a halogen atom, and n _2a and n _2b each independently represent an integer of 0 to 2 .)

[4] The organic electroluminescent device according to [3], wherein the compound represented by the general formula (2) is a compound represented by the general formula (3).

(In the general formula (3), R _3a to R _3d each independently represent a hydrogen atom, an alkyl group, an aryl group, a heteroaryl group, a cyano group or a halogen atom.)

[5] The organic electroluminescent device according to any one of [1] to [4], wherein the light emitting layer contains at least one compound represented by the general formula (1).

[6] The organic electroluminescent device according to [5], wherein the light-emitting layer further contains a phosphorescent metal complex.

[7] The organic electroluminescent device according to [6], wherein the phosphorescent metal complex is an iridium complex.

[8] The organic electroluminescent device according to [7], wherein the iridium complex is an iridium complex represented by the general formula (T-2).

Wherein R _T3 'to R _T6 ' and R _T3 to R _T6 each independently represent a hydrogen atom, vinyl group _{fluoro, -CO 2 R T, -C (} O) R T, -N (R T) 2, -NO 2, -OR T, a halogen atom, an aryl group or a heteroaryl group, a substituent in more Z .

R _T3 , R _T4 , R _T5 and R _T6 may be bonded to each other to form a condensed 4- to 7-membered ring, and the condensed 4- to 7-membered ring may further have a substituent Z.

R _T3 'and _T6 R is _{-C (R T) 2 -C (} R T) 2 -, -CR T = CR T -, -C (R T) 2 -, -O-, -NR T -, - May be linked by a linking group selected from OC (R _T ) ₂ -, -NR _T -C (R _T ) ₂ - and -N = CR _T - to form a ring.

R _T each independently represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, a heteroalkyl group, an aryl group or a heteroaryl group, and may further have a substituent Z.

Z is a halogen atom, each independently, -R ', -OR', -N (R ') 2, -SR', -C (O) R ', -C (O) OR', -C (O) N _{(R ') 2, -CN,} -NO 2, -SO 2, -SOR', -SO ₂ R represents a 'or -SO ₃ R', R 'are each independently a hydrogen atom, an alkyl, perhaloalkyl, An alkenyl group, an alkynyl group, a heteroalkyl group, an aryl group or a heteroaryl group.

(XY) represents a subsidiary ligand. m _T represents an integer of 1 to 3, and n _T represents an integer of 0 to 2. m _T + n _T is 3.)

[9] The organic electroluminescent device according to the above [8], wherein in the general formula (T-2), (X-Y) is a monoanionic bidentate ligand having a phenylpyridine skeleton.

[10] The organic electroluminescent device according to any one of [1] to [9], wherein an organic layer adjacent to the light emitting layer is provided between the light emitting layer and the cathode, and the organic layer contains an aromatic hydrocarbon compound.

[11] The organic electroluminescent device described in any one of [1] to [10], wherein the organic layer contains at least one compound represented by the following formula (O-1) Lt; / RTI >

(In the formula (O-1), R ^O1 represents an alkyl group, an aryl group or a heteroaryl group, A ^O1 to A ^O4 each independently represent a CR ^A or a nitrogen atom, R ^A represents a hydrogen atom, an alkyl group, Or a heteroaryl group, and plural R ^A may be the same or different, L ^O1 represents a divalent to 6-valent linking group consisting of an aryl ring or a heteroaryl ring, and n ^O1 represents an integer of 2 to 6.)

[12] The organic electroluminescent device according to any one of [1] to [11], wherein at least one of the organic layers is formed by a solution coating process.

[13] A light emitting device using the organic electroluminescent device described in any one of [1] to [12] above.

[14] A display device using the organic electroluminescent element described in any one of [1] to [12] above.

[15] An illumination device using the organic electroluminescent device according to any one of [1] to [12].

[16] A charge-transporting material represented by the general formula (1).

(In the general formula (1), R ₁ to R ₈ each independently represent a hydrogen atom, an alkyl group, an aryl group, a heteroaryl group or an electron-attracting group, provided that at least one of R ₁ to R ₈ is an electron- R _1a and R _1b each independently represent an alkyl group, an alkoxy group, an aryl group, a heteroaryl group, a cyano group, a nitro group, a halogen atom, a halogen atom, N _1a and n _1b each represent an integer of 0 to 4.)

[17] The charge-transporting material according to the above-mentioned [16], wherein the charge-transporting material represented by the general formula (1) is a charge-transporting material represented by the general formula (2).

(In the general formula (2), R _2a and R _2b each independently represent an alkyl group, an aryl group, a heteroaryl group, a cyano group or a halogen atom, and n _2a and n _2b each independently represent an integer of 0 to 2 .)

[18] A light-emitting layer containing the charge-transporting material according to the above [16] or [17].

According to the present invention, it is possible to provide a high number of organic electroluminescent devices excellent in external quantum efficiency, durability and chromaticity and current independence, and a charge transporting material useful for the organic electroluminescent device. Further, a light emitting device, a display device, and a lighting device including the organic electroluminescent device can be provided.

Fig. 1 is a schematic view showing an example (first embodiment) of the layer structure of the organic EL device according to the present invention.
2 is a schematic view showing an example (second embodiment) of a light emitting device related to the present invention.
3 is a schematic view showing an example (third embodiment) of the lighting apparatus according to the present invention.

The hydrogen atoms in the following description of the general formulas (1) to (3) also include isotopes (deuterium atoms, etc.), and the atoms constituting the substituents also include isotopes thereof. In this case, all of the hydrogen atoms in the compound may be substituted with isotopes, or a mixture of compounds in which some of the hydrogen atoms are contained.

In the present invention, when a "substituent" is mentioned, the substituent may be substituted. For example, the term " alkyl group " in the present invention includes an alkyl group substituted with a fluorine atom (e.g., trifluoromethyl group) or an alkyl group substituted with an aryl group (e.g., triphenylmethyl group) Quot; denotes an alkyl group having 1 to 6 carbon atoms ", all groups including a substituted group indicate 1 to 6 carbon atoms.

In the present invention, substituent group A, substituent group B and substituent Z 'are defined as follows.

(Substituent group A)

(Preferably having 1 to 30 carbon atoms, more preferably 1 to 20 carbon atoms, and particularly preferably 1 to 10 carbon atoms, such as methyl, ethyl, isopropyl, tert-butyl, n-octyl, , an alkenyl group (preferably having 2 to 30 carbon atoms, more preferably 2 to 20 carbon atoms, particularly preferably 2 to 10 carbon atoms) such as methyl, ethyl, propyl, isopropyl, (Preferably having 2 to 30 carbon atoms, more preferably 2 to 20 carbon atoms, particularly preferably 1 to 20 carbon atoms, and examples thereof include vinyl, allyl, 2-butenyl and 3-pentenyl) (Preferably having 6 to 30 carbon atoms, more preferably 6 to 20 carbon atoms, particularly preferably a carbon number < RTI ID = 0.0 > 6 to 12, for example, phenyl, p-methylphenyl, naphthyl, anthranyl, etc. (Preferably having 0 to 30 carbon atoms, more preferably 0 to 20 carbon atoms, particularly preferably 0 to 10 carbon atoms, such as amino, methylamino, dimethylamino, diethylamino, dibenzyl (Preferably having 1 to 30 carbon atoms, more preferably 1 to 20 carbon atoms, particularly preferably 1 to 10 carbon atoms, such as amino, diphenylamino and ditolylamino), an alkoxy group (Preferably having 6 to 30 carbon atoms, more preferably 6 to 20 carbon atoms, and particularly preferably 6 carbon atoms, such as methoxy, ethoxy, butoxy, 2-ethylhexyloxy and the like) (Preferably 1 to 30 carbon atoms, more preferably 1 to 20 carbon atoms, and more preferably 1 to 20 carbon atoms), such as phenyloxy, 1-naphthyloxy and 2-naphthyloxy), a heterocyclic oxy group , Particularly preferably having 1 to 12 carbon atoms, such as pyridyl (Preferably having 2 to 30 carbon atoms, more preferably 2 to 20 carbon atoms, particularly preferably 2 to 12 carbon atoms), an aryloxy group (e.g., , An alkoxycarbonyl group (preferably having 2 to 30 carbon atoms, more preferably 2 to 20 carbon atoms, particularly preferably 2 to 12 carbon atoms) such as acetyl, benzoyl, formyl, pivaloyl, An aryloxycarbonyl group (preferably having 7 to 30 carbon atoms, more preferably 7 to 20 carbon atoms, and particularly preferably 7 to 20 carbon atoms), an aryloxycarbonyl group (preferably having 7 to 30 carbon atoms, more preferably 7 to 20 carbon atoms, (Preferably 2 to 30 carbon atoms, more preferably 2 to 20 carbon atoms, particularly preferably 2 to 10 carbon atoms, and examples thereof include phenyloxycarbonyl and the like), an acyloxy group For example, acetoxy, benzoyloxy and the like, And an acylamino group (preferably having 2 to 30 carbon atoms, more preferably 2 to 20 carbon atoms, and particularly preferably 2 to 10 carbon atoms, such as acetylamino and benzoylamino). ), An alkoxycarbonylamino group (preferably having 2 to 30 carbon atoms, more preferably 2 to 20 carbon atoms, particularly preferably 2 to 12 carbon atoms, such as methoxycarbonylamino) An aryloxycarbonylamino group (preferably having 7 to 30 carbon atoms, more preferably 7 to 20 carbon atoms, and particularly preferably 7 to 12 carbon atoms, such as phenyloxycarbonylamino) A sulfonylamino group (preferably having 1 to 30 carbon atoms, more preferably 1 to 20 carbon atoms, and particularly preferably 1 to 12 carbon atoms, such as methanesulfonylamino and benzenesulfonylamino) alcohol (Preferably having 0 to 30 carbon atoms, more preferably 0 to 20 carbon atoms, and particularly preferably 0 to 12 carbon atoms, such as sulfamoyl, methylsulfamoyl, dimethylsulfamoyl, phenylsulfamoyl, etc.) (Preferably having 1 to 30 carbon atoms, more preferably 1 to 20 carbon atoms, and particularly preferably 1 to 12 carbon atoms, such as carbamoyl, methylcarbamoyl, diethyl (Preferably having 1 to 30 carbon atoms, more preferably 1 to 20 carbon atoms, and particularly preferably 1 to 12 carbon atoms, such as, for example, (Preferably having 6 to 30 carbon atoms, more preferably 6 to 20 carbon atoms, and particularly preferably 6 to 12 carbon atoms, such as phenylthio, etc.) ), A heterocyclic thio group (Preferably having 1 to 30 carbon atoms, more preferably 1 to 20 carbon atoms, and particularly preferably 1 to 12 carbon atoms, such as pyridylthio, 2-benzimidazolylthio, 2-benzoxazolylthio, (Preferably having 1 to 30 carbon atoms, more preferably 1 to 20 carbon atoms, and particularly preferably 1 to 12 carbon atoms, such as mesyl, tosyl, , A sulfinyl group (preferably having 1 to 30 carbon atoms, more preferably 1 to 20 carbon atoms, and particularly preferably 1 to 12 carbon atoms, such as methanesulfinyl, benzenesulfinyl, etc.) (Preferably having 1 to 30 carbon atoms, more preferably 1 to 20 carbon atoms, and particularly preferably 1 to 12 carbon atoms, such as ureido, methylureido, phenylureido, etc.) ), A phosphoric acid amide group (preferably, (Preferably 1 to 30 carbon atoms, more preferably 1 to 20 carbon atoms, and particularly preferably 1 to 12 carbon atoms, such as diethylphosphoric acid amide and phenylphosphoric acid amide), hydroxyl groups, mercapto groups , A halogen atom (e.g., fluorine atom, chlorine atom, bromine atom, iodine atom), cyano group, sulfo group, carboxyl group, nitro group, Preferably 1 to 30 carbon atoms, more preferably 1 to 12 carbon atoms, and the hetero atom includes, for example, a nitrogen atom, an oxygen atom, a sulfur atom, a phosphorus atom, a silicon atom, Atom and tellurium atom and specifically exemplified by pyridyl, pyrazinyl, pyrimidyl, pyridazinyl, pyrrolyl, pyrazolyl, triazolyl, imidazolyl, oxazolyl, thiazolyl, isoxazolyl, isothiazolyl, Quinolyl, furyl, thia , Selenophenyl, telulophenyl, piperidyl, piperidino, morpholino, pyrrolidyl, pyrrolidino, benzoxazolyl, benzimidazolyl, benzothiazolyl, carbazolyl group, azepinyl group A silyl group (preferably having 3 to 40 carbon atoms, more preferably 3 to 30 carbon atoms, and particularly preferably 3 to 24 carbon atoms, such as trimethylsilyl, triphenylsilyl , A silyloxy group (preferably having 3 to 40 carbon atoms, more preferably 3 to 30 carbon atoms, and particularly preferably 3 to 24 carbon atoms, such as trimethylsilyloxy, triphenylsilyloxy And the like), a phosphoryl group (for example, a diphenylphosphoryl group, a dimethylphosphoryl group, etc.). These substituents may be further substituted, and examples of the additional substituent include groups selected from the substituent group A described above.

(Substituent group B)

(Preferably having 1 to 30 carbon atoms, more preferably 1 to 20 carbon atoms, and particularly preferably 1 to 10 carbon atoms, such as methyl, ethyl, isopropyl, tert-butyl, n-octyl, , an alkenyl group (preferably having 2 to 30 carbon atoms, more preferably 2 to 20 carbon atoms, particularly preferably 2 to 10 carbon atoms) such as methyl, ethyl, propyl, isopropyl, (Preferably having 2 to 30 carbon atoms, more preferably 2 to 20 carbon atoms, particularly preferably 1 to 20 carbon atoms, and examples thereof include vinyl, allyl, 2-butenyl and 3-pentenyl) (Preferably having 6 to 30 carbon atoms, more preferably 6 to 20 carbon atoms, particularly preferably a carbon number < RTI ID = 0.0 > 6 to 12, for example, phenyl, p-methylphenyl, naphthyl, anthranyl, etc. (Preferably having 1 to 30 carbon atoms, more preferably 1 to 12 carbon atoms, and the heteroatom includes, for example, a nitrogen atom, an oxygen atom, a sulfur atom), a cyano group or a heterocyclic group (including an aromatic heterocyclic group) A heterocyclic group, an oxygen atom, a phosphorus atom, a silicon atom, a selenium atom, , Isoxazolyl, isothiazolyl, quinolyl, furyl, thienyl, selenophenyl, telulophenyl, piperidyl, piperidino, morpholino, pyrrolidyl, pyrrolidino, benzoxazolyl, benzo An imidazolyl group, a benzothiazolyl group, a carbazolyl group, an azepinyl group, and a silyl group). These substituents may be further substituted, and examples of the additional substituent include groups selected from the substituent group A. [

(Substituent Z ')

An alkyl group (preferably having 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, and still more preferably 1 to 4 carbon atoms, such as a methyl group, an ethyl group, an isopropyl group, (Preferably having 3 to 10 carbon atoms, more preferably 4 to 7 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, (Preferably having 2 to 8 carbon atoms, more preferably 2 to 8 carbon atoms, more preferably 2 or 3 carbon atoms, and more preferably 5 or 6 carbon atoms, such as cyclopropyl group, cyclopentyl group and cyclohexyl group) 6, such as vinyl), an aryl group (having 6 to 30 carbon atoms, and more preferably 6 to 20 carbon atoms, such as a phenyl group, a naphthyl group, an anthracenyl group, a tetracenyl group, A perylenyl group, a triphenylenyl group, and a chrysenyl group), Hetero (Preferably having 4 to 30 carbon atoms, more preferably 4 to 20 carbon atoms, and still more preferably 5 to 10 carbon atoms, such as pyridine, pyrazine, pyrimidine, pyridazine, triazine, thiophene, furan , An alkoxyl group (preferably having 1 to 8 carbon atoms, more preferably 1 to 4 carbon atoms, and more preferably 1 to 4 carbon atoms), an alkoxycarbonyl group A halogen atom (preferably a fluorine atom), a silyl group (preferably a fluorine atom), a fluorine atom (preferably a fluorine atom) (Preferably having 2 to 60 carbon atoms, more preferably 4 to 30 carbon atoms, more preferably 4 to 20 carbon atoms, such as a trimethylsilyl group, a triethylsilyl group, and a triphenylsilyl group) 2 to 40, and examples thereof include a dimethylamino group, a diethylamino group, There may be mentioned an amino group, etc.), a cyano group or represents a group formed by combining them, the plurality of substituents Z 'may form an aryl ring bonded to each other. Examples of the aryl ring formed by bonding a plurality of substituents Z 'to each other include a phenyl ring and a pyridine ring, and a phenyl ring is preferable.

(Organic electroluminescent device)

An organic electroluminescent device according to the present invention is an organic electroluminescent device having a pair of electrodes on a substrate and at least one organic layer including a light emitting layer between the electrodes, 1).

The compound represented by the general formula (1) may be contained in the light emitting layer contained in the organic layer. The light emitting layer may include a phosphorescent metal complex.

Further, an adjacent layer adjacent to the light emitting layer may be provided between the light emitting layer and the cathode, and the adjacent layer may contain an aromatic hydrocarbon compound.

[Compound represented by the general formula (1)]

Hereinafter, the compound represented by the general formula (1) will be described.

(In the general formula (1), R ₁ to R ₈ each independently represent a hydrogen atom, an alkyl group, an aryl group, a heteroaryl group or an electron-attracting group, provided that at least one of R ₁ to R ₈ is an electron- R _1a and R _1b each independently represent an alkyl group, an alkoxy group, an aryl group, a heteroaryl group, a cyano group, a nitro group, a halogen atom, a halogen atom, N _1a and n _1b each independently represent an integer of 0 to 4.)

In the general formula (1), R ₁ to R ₈ each independently represent a hydrogen atom, an alkyl group, an aryl group, a heteroaryl group or an electron-attracting group. Provided that at least one of R ₁ to R ₈ is an electron-withdrawing group. This electron-attracting group is selected from a cyano group, a nitro group, a perfluoroalkyl group and a halogen atom.

The alkyl group represented by R ₁ to R ₈ is preferably an alkyl group having 1 to 6 carbon atoms, more preferably an alkyl group having 1 to 4 carbon atoms, and may have a substituent. As the substituent in the case of having a substituent, the above-mentioned substituent Z 'can be mentioned, and as the substituent Z', an aryl group is preferable. Examples of the alkyl group represented by R ₁ to R ₈ include a methyl group, an ethyl group, a n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec- Methylpentyl, 2-methylpentyl, 3,3-dimethylbutyl, 2,2-dimethylpentyl, 2-methylpentyl, 2-methylpentyl, Butyl group, a 1,1-dimethylbutyl group, a 1,2-dimethylbutyl group, a 1,3-dimethylbutyl group and a 2,3-dimethylbutyl group. Of these, methyl, ethyl, a t-butyl group and a neopentyl group are preferable, and a methyl group, an ethyl group and an isopropyl group are more preferable.

The aryl group represented by R ₁ to R ₈ may be substituted or may have a substituent. As the substituent in the case of having a substituent, the aforementioned substituent Z 'can be mentioned, and as the substituent Z', an alkyl group, a cycloalkyl group and an aryl group are preferable, and an alkyl group is more preferable. The aryl group represented by R ₁ to R ₈ is preferably an aryl group having 6 to 30 carbon atoms, more preferably an aryl group having 6 to 18 carbon atoms. The aryl group having 6 to 18 carbon atoms is preferably an aryl group having 6 to 18 carbon atoms and may have an alkyl group having 1 to 6 carbon atoms. Examples of the substituent include a phenyl group, a dimethylphenyl group, a diisopropylphenyl group, a dit-butylphenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a methylnaphthyl group, a t- butylnaphthyl group, an anthranyl group, a phenanthryl group, Dimethylphenyl group, biphenyl group, terphenyl group, naphthyl group, methylnaphthyl group, t-butylnaphthyl group and 9,9-dimethylfluorenyl group are preferable More preferably a phenyl group, a biphenyl group, or a terphenyl group, and most preferably a phenyl group, and most preferably a phenyl group, a dimethylphenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a methylnaphthyl group and a t-butylnaphthyl group.

The heteroaryl group represented by R ₁ to R ₈ may be a ring or may have a substituent. As the substituent in the case of having a substituent, the above-mentioned substituent Z 'can be mentioned, and as the substituent Z', an alkyl group, a cycloalkyl group and a phenyl group are preferable, and an alkyl group is more preferable. The heteroaryl group represented by R ₁ to R ₈ is preferably a heteroaryl group having 5 to 8 carbon atoms, more preferably a substituted or unsubstituted heteroaryl group having 5 or 6 atoms, such as a pyridyl group, a pyrazinyl group A pyridazinyl group, a pyrimidinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a quinazolinyl group, a cinnolinyl group, a phthalazinyl group, a quinoxalinyl group, a pyrrolyl group, A thiazolyl group, an oxazolyl group, a benzoyl group, a benzoyl group, a benzoyl group, a benzoyl group, a benzoyl group, a benzoyl group, A thiazolyl group, a thiazolyl group, a benzothiazolyl group, an isothiazolyl group, a benzisothiazolyl group, a thiadiazolyl group, an isoxazolyl group, a benzisoxazolyl group, a pyrrolidinyl group, a piperidinyl group, An imidazolidinyl group, a thiazolinyl group, a sulfora And preferred examples thereof include pyridyl, pyrazinyl, pyrimidinyl, triazinyl, quinolinyl, isoquinolinyl, pyrrolyl, indolyl, carbazolyl, furyl, A thienyl group, a benzothienyl group, a dibenzothienyl group, a pyrazolyl group, an imidazolyl group, or a benzimidazolyl group, more preferably a pyridyl group, a pyrimidinyl group, a quinolinyl group, Most preferably a pyridyl group, a carbazolyl group, a dibenzofuryl group, a dibenzofuryl group, a dibenzofuryl group, a dibenzofuryl group, an imidazolyl group, a dibenzofuryl group, Benzothienyl group.

The perfluoroalkyl group as an electron-withdrawing group represented by R ₁ to R ₈ is preferably a perfluoroalkyl group having 1 to 6 carbon atoms, more preferably a perfluoroalkyl group having 1 to 3 carbon atoms, and a trifluoromethyl group Is more preferable.

The halogen atom as an electron-withdrawing group represented by R ₁ to R ₈ includes, for example, a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, and is preferably a fluorine atom.

At least one of R ₁ to R ₈ is an electron-withdrawing group, and the electron-withdrawing group is preferably a cyano group, a perfluoroalkyl group or a halogen atom, more preferably a cyano group, a trifluoromethyl group or a fluorine atom, From the viewpoint of imparting the stability of the material to the charge, it is most preferable that it is a cyano group.

Each of R ₁ to R ₈ independently represents preferably a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an electron-withdrawing group. Provided that at least one of R ₁ to R ₈ is an electron-withdrawing group.

From the viewpoint of maintaining the ease of synthesis, four or more of R ₁ to R ₈ represent a hydrogen atom, and the remaining R ₁ to R ₈ each independently represents an alkyl group, an aryl group, a heteroaryl group, or an electron- , More preferably an alkyl group having 1 to 6 carbon atoms or an electron-attracting group. Provided that at least one of R ₁ to R ₈ is an electron-withdrawing group. From the viewpoint of further facilitating the synthesis, it is more preferable that at least 6 of R ₁ to R ₈ represent a hydrogen atom.

As at least one electron-attracting group for R ₁ to R ₈ , it is preferable that at least R ₄ is an electron-accepting group.

R _1a and R _1b are each independently an alkyl group, an alkoxy group, an aryl group, a heteroaryl group, a cyano group, a nitro group, a halogen atom or an amino group.

The alkyl groups represented by R _1a and R _1b each independently may have a substituent, and may be saturated or unsaturated. As the substituent in the case of having a substituent, the above-mentioned substituent Z 'can be mentioned, and the substituent Z' is preferably a fluorine atom. The alkyl group represented by R _1a and R _1b is preferably an alkyl group having 1 to 8 carbon atoms, more preferably an alkyl group having 1 to 6 carbon atoms. Examples of the alkyl group represented by R _1a and R _1b include a methyl group, a trifluoromethyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, An isopropyl group, a t-butyl group, a neopentyl group, a n-pentyl group, a n-pentyl group, -Hexyl group is preferable, and methyl group and t-butyl group are more preferable.

The alkoxy group represented by R _1a and R _1b is preferably an alkoxy group having 1 to 8 carbon atoms, more preferably an alkoxy group having 1 to 4 carbon atoms. Of these, a methoxy group, an ethoxy group, an iso-butyloxy group and a t-butyloxy group are preferable, a methoxy group and an ethoxy group are more preferable, and a methoxy group is more preferable.

The aryl group represented by R < _{1a >} and R < _1b > may be coordinated or may have a substituent. As the substituent in the case of having a substituent, the above-mentioned substituent Z 'can be mentioned, and as the substituent Z', an alkyl group and a phenyl group are preferable, and an alkyl group is more preferable. The aryl group represented by R _1a and R _1b is preferably an aryl group having 6 to 30 carbon atoms, more preferably an aryl group having 6 to 18 carbon atoms. The aryl group having 6 to 18 carbon atoms is preferably an aryl group having 6 to 18 carbon atoms, which may have an alkyl group having 1 to 6 carbon atoms, more preferably an aryl group having 6 to 18 carbon atoms, which may have an alkyl group having 1 to 4 carbon atoms . Examples of the substituent include a phenyl group, a dimethylphenyl group, a trimethylphenyl group, a diisopropylphenyl group, a t-butylphenyl group, a phenylphenyl group, a cyanophenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a methylnaphthyl group, Dimethylphenyl group, trimethylphenyl group, diisopropylphenyl group, t-butylphenyl group, phenylphenyl group, cyanophenyl group, naphthylphenyl group, A biphenyl group, a terphenyl group, a naphthyl group, a methylnaphthyl group and a t-butylnaphthyl group are preferable, and a phenyl group, a biphenyl group and a terphenyl group are more preferable, and a phenyl group is furthermore preferable.

The heteroaryl group represented by R < _{1a >} and R < _1b > may be coordinated or may have a substituent. As the substituent in the case of having a substituent, the above-mentioned substituent Z 'can be mentioned, and as the substituent Z', an alkyl group and a phenyl group are preferable, and an alkyl group is more preferable. The heteroaryl group represented by R _1a and R _1b is preferably a heteroaryl group having 5 to 8 carbon atoms, more preferably a substituted or unsubstituted heteroaryl group having 5 or 6 atoms, such as a pyridyl group, a pyrazinyl group A pyridazinyl group, a pyrimidinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a quinazolinyl group, a cinnolinyl group, a phthalazinyl group, a quinoxalinyl group, a pyrrolyl group, A thiazolyl group, a thiazolyl group, a benzothiazole group, a thiazolyl group, a thiazolyl group, a thiazolyl group, a thiazolyl group, a thiazolyl group, a benzothiazole group, A thiazolyl group, an isoxazolyl group, a benzisoxazolyl group, a pyrrolidinyl group, a piperidinyl group, a piperazinyl group, an imidazolidinyl group, an imidazolyl group, an imidazolyl group, A thiazolyl group, a sulfolanyl group and the like, and a pyridyl group, A carbazolyl group is preferred.

The halogen atom represented by R _1a and R _1b includes, for example, a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, and is preferably a fluorine atom.

The amino group represented by R _1a and R _1b may have a substituent. As the substituent in the case of having a substituent, the above-mentioned substituent Z 'can be mentioned, and as the substituent Z', an alkyl group or an aryl group is preferable, and an alkyl group is more preferable. The amino group represented by R _1a and R _1b is preferably an unsubstituted amino group, a dialkylamino group or a diarylamino group having 0 to 24 carbon atoms, more preferably a dialkylamino group or diarylamino group having 2 to 12 carbon atoms, and di The alkylamino group or the diarylamino group may form a ring structure. Specific examples thereof include an unsubstituted amino group, a dimethylamino group, a diethylamino group, a diphenylamino group, a dinaphthylamino group, a naphthylphenylamino group, an N-pyrrolidino group, an N-piperidino group, And a dimethylamino group, a diphenylamino group, a naphthylphenylamino group and an N-carbazolyl group are preferable.

As R _1a and R _1b , preferably an alkyl group, an aryl group, a heteroaryl group, a cyano group or a halogen atom, more preferably an alkyl group, an aryl group, a cyano group or a fluorine atom, more preferably from the viewpoint of chemical stability a t-butyl group, a phenyl group or a cyano group.

When a substituent is introduced into the carbazole skeleton, it is preferable to introduce a substituent at the 3-position or 6-position from the viewpoint of ease of synthesis and improvement of chemical stability, and the 3-position and 6-position of the carbazole skeleton are in the reaction active position.

n _1a and n _1b each independently represent an integer of 0 to 4, preferably an integer of 0 to 2, more preferably 0 or 1, and most preferably 0.

The compound represented by the general formula (1) is preferably a compound in which R ₁ to R ₃ and R ₅ to R ₈ are hydrogen atoms and R ₄ is a cyano group in the general formula (1). As such a compound, a compound represented by the general formula (2) can be mentioned.

(In the general formula (2), R _2a and R _2b each independently represent an alkyl group, an aryl group, a heteroaryl group, a cyano group or a halogen atom, and n _2a and n _2b each independently represent an integer of 0 to 2 .)

In the general formula (2), R _2a and R _2b each independently represent an alkyl group, an aryl group, a heteroaryl group, a cyano group or a halogen atom, preferably an alkyl group, an aryl group, a cyano group or a fluorine atom, a t-butyl group, a phenyl group or a cyano group.

Specific examples and preferred examples of the alkyl group, aryl group, heteroaryl group, cyano group and halogen atom represented by R _2a and R _2b are the same as those in R _1a and R _1b in the general formula (1).

n _2a and n _2b each independently represent an integer of 0 to 2, preferably 0 or 1, and most preferably 0.

The compound represented by the general formula (2) is preferably a compound represented by the general formula (3).

(In the general formula (3), R _3a to R _3d each independently represent a hydrogen atom, an alkyl group, an aryl group, a heteroaryl group, a cyano group or a halogen atom.)

In the general formula (3), R _3a to R _3d each independently represent a hydrogen atom, an alkyl group, an aryl group, a heteroaryl group, a cyano group or a halogen atom, and among these, a hydrogen atom, an alkyl group, an aryl group, Atom, more preferably a hydrogen atom, a t-butyl group, a phenyl group or a cyano group.

Specific examples and preferred examples of the alkyl group, aryl group, heteroaryl group, cyano group and halogen atom represented by R _3a to R _3d are the same as those in R _2a and R _2b in the general formula (2).

The present invention also relates to the charge-transporting materials represented by the above-mentioned general formulas (1) to (3). The charge-transporting material is a stable state as a radical anion or a radical cation, and is a material capable of transporting a charge when a voltage is applied to the material. It has been found that the materials represented by the general formulas (1) to (3) have a carbazole skeleton at a hole transporting site and are excellent in both charge transportability. Therefore, it is useful as a charge-transporting material. R ₁ to R ₈ , R _1a and R _1b , n _1a and n _1b , R _{2a in the} charge-transporting material represented by the general formulas (1) to (3) And R _2b , n _2a and n _2b and R _3a to R _3d are the same as those exemplified above, and preferable ones are also the same.

The molecular weight of the compound represented by the general formulas (1) to (3) is preferably 500 or more and 1000 or less, more preferably 500 or more and 800 or less, and more preferably 500 or more and 700 or less, so that the device film can be formed smoothly by vapor deposition. desirable.

The energy of the lowest excitation triplet (T ₁ ) in the film state of the compounds represented by the general formulas (1) to (3) is preferably 58 kcal / mol or more and 70 kcal / mol or less and more preferably 60 kcal / mol or more and 68 kcal / mol More preferably 60 kcal / mol or more and 65 kcal / mol or less.

T ₁ energy can be obtained from the short wavelength end by measuring the phosphorescent emission spectrum of the thin film as the material. For example, a material is deposited on a cleaned quartz glass substrate to a film thickness of about 50 nm by a vacuum evaporation method, and the phosphorescence emission spectrum of the thin film is measured with an F-7000 Hitachi spectrophotometer (Hitachi High- ). The T ₁ energy can be obtained by converting the rising wavelength of the obtained luminescence spectrum on the short wavelength side into energy units.

The glass transition temperature (Tg) of the compounds represented by the general formulas (1) to (3) is preferably from 50 캜 to 400 캜, more preferably from 75 캜 to 250 캜, further preferably from 80 캜 to 180 캜 Do.

Specific examples of the compounds represented by the general formulas (1) to (3) are illustrated below, but the present invention is not limited thereto.

The compounds exemplified as the compounds represented by the above general formulas (1) to (3) can be synthesized as follows. Most commonly, the carbazole compound is synthesized by dehydrogenation (LFTieze, Th.Eicher, Takano, Ogasawara translation, Precise Organic Synthesis) after azacophage reaction of a condensate of arylhydrazine and cyclohexane derivative , 339 pages (published by Nankodo)). The coupling reaction using the obtained carbazole compound and a halogenated aryl compound using a palladium catalyst is described in Tetrahedron Letters, vol. 39, p. 617 (1998), vol. 39, p. 2367 (1998) Page (1999), and the like. The reaction temperature and the reaction time are not particularly limited, and the conditions described in the above documents can be applied. After the synthesis, purification by column chromatography, recrystallization and the like is preferably carried out, and purification by sublimation purification is preferred. Not only the organic impurities can be separated by the sublimation purification, but also inorganic salts and residual solvents can be effectively removed.

In the present invention, the compounds represented by the general formulas (1) to (3) are not limited in their use and may be contained in any layer of the BR> A organic layer. Examples of the introduction layer of the compound represented by the general formulas (1) to (3) include a light emitting layer, a hole injecting layer, a hole transporting layer, an electron transporting layer, an electron injecting layer, an exciton blocking layer, desirable.

In the present invention, in order to further suppress the change in chromaticity depending on the current level, it is preferable that the compound represented by the general formulas (1) to (3) is contained in any of the luminescent layer or the layer adjacent to the luminescent layer, More preferable. The compounds represented by the general formulas (1) to (3) may be contained in both the light emitting layer and the adjacent layers.

When the compounds represented by the general formulas (1) to (3) are contained in the light emitting layer, the compounds represented by the general formulas (1) to (3) of the present invention are preferably contained in an amount of 0.1 to 99 mass% By mass, more preferably from 1 to 95% by mass, and still more preferably from 10 to 95% by mass. When the compound represented by any of the general formulas (1) to (3) is further contained in the layer other than the light-emitting layer, it is preferably contained in the layer in an amount of 70 to 100 mass%, more preferably 85 to 100 mass%.

[Organic electroluminescent device]

The device of the present invention will be described in detail.

The organic electroluminescent device of the present invention is an organic electroluminescent device having a pair of electrodes composed of an anode and a cathode and an organic layer including a light emitting layer between the electrodes, (1) to (3).

In the organic electroluminescent device of the present invention, the light emitting layer is an organic layer, and includes at least one organic layer between the light emitting layer and the cathode, and an organic layer adjacent to the light emitting layer between the light emitting layer and the cathode. .

It is preferable that at least one of the anode and the cathode is transparent or semitransparent in nature of the light-emitting element.

Fig. 1 shows an example of the structure of an organic electroluminescent device according to the present invention. An organic electroluminescent device 10 according to the present invention shown in Fig. 1 has a light emitting layer 6 placed between a cathode 3 and a cathode 9 on a support substrate 2. [ Specifically, a hole injecting layer 4, a hole transporting layer 5, a light emitting layer 6, a hole blocking layer 7 and an electron transporting layer 8 are stacked in this order between the anode 3 and the cathode 9, .

≪ Configuration of organic layer &

The layer structure of the organic layer is not particularly limited and may be appropriately selected depending on the application and purpose of the organic electroluminescent device, but is preferably formed on the transparent electrode or on the back electrode. In this case, an organic layer is formed on the front surface or one surface of the transparent electrode or the back electrode.

The shape, size and thickness of the organic layer are not particularly limited and may be appropriately selected according to the purpose.

Specific examples of the layer configuration include the following, but the present invention is not limited to these configurations.

ㆍ anode / hole transporting layer / light emitting layer / electron transporting layer / cathode,

ㆍ anode / hole transporting layer / light emitting layer / block layer / electron transporting layer / cathode,

ㆍ anode / hole transporting layer / light emitting layer / block layer / electron transporting layer / electron injecting layer / cathode,

ㆍ anode / hole injecting layer / hole transporting layer / light emitting layer / block layer / electron transporting layer / cathode,

ㆍ anode / hole injecting layer / hole transporting layer / light emitting layer / electron transporting layer / electron injecting layer / cathode,

ㆍ anode / hole injecting layer / hole transporting layer / light emitting layer / block layer / electron transporting layer / electron injecting layer / cathode.

The structure of the organic electroluminescent device, the substrate, the cathode and the anode are described in detail in, for example, Japanese Patent Application Laid-Open No. 2008-270736, and the matters described in the publication can be applied to the present invention.

<Substrate>

The substrate used in the present invention is preferably a substrate that does not scatter or attenuate light emitted from the organic layer. In the case of an organic material, it is preferable that it is excellent in heat resistance, dimensional stability, solvent resistance, electrical insulation and workability.

<Anode>

The anode usually has a function as an electrode for supplying holes to the organic layer, and the shape, structure, size and the like of the anode are not particularly limited and can be appropriately selected from known electrode materials according to the purpose and purpose of the light-emitting element. As described above, the anode is usually formed as a transparent anode.

<Cathode>

The shape of the cathode is not particularly limited as long as it has a function as an electrode for injecting electrons into the organic layer. The shape, structure, and size of the cathode are not particularly limited and may be appropriately selected from known electrode materials according to the purpose and purpose of the light-emitting element.

As for the substrate, the positive electrode and the negative electrode, the matters described in paragraphs [0070] to [0089] of Japanese Laid-Open Patent Publication No. 2008-270736 can be applied to the present invention.

<Organic layer>

The organic layer in the present invention will be described.

[Formation of organic layer]

In the organic electroluminescent device of the present invention, each organic layer can be preferably formed by any of a solution coating process such as a dry film formation method such as a vapor deposition method and a sputtering method, a transfer method, a printing method, a spin coat method, and a bar coat method have. It is preferable that at least one of the organic layers is formed by a solution coating process.

[Light Emitting Layer]

The light emitting layer is a layer having a function of receiving holes from the anode, the hole injecting layer or the hole transporting layer, receiving electrons from the cathode, the electron injecting layer or the electron transporting layer, and providing a place for recombination of holes and electrons to emit light when the electric field is applied .

The present invention also relates to a light-emitting layer containing the compound represented by the above general formulas (1) to (3). The light emitting layer of the present invention can be used in an organic electroluminescent device.

The substrate, the anode, the cathode, the organic layer, and the light-emitting layer are described in detail in, for example, Japanese Unexamined Patent Application Publication No. 2008-270736 and Japanese Unexamined Patent Publication No. 2007-266458, have. Further, the light emitting layer may contain a material which does not have charge transportability and does not emit light.

(Luminescent material)

As the light-emitting material in the present invention, a phosphorescent light-emitting material, a fluorescent light-emitting material, and the like can be used.

The light-emitting layer in the present invention may contain two or more kinds of light-emitting materials in order to improve the color purity or to widen the light emission wavelength range. The device of the present invention preferably contains at least one phosphorescent metal complex in addition to the light emitting layer.

It is preferable from the viewpoint of driving durability that the light emitting material in the present invention also satisfies the relation of 1.2 eV> ΔIp> 0.2 eV and / or 1.2 eV> ΔEa> 0.2 eV with respect to the host material. Here,? Ip represents the difference between the Ip values of the host material and the light emitting material, and? Ea represents the difference between the Ea value of the host material and the light emitting material.

At least one of the light emitting materials is preferably a platinum complex material or an iridium complex material.

In the present invention, the luminescent layer preferably contains a platinum complex material or an iridium complex material having a four-position ligand, and more preferably an iridium complex material.

The fluorescent light-emitting material and the phosphorescent light-emitting material are described in detail, for example, in paragraphs [0100] to [0164] of JP-A No. 2008-270736 and paragraphs [0088] to [0090] of JP-A No. 2007-266458 And the matters described in these publications can be applied to the present invention.

The platinum complex is preferably a platinum complex represented by the following formula (C-1).

L ¹ , L ² and L ³ each independently represent a single bond or a divalent linking group.) In the formula, Q ¹ , Q ² , Q ³ and Q ⁴ each independently represent a ligand coordinated to Pt.

The general formula (C-1) will be described. Q ¹ , Q ² , Q ³ and Q ⁴ each independently represent a ligand coordinated to Pt. At this time, the combination of Q ¹ , Q ² , Q ^3, and Q ⁴ with Pt may be covalent bond, ionic bond, coordination bond, or the like. Q ^1, Q ^2, atom bonded to the Q ³ and Q ⁴ of Pt is, a carbon atom, a nitrogen atom, an oxygen atom, a sulfur atom, a phosphorus atom is preferable, and Q ^1, Q ^2, Q ³ and Q ⁴ of the Pt At least one of the bonding atoms is preferably a carbon atom, more preferably two carbon atoms, and particularly preferably two carbon atoms and two nitrogen atoms.

Q ¹ , Q ² , Q ³ and Q ⁴ bonded to Pt by a carbon atom may be an anionic ligand or a neutral ligand. The anionic ligand includes a vinyl ligand, an aromatic hydrocarbon ring ligand (for example, benzene A thiophene ligand, a pyridine ligand, a pyrazine ligand, a pyrimidine ligand, a pyridazine ligand, a triazine ligand, a thiazole ligand, or a thiazole ligand), a heterocyclic ligand , An oxazole ligand, a pyrrole ligand, an imidazole ligand, a pyrazole ligand, a triazole ligand, and an axial ring (for example, a quinoline ligand, a benzothiazole ligand, etc.) containing them. The neutral ligand is a carbenic ligand.

Q ¹ , Q ² , Q ³ and Q ^{4 which} are bonded to Pt by a nitrogen atom may be a neutral ligand or an anion ligand, and examples of the neutral ligand include a nitrogen-containing aromatic heterocyclic ligand (pyridine ligand, pyrazine ligand, (Such as a pyrimidine ligand, a pyridazine ligand, a triazine ligand, an imidazole ligand, a pyrazole ligand, a triazole ligand, an oxazole ligand, a thiazole ligand and an axial foyer containing them (for example, a quinoline ligand, a benzimidazole ligand, )), An amine ligand, a nitrile ligand, and an imine ligand. Examples of the anionic ligand include amino ligands, imino ligands, nitrogen nitrogen aromatic heterocyclic ligands (pyrrole ligands, imidazole ligands, triazole ligands, and axial fibrils including them (for example, indole ligands, benzimidazole ligands, etc.) .

Q ¹ , Q ² , Q ³ and Q ^{4 which} are bonded to Pt by an oxygen atom may be a neutral ligand or an anionic ligand. The neutral ligand may be an ether ligand, a ketone ligand, an ester ligand, an amide ligand, A heterocyclic ligand (a furan ligand, an oxazole ligand, and an axial fullerene such as a benzoxazole ligand). Examples of the anionic ligand include an alkoxy ligand, an aryloxy ligand, a heteroaryloxy ligand, an acyloxy ligand, a silyloxy ligand, and the like.

Q ¹ , Q ² , Q ³ and Q ⁴ bonded to Pt by a sulfur atom may be a neutral or an anionic ligand. The neutral ligand may be a thioether ligand, a thioketone ligand, a thioester ligand, a thioamide A ligand, a sulfo heterocyclic ligand (a thiophene ligand, a thiazole ligand, and an axial fullerene (benzothiazole ligand, etc.) containing them). Examples of the anionic ligand include an alkylmercapto ligand, an arylmercapto ligand, a heteroarylmercapto ligand, and the like.

Q ¹ , Q ² , Q ³ and Q ^{4 which} are bonded to Pt by a phosphorus atom may be a neutral ligand or an anionic ligand. Examples of the neutral ligand include a phosphine ligand, a phosphate ester ligand, a phosphorous ester ligand, A cyclic ligand (a phosphine ligand, etc.), and an anionic ligand includes a phosphino ligand, a phosphinyl ligand, a phosphoryl ligand, and the like.

Q ¹ , Q ² , Q ³ and Q ⁴ may have a substituent. As the substituent, those exemplified as the substituent group A can suitably be used. In addition, substituents may be connected to each other (when Q ³ and Q ⁴ are connected, a Pt complex of a cyclic quadrivalent ligand is formed).

Q ¹ , Q ² , Q ³ and Q ⁴ are preferably an aromatic hydrocarbon ring ligand which is bonded to Pt by a carbon atom, an aromatic heterocyclic ligand which is bonded to Pt by a carbon atom, An alkyloxy ligand, an aryloxy ligand, a heteroaryloxy ligand, or a silyloxy ligand, more preferably an aromatic hydrocarbon ring ligand which binds to the Pt to a carbon atom, a carbon-carbon double bond ligand An aromatic heterocyclic ligand which is bonded to Pt by an atom, a nitrogen-containing aromatic heterocyclic ligand which binds to Pt by a nitrogen atom, an acyloxy ligand, an aryloxy ligand, more preferably an aromatic hydrocarbon A ring ligand, an aromatic hetero ring ligand which binds to Pt by a carbon atom, nitrogen Also binding to Pt by those aromatic heterocyclic nitrogen ligand, an acyloxy ligand.

L ¹ , L ² and L ³ represent a single bond or a divalent linking group. Examples of the divalent connecting group represented by L ¹ , L ² and L ³ include an alkylene group (e.g., methylene, ethylene, propylene), an arylene group (phenylene, naphthalene diyl), a heteroarylene group (e.g., pyridinyl, (-NR _L- ) (phenylimino group, etc.), an oxy group (-O-), a thio group (-S-), a phosphine group (-PR _L- ) (phenylphosphinyl group, etc.) (-SiR _L R _L '-) (dimethylsilylene group, phenylsilylene group, etc.), or a combination thereof. Here, each of R _L and R _L 'independently represents an alkyl group or an aryl group, preferably an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 20 carbon atoms. These linking groups may further have a substituent. L ¹ , L ² and L ³ are preferably a single bond, an alkylene group, an arylene group, a heteroarylene group, an imino group, an oxy group, a thio group, or a silylene group, more preferably from the viewpoints of stability of a complex and light emission quantum yield The alkylene group is preferably a single bond, an alkylene group, an arylene group or an imino group, more preferably a single bond, an alkylene group or an arylene group, more preferably a single bond, a methylene group or a phenylene group, , A di-substituted methylene group, and still more preferably a single bond, a dimethylmethylene group, a diethylmethylene group, a diisobutylmethylene group, a dibenzylmethylene group, an ethylmethylmethylene group, a methylpropylmethylene group, , A diphenylmethylene group, a methylphenylmethylene group, a cyclohexanediyl group, a cyclopentanediyl group, a fluorenediyl group, and a fluoromethylmethylene group.

L ¹ is particularly preferably a dimethylmethylene group, a diphenylmethylene group or a cyclohexanediyl group, and most preferably a dimethylmethylene group.

L ² and L ³ are most preferably a single bond.

Among the platinum complexes represented by the general formula (C-1), platinum complexes represented by the following general formula (C-2) are more preferable.

(Wherein, L ²¹ represents a single bond or a divalent linking group. A ^21, A ²² each independently represents a carbon atom or a nitrogen atom. Z ^21, Z ²² represents a nitrogen-containing aromatic hetero ring, each independently. Z ²³ and Z ²⁴ each independently represent a benzene ring or an aromatic heterocyclic ring.

The general formula (C-2) will be described. L ²¹ has the same meaning as L ¹ in the general formula (C-1), and the preferable range thereof is also the same.

A ²¹ and A ²² each independently represent a carbon atom or a nitrogen atom. At least one of A ²¹ and A ²² is preferably a carbon atom, and both A ²¹ and A ²² are carbon atoms from the viewpoints of the stability of the complex and the yield of light emission of the complex.

* Z ²¹ and Z ²² each independently represent a nitrogen-containing aromatic heterocyclic ring. Examples of the nitrogen-containing heteroaromatic ring represented by Z ²¹ and Z ²² include a pyridine ring, a pyrimidine ring, a pyrazine ring, a triazine ring, an imidazole ring, a pyrazole ring, an oxazole ring, a thiazole ring, A thiadiazole ring, and the like. The ring represented by Z ²¹ and Z ²² is preferably a pyridine ring, a pyrazine ring, an imidazole ring, or a pyrazole ring in view of the stability of the complex, the control of the emission wavelength, and the quantum yield of light emission. More preferably, A pyridine ring, a pyrazole ring, and more preferably a pyridine ring.

The nitrogen-containing aromatic heterocyclic ring represented by Z ²¹ and Z ²² may have a substituent. As the substituent on the carbon atom, the substituent group B can be applied as the substituent on the nitrogen atom. The substituent on the carbon atom is preferably an alkyl group, a polyfluoroalkyl group, an aryl group, an aromatic heterocyclic group, a dialkylamino group, a diarylamino group, an alkoxy group, a cyano group or a halogen atom. The substituent is suitably selected for control of the emission wavelength or the electric potential. In the case of shortening the wavelength, the electron donating group, the fluorine atom and the aromatic ring group are preferable. Examples thereof include an alkyl group, a dialkylamino group, an alkoxy group, a fluorine atom, A heterocyclic group and the like are selected. In addition, in the case of long wavelength conversion, electron donating groups are preferable, and for example, cyano group, polyfluoroalkyl group and the like are selected. The substituent on the nitrogen atom is preferably an alkyl group, an aryl group or an aromatic heterocyclic group, and from the viewpoint of stability of the complex, an alkyl group or an aryl group is preferable. The substituents may be connected to each other to form a condensed ring. Examples of the ring formed include a benzene ring, a pyridine ring, a pyrazine ring, a pyridazine ring, a pyrimidine ring, an imidazole ring, an oxazole ring, a thiazole ring, A thiophene ring, a furan ring, and the like.

Z ²³ and Z ²⁴ each independently represent a benzene ring or an aromatic heterocyclic ring. The nitrogen-containing aromatic heterocyclic ring represented by Z ²³ and Z ²⁴ includes a pyridine ring, a pyrimidine ring, a pyrazine ring, a pyridazine ring, a triazine ring, an imidazole ring, a pyrazole ring, an oxazole ring, a thiazole ring, A ring, an oxadiazole ring, a thiadiazole ring, a thiophene ring, a furan ring, and the like. The ring represented by Z ²³ and Z ²⁴ is preferably a benzene ring, a pyridine ring, a pyrazine ring, an imidazole ring, a pyrazole ring, or a thiophene ring in view of stability of a complex, control of an emission wavelength, A benzene ring, a pyridine ring and a pyrazole ring, more preferably a benzene ring and a pyridine ring.

The benzene ring and nitrogen-nitrogen-containing aromatic heterocyclic ring represented by Z ²³ and Z ²⁴ may have a substituent. As the substituent on the carbon atom, the substituent group B may be applied as the substituent on the nitrogen atom. The substituent on the carbon atom is preferably an alkyl group, a polyfluoroalkyl group, an aryl group, an aromatic heterocyclic group, a dialkylamino group, a diarylamino group, an alkoxy group, a cyano group or a halogen atom. The substituent is suitably selected for control of the emission wavelength or the electric potential, but when it is long wavelength, the electron donating group and the aromatic ring group are preferable. For example, an alkyl group, a dialkylamino group, an alkoxy group, an aryl group, an aromatic heterocyclic group, do. In the case of shortening the wavelength, an electron-attracting group is preferable, and for example, a fluorine group, a cyano group, a polyfluoroalkyl group and the like are selected. The substituent on the nitrogen atom is preferably an alkyl group, an aryl group or an aromatic heterocyclic group, and from the viewpoint of stability of the complex, an alkyl group or an aryl group is preferable. The substituents may be connected to form a condensed ring. The ring formed may be a benzene ring, a pyridine ring, a pyrazine ring, a pyridazine ring, a pyrimidine ring, an imidazole ring, an oxazole ring, a thiazole ring, , Thiophene ring, furan ring and the like.

Among the platinum complexes represented by the general formula (C-2), one of the more preferred embodiments is a platinum complex represented by the following general formula (C-4).

(In the formula (C-4), A ⁴⁰¹ to A ⁴¹⁴ each independently represent a CR or a nitrogen atom, R represents a hydrogen atom or a substituent, and L ⁴¹ represents a single bond or a divalent linking group.

* Formula (C-4) will be described.

A ⁴⁰¹ to A ⁴¹⁴ each independently represent a CR or a nitrogen atom. R represents a hydrogen atom or a substituent.

As the substituent represented by R, those exemplified as the substituent group A can be applied.

A ⁴⁰¹ to A ⁴⁰⁶ are preferably CR, and Rs may be connected to each other to form a ring. When A ⁴⁰¹ to A ⁴⁰⁶ are CR, R of A ⁴⁰² and A ⁴⁰⁵ is preferably a hydrogen atom, an alkyl group, an aryl group, an amino group, an alkoxy group, an aryloxy group, a fluorine group or a cyano group, A hydrogen atom, an amino group, an alkoxy group, an aryloxy group and a fluorine group, particularly preferably a hydrogen atom or a fluorine group. The R of A ⁴⁰¹ , A ⁴⁰³ , A ⁴⁰⁴ and A ⁴⁰⁶ is preferably a hydrogen atom, an alkyl group, an aryl group, an amino group, an alkoxy group, an aryloxy group, a fluorine group or a cyano group, more preferably a hydrogen atom, An alkoxy group, an aryloxy group, a fluorine group, and particularly preferably a hydrogen atom.

L ⁴¹ has the same meaning as L ¹ in the general formula (C-1), and the preferable range thereof is also the same.

In A ⁴⁰⁷ to A ⁴¹⁴ , the number of N (nitrogen atom) is preferably 0 to 2, and more preferably 0 to 1, in each of A ⁴⁰⁷ to A ⁴¹⁰ and A ⁴¹¹ to A ⁴¹⁴ . When shifting the emission wavelength of the short wavelength side, A ⁴⁰⁸ and A ⁴¹² of which is preferably a nitrogen atom, the A ⁴⁰⁸ and A ⁴¹² are both more preferably a nitrogen atom.

When A ⁴⁰⁷ to A ⁴¹⁴ represent CR, R of A ⁴⁰⁸ and A ⁴¹² is preferably a hydrogen atom, an alkyl group, a polyfluoroalkyl group, an aryl group, an amino group, an alkoxy group, an aryloxy group, a fluorine group, More preferably a hydrogen atom, a polyfluoroalkyl group, an alkyl group, an aryl group, a fluorine group or a cyano group, and particularly preferably a hydrogen atom, a phenyl group, a polyfluoroalkyl group or a cyano group. The R in A ⁴⁰⁷ , A ⁴⁰⁹ , A ⁴¹¹ and A ⁴¹³ is preferably a hydrogen atom, an alkyl group, a polyfluoroalkyl group, an aryl group, an amino group, an alkoxy group, an aryloxy group, a fluorine group or a cyano group, A hydrogen atom, a polyfluoroalkyl group, a fluorine group or a cyano group, and particularly preferably a hydrogen atom, a phenyl group or a fluorine group. A ⁴¹⁰ and A ⁴¹⁴ are preferably a hydrogen atom or a fluorine group, and more preferably a hydrogen atom. When any of A ⁴⁰⁷ to A ⁴⁰⁹ and A ⁴¹¹ to A ⁴¹³ represents CR, the Rs may be connected to each other to form a ring.

Among the platinum complexes represented by the general formula (C-2), one more preferred embodiment is a platinum complex represented by the following general formula (C-5).

(In the general formula (C-5), each of A ⁵⁰¹ to A ⁵¹² independently represents a CR or a nitrogen atom, R represents a hydrogen atom or a substituent, and L ⁵¹ represents a single bond or a divalent linking group.

The general formula (C-5) will be described. A ⁵⁰¹ to A ⁵⁰⁶ and L ⁵¹ have the same meanings as A ⁴⁰¹ to A ⁴⁰⁶ and L ⁴¹ in the general formula (C-4), and preferable ranges thereof are also the same.

A ⁵⁰⁷ , A ⁵⁰⁸ and A ⁵⁰⁹ and A ⁵¹⁰ , A ⁵¹¹ and A ⁵¹² each independently represent a CR or nitrogen atom. R represents a hydrogen atom or a substituent. As the substituent represented by R, those exemplified as the substituent group A can be applied. When A ⁵⁰⁷ , A ⁵⁰⁸ and A ⁵⁰⁹ and A ⁵¹⁰ , A ⁵¹¹ and A ⁵¹² are CR, R is preferably a hydrogen atom, an alkyl group, a polyfluoroalkyl group, an aryl group, an aromatic heterocyclic group, a dialkylamino group, More preferably a hydrogen atom, an alkyl group, a polyfluoroalkyl group, an aryl group, a dialkylamino group, a cyano group, a fluorine atom, more preferably a hydrogen atom, an alkyl group , A trifluoromethyl group, and a fluorine atom. When possible, substituents may be connected to each other to form a condensed ring structure. At least one of A ⁵⁰⁷ , A ⁵⁰⁸ and A ⁵⁰⁹ and A ⁵¹⁰ , A ⁵¹¹ and A ⁵¹² is preferably a nitrogen atom, more preferably A ⁵¹⁰ or A ⁵⁰⁷ is a nitrogen atom.

Among other platinum complexes represented by the general formula (C-1), another preferred embodiment is a platinum complex represented by the following general formula (C-6).

(Wherein, L ⁶¹ represents a single denotes a bond or a divalent connecting group. A ⁶¹ each independently represents a carbon atom or a nitrogen atom. Z ^61, Z ⁶² represents a nitrogen-containing aromatic hetero ring, each independently. Z ⁶³ is Each independently represent a benzene ring or an aromatic heterocyclic ring Y is an anionic non-ligand ligand which binds to Pt)

The general formula (C-6) will be described. L ⁶¹ has the same meaning as L ¹ in the general formula (C-1), and the preferable range thereof is also the same.

A ⁶¹ represents a carbon atom or a nitrogen atom. From the viewpoints of the stability of the complex and the quantum yield of light emission of the complex, A ⁶¹ is preferably a carbon atom.

Z ⁶¹ and Z ⁶² have the same meanings as Z ²¹ and Z ^{22 in} the general formula (C-2), respectively, and their preferred ranges are also the same. Z ⁶³ has the same meaning as Z ²³ in the formula (C-2), and the same preferable range.

Y is an anionic acyclic ligand which binds to Pt. The ligand type ligand means that the atoms bonded to Pt do not form a ring in the ligand state. The atom to which Pt in Y is bonded is preferably a carbon atom, a nitrogen atom, an oxygen atom or a sulfur atom, more preferably a nitrogen atom or an oxygen atom, and most preferably an oxygen atom.

Y which is bonded to Pt by a carbon atom is a vinyl ligand. Examples of Y bonded to Pt by a nitrogen atom include amino ligands and imino ligands. Examples of Y bonded to Pt by an oxygen atom include an alkoxy ligand, an aryloxy ligand, a heteroaryloxy ligand, an acyloxy ligand, a silyloxy ligand, a carboxyl ligand, a phosphoric acid ligand, and a sulfonic acid ligand. Examples of Y bonded to Pt by a sulfur atom include an alkyl mercapto ligand, an aryl mercapto ligand, a heteroaryl mercapto ligand, and a thiocarboxylic acid ligand.

The ligand represented by Y may have a substituent. As the substituent, those exemplified as the above substituent group A can be appropriately applied. The substituents may be connected to each other.

The ligand represented by Y is preferably a ligand which is bonded to Pt by an oxygen atom, and more preferably an acyloxy ligand, an alkyloxy ligand, an aryloxy ligand, a heteroaryloxy ligand, or a silyloxy ligand, more preferably an acyloxy ligand It is an oxy ligand.

Among the platinum complexes represented by the general formula (C-6), one of the more preferred embodiments is a platinum complex represented by the following general formula (C-7).

*

(Wherein A ⁷⁰¹ to A ⁷¹⁰ each independently represent a CR or nitrogen atom, R represents a hydrogen atom or a substituent, L ⁷¹ represents a single bond or a divalent linking group, Y represents an anionic It is a nonrecordable ligand.)

The general formula (C-7) will be described. L ⁷¹ has the same meaning as L ⁶¹ in formula (C-6) above, and the same preferable range. A ⁷⁰¹ to A ⁷¹⁰ have the same meanings as A ⁴⁰¹ to A ^{410 in the} formula (C-4), and their preferable ranges are also the same. Y has the same meaning as Y in formula (C-6), and the same preferable range.

Specific examples of the platinum complex represented by the general formula (C-1) include compounds described in JP-A No. 2005-310733 [0143] to [0152], [0157] to [0158], [0162] , Compounds described in [0065] to [0083] of JP-A No. 2006-256999, compounds described in JP-A No. 2006-93542 [0065] to [0090], JP-A No. 2007-73891 Compounds described in JP-A No. 2007-324309 [0079] to [0083], compounds described in JP-A No. 2006-93542 [0065] to [0090], compounds disclosed in JP- Compounds described in [0055] to [0071] of JP-A-2007-96255, and compounds [0043] to [0046] of JP-A No. 2006-313796. Other examples include platinum complexes exemplified below.

The platinum complex compound represented by the general formula (C-1) can be synthesized by a method described in, for example, Journal of Organic Chemistry 53, 786, (1988), GRNewkome et al., Page 789, Page 2790, pages 269 to 2790, method described in left column 18 to 38, page 790, method described in right column 19 to column 30 and combinations thereof, Chemische Berichte 113, 2749 (1980), H.Lexy et al. 35, which is incorporated herein by reference.

For example, the ligand or its dissociation product and a metal compound are dissolved in a solvent (for example, a halogen-based solvent, an alcohol-based solvent, an ether-based solvent, an ester-based solvent, a ketone-based solvent, a nitrile- (Various organic and inorganic bases such as sodium methoxide, t-butoxypotassium, t-butoxyphenylacetate, etc.) in the presence or absence of a solvent in the presence of a base Triethylamine, potassium carbonate, etc.) or in the presence of a base, at room temperature or below, or by heating (microwave heating in addition to normal heating is also effective).

The content of the compound represented by the general formula (C-1) in the light emitting layer of the present invention is preferably 1 to 30 mass%, more preferably 3 to 25 mass%, and more preferably 5 to 20 mass% More preferable.

The iridium complex is preferably an iridium complex represented by the following formula (T-1).

[Compound represented by the formula (T-1)]

The compound represented by the general formula (T-1) is explained.

Wherein R _T3 ', R _T3 , R _T4 , R _T5 and R _T6 each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, an alkynyl group, -CN, a perfluoroalkyl group , A trifluorovinyl group, -CO ₂ R _T , -C (O) R _T , -N (R _T ) ₂ , -NO ₂ , -OR _T , a halogen atom, an aryl group or a heteroaryl group, And may have a substituent Z.

Q is a 5- or 6-membered aromatic heterocyclic ring or condensed aromatic heterocyclic ring containing one or more nitrogen atoms.

R _T3 , R _T4 , R _T5 and R _T6 may be bonded to each other to form a condensed 4- to 7-membered ring, and the condensed 4- to 7-membered ring may be a cycloalkyl, aryl or heteroaryl, The condensed 4- to 7-membered ring may further have a substituent Z.

R _T3 'and _T6 R is _{-C (R T) 2 -C (} R T) 2 -, -CR T = CR T -, -C (R T) 2 -, -O-, -NR T -, - May be linked by a linking group selected from OC (R _T ) ₂ -, -NR _T -C (R _T ) ₂ - and -N = CR _T - to form a ring.

R _T each independently represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, a heteroalkyl group, an aryl group or a heteroaryl group, and may further have a substituent Z.

Z is a halogen atom, each independently, -R ', -OR', -N (R ') 2, -SR', -C (O) R ', -C (O) OR', -C (O) N _{(R ') 2, -CN,} -NO 2, -SO 2, -SOR', -SO ₂ R represents a 'or -SO ₃ R', R 'are each independently a hydrogen atom, an alkyl, perhaloalkyl, An alkenyl group, an alkynyl group, a heteroalkyl group, an aryl group or a heteroaryl group.

(XY) represents a subsidiary ligand. m _T represents an integer of 1 to 3, and n _T represents an integer of 0 to 2. m _T + n _T is 3.)

The compound represented by the general formula (T-1) is a complex having iridium (Ir) as a metal, and when combined with the charge-transporting material of the present invention, the transport of charges in the light-emitting layer can be made more smooth and luminous efficiency can be increased.

The alkyl group may have a substituent, may be saturated or unsaturated, and the group which may be substituted includes the substituent Z described above. The alkyl group represented by R ₃ ', R ₃ , R ₄ , R ₅ and R ₆ is preferably an alkyl group having 1 to 8 total carbon atoms, more preferably an alkyl group having 1 to 6 total carbon atoms, For example, methyl group, ethyl group, i-propyl group, t-butyl group and the like.

The cycloalkyl group may have a substituent, may be saturated or unsaturated, and the group which may be substituted includes the substituent Z described above. The cycloalkyl group represented by R ₃ ', R ₃ , R ₄ , R ₅ and R ₆ is preferably a cycloalkyl group having 4 to 7 ring atoms, more preferably a cycloalkyl group having 5 to 6 total carbon atoms, For example, a cyclopentyl group, a cyclohexyl group and the like.

The alkenyl group represented by R _T3 ', R _T3 , R _T4 , R _T5 and R _T6 is preferably an alkenyl group having 2 to 30 carbon atoms, more preferably 2 to 20 carbon atoms, particularly preferably 2 to 10 carbon atoms, For example, vinyl, allyl, 1-propenyl, 1-isopropenyl, 1-butenyl, 2-butenyl, 3-pentenyl and the like.

The alkynyl group represented by R _T3 ', R _T3 , R _T4 , R _T5 and R _T6 preferably has 2 to 30 carbon atoms, more preferably 2 to 20 carbon atoms, particularly preferably 2 to 10 carbon atoms, For example, ethynyl, propargyl, 1-propynyl, 3-pentynyl and the like.

The perfluoroalkyl group represented by R ₃ ', R ₃ , R ₄ , R ₅ , and R ₆ includes those in which the hydrogen atoms of all the aforementioned alkyl groups are substituted with fluorine atoms.

The halogen atom represented by R ₃ ', R ₃ , R ₄ , R ₅ and R ₆ is preferably a fluorine atom.

The aryl group represented by R _T3 ', R _T3 , R _T4 , R _T5 and R _T6 is preferably a substituted or unsubstituted aryl group having 6 to 30 carbon atoms such as a phenyl group, a tolyl group and a naphthyl group have.

The heteroaryl group represented by R _T3 ', R _T3 , R _T4 , R _T5 and R _T6 is preferably a heteroaryl group having 5 to 8 carbon atoms, more preferably a substituted or unsubstituted heteroaryl group having 5 or 6 atoms And examples thereof include a pyridyl group, a pyrazinyl group, a pyridazinyl group, a pyrimidinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a quinazolinyl group, a cinnolinyl group, a phthalazinyl group, A thiazolyl group, an imidazolyl group, a benzimidazolyl group, a triazolyl group, an oxazolyl group, a benzoxazolyl group, an imidazolyl group, an imidazolyl group, an imidazolyl group, A thiazolyl group, a benzothiazolyl group, a pyrrolidinyl group, a piperidinyl group, a piperazinyl group, a benzothiazolyl group, an isothiazolyl group, a benzisothiazolyl group, a thiadiazolyl group, Imidazolidinyl group, thiazolinyl group, sulforanyl group, carbazolyl group, dibenzo Group, a dibenzo-thienyl group, and the like based degrees turned 7 flutes. Preferable examples are a pyridyl group, a pyrimidinyl group, an imidazolyl group, and a thienyl group, and more preferably a pyridyl group and a pyrimidinyl group.

And R _T3 ', R _T3, R _T4, R _T5 and R _T6 preferably a hydrogen atom, an alkyl group, a cyano group, a perfluoroalkyl group, a dialkylamino group, a fluorine atom, an aryl group, a heteroaryl group or a halogen atom as a, More preferably a hydrogen atom, an alkyl group, an aryl group or a halogen atom, more preferably a hydrogen atom, an alkyl group, a cyano group, a trifluoromethyl group, a fluorine atom, an aryl group or a halogen atom, A methyl group, an isobutyl group, a phenyl group or a fluorine atom. The substituent Z is preferably an alkyl group, an alkoxy group, a fluorine atom, a cyano group or a dialkylamino group, and more preferably a hydrogen atom.

R _T3 , R _T4 , R _T5 and R _T6 may be bonded to each other to form a condensed 4- to 7-membered ring, and the condensed 4- to 7-membered ring may be a cycloalkyl, aryl or heteroaryl, The condensed 4- to 7-membered ring may further have a substituent Z. The definitions and preferable ranges of the cycloalkyl, aryl and heteroaryl to be formed are the same as those of the cycloalkyl group, aryl group and heteroaryl group defined by R _T3 ', R _T3 , R' _T4 , R _T5 and R _T6 .

Examples of the aromatic heterocyclic rings represented by ring Q include pyridine rings, pyrazine rings, pyrimidine rings, pyrazole rings, imidazole rings, triazole rings, oxazole rings, oxadiazole rings, thiazole rings, thiadiazole rings, . Is preferably a pyridine ring or a pyrazine ring, more preferably a pyridine ring.

The condensed aromatic heterocyclic ring represented by ring Q includes a quinoline ring, an isoquinoline ring, and a quinoxaline ring. Preferably a quinoline ring, an isoquinoline ring, and more preferably a quinoline ring.

m _T is preferably 1 to 3, more preferably 2 or 3. That is, n _T is preferably 0 or 1. The kind of the ligand in the complex is preferably one or two kinds, more preferably one kind. When a reactive group is introduced into the complex molecule, it is also preferable that the ligand is composed of two kinds from the viewpoint of ease of synthesis.

The metal complex represented by the general formula (T-1) may be composed of a main ligand or a tautomer thereof and a ligand different from the main ligand or a tautomer thereof, or the ligand of the metal complex may be represented by a main ligand or a tautomer thereof Or may be composed of only partial structures.

Further, a ligand (also referred to as a coordination compound) known to the person skilled in the art as a so-called ligand, which is used for forming a conventionally known metal complex, may be provided as a sub-ligand which does not contribute to light emission as required.

There are various well-known ligands to be used in conventionally known metal complexes. For example, &quot; Photochemistry and Photophysics of Coordination Compounds &quot; by H. Yersin, Springer-Verlag Co., (For example, a halogen ligand (preferably a chlorine ligand), a nitrogen nitrogen heteroaryl ligand (for example, bipyridyl, phenanthroline, etc.) described in Shokabosa, Yamamoto Akio, ), A diketone ligand (e.g., acetylacetone, etc.). As a side ligand, a diketone or a picolinic acid derivative is preferable.

Examples of the sub-ligands will be specifically described below, but the present invention is not limited thereto.

In the example of the sub-ligand, * represents the coordination position with respect to iridium in the general formula (T-1). Rx, Ry and Rz each independently represent a hydrogen atom or a substituent. Examples of the substituent include a substituent selected from the above-mentioned substituent group A. Preferably, each of Rx and Rz is independently an alkyl group, a perfluoroalkyl group, a halogen atom or an aryl group, more preferably an alkyl group having 1 to 4 carbon atoms, a perfluoroalkyl group having 1 to 4 carbon atoms, a fluorine atom, A phenyl group which may be substituted, and most preferably a methyl group, an ethyl group, a trifluoromethyl group, a fluorine atom and a phenyl group. Ry is preferably a hydrogen atom, an alkyl group, a perfluoroalkyl group, a halogen atom or an aryl group, more preferably a hydrogen atom, an alkyl group having 1 to 4 carbon atoms or a phenyl group which may be substituted, An atom, or a methyl group. Rx, Ry, and Rz are chemically stable substituents, and do not affect the effect of the present invention, since these sub-ligands are considered to be not the sites where electrons are transported or carried by the charge in the device.

(I-1), (I-4) or (I-5), and most preferably (I-1), because the complex synthesis method is generally known and easy.

In the present invention, it is most preferable that the sub-ligand is acetylacetonate (acac) in view of stability of the complex and high luminescence efficiency. * Represents the coordination position with respect to iridium in the general formula (T-1).

The complex having these side ligands can be synthesized in the same manner as in known synthesis examples by using corresponding ligand precursors. For example, it can be synthesized by the following method using commercially available difluoroacetylacetone in the same manner as in the method described on page 46 of International Publication No. 2009-073245.

As the ligand, a monoanionic bidentate ligand having a phenylpyridine skeleton can be further used. Specifically, a monoanionic bidentate ligand represented by the general formula (I-15) can be exemplified.

R _T7 'and R _T7 to R _T10 in the general formula (I-15) have the same meanings as those of R _T3 ' and R _T3 to R _T6 in the general formula (T-1), and preferable ones are also the same. R _T8 'to R ₁₀ ' have the same meaning as R _T3 '.

R _T8 'is preferably a hydrogen atom, an alkyl group, an aryl group or a fluorine atom, more preferably a hydrogen atom.

R _T9 'and R _10' are preferably combined represent a hydrogen atom, or together to form a condensed 4-7 atom groups cyclic, and the condensation of 4 to 7 atom cyclic group is a cycloalkyl group, a cycloalkyl heterocycloalkyl group, an aryl group Or a heteroaryl group, and more preferably an aryl group.

R _T9 'to R _T10 ' may further have a substituent Z, and the substituent Z is preferably an alkyl group, an alkoxy group, a fluorine atom, a cyano group, an alkylamino group or a diarylamino group, more preferably an alkyl group.

The compound represented by the above general formula (T-1) is preferably a compound represented by the following general formula (T-2).

Wherein R _T3 'to R _T6 ' and R _T3 to R _T6 each independently represent a hydrogen atom, vinyl group _{fluoro, -CO 2 R T, -C (} O) R T, -N (R T) 2, -NO 2, -OR T, a halogen atom, an aryl group or a heteroaryl group, a substituent in more Z .

R _T3 , R _T4 , R _T5 and R _T6 may be bonded to each other to form a condensed 4- to 7-membered ring, and the condensed 4- to 7-membered ring may further have a substituent Z.

R _T3 'and _T6 R is _{-C (R T) 2 -C (} R T) 2 -, -CR T = CR T -, -C (R T) 2 -, -O-, -NR T -, - May be linked by a linking group selected from OC (R _T ) ₂ -, -NR _T -C (R _T ) ₂ - and -N = CR _T - to form a ring.

R _T each independently represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, a heteroalkyl group, an aryl group or a heteroaryl group, and may further have a substituent Z.

Z is a halogen atom, each independently, -R ', -OR', -N (R ') 2, -SR', -C (O) R ', -C (O) OR', -C (O) N _{(R ') 2, -CN,} -NO 2, -SO 2, -SOR', -SO ₂ R represents a 'or -SO ₃ R', R 'are each independently a hydrogen atom, an alkyl, perhaloalkyl, An alkenyl group, an alkynyl group, a heteroalkyl group, an aryl group or a heteroaryl group.

(XY) represents a subsidiary ligand. m _T represents an integer of 1 to 3, and n _T represents an integer of 0 to 2. m _T + n _T is 3.)

The preferable range of R _T3 ', R _T3 to R _T6 , (XY), m _T and n _{T in} the general formula (T-2) is preferably R _T3 ', R _T3 ~ R _T6 , (XY), m _T and n _T.

R _T4 'is preferably a hydrogen atom, an alkyl group, an aryl group or a fluorine atom, more preferably a hydrogen atom.

R _T5 'and R _T6' is preferably in combination represent a hydrogen atom, or together to form a condensed 4-7 atom groups cyclic, and the condensation of 4 to 7 atom cyclic group is a cycloalkyl group, a cycloalkyl heterocycloalkyl group, an aryl group Or a heteroaryl group, and more preferably an aryl group.

R _T4 'to R _T6 ' may further have a substituent Z, and the substituent Z is preferably an alkyl group, an alkoxy group, a fluorine atom, a cyano group, an alkylamino group or a diarylamino group, more preferably an alkyl group.

One preferred form of the compound represented by the above general formula (T-2) is a compound represented by the following general formula (T-3).

In the general formula (T-3), R _T3 ', R _T4 ', R _T5 ', R _T6 ', R _T3 , R _T4 , R _T5 and R _{T6 each} represent a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, , -CN, a perfluoroalkyl group, -N (R _T ) ₂ , a halogen atom, an aryl group or a heteroaryl group, and may further have a substituent Z. R _T and R _T are as defined in the aforementioned general formula (T-1).

R _T3 ', R _T4 ', R _T5 ', R _T6 ', R _T3 , R _T4 , R _T5 and R _T6 are bonded to each other to form a condensed ring.

Z each independently represents a halogen atom, -R ', -OR', -N (R ') ₂ , -SR' or -CN and R 'independently represents a hydrogen atom, an alkyl group, a perhaloalkyl group, , An alkynyl group, a heteroalkyl group, an aryl group or a heteroaryl group.

(XY), and m _T n _T is a (XY), as defined, and m _T n _T in the formula (T-2), preferable ones are also the same.

* The compound represented by the above general formula (T-3) is preferably a compound represented by the following general formula (T-3-1).

R _T3 '~ R _T6' in formula _{(T-3-1), R T3} ~ R T6 and _T m is, R _T3 '~ R _T6' in the formula _(T3), R T3 To R _T6 and m _T, and preferred ones are also the same.

R _T7 to R _T10 have the same meanings as R _T3 to R _T6 . R _T7 'to R _T10 ' have the same meanings as R _T3 'to R _T6 '.

Another preferred form of the compound represented by the general formula (T-2) is a compound represented by the following general formula (T-4).

R _T3 '~ R _T6' in formula _{(T-4), R T3} ~ R T6, (XY), m T and n _T is ~ R _T3 'in formula (T-2) R _T6 ', R _T3 to R _T6 , (XY), m _T and n _T , and preferred ones are also the same. R _T7 'has the same meaning as R _T3 ', and preferred ones are also the same.

Another preferred form of the compound represented by the general formula (T-2) is a compound represented by the following general formula (T-5).

R _T3 '~ R _T7' in formula _{(T-5), R T3} ~ R T6, (XY), m T and n _T is ~ R _T3 'in formula (T-2) R _T6 ', R _T3 to R _T6 , (XY), m _T and n _T , and preferred ones are also the same.

Specific examples of the compound represented by the formula (T-1) are listed below, but are not limited thereto.

The compound exemplified as the compound represented by the general formula (T-1) can be synthesized by various methods described in JP-A-2009-99783 and US Pat. No. 7279232. [ After the synthesis, it is preferable to carry out purification by column chromatography, recrystallization and the like, and then purify by sublimation purification. Not only the organic impurities can be separated by the sublimation purification, but also inorganic salts and residual solvents can be effectively removed. In the Ir complex, a structural isomer such as a facial or meridioid exists depending on the orientation direction of the ligand. However, any of the structural isomers may be used as a light emitting material, or a mixture of several structural isomers may be used.

Another preferred embodiment of the iridium complex is an iridium complex comprising a bidentate ligand represented by the following general formula (A1-5).

(In the general formula (A1-5), R _1a to R _1i each independently represent a hydrogen atom or a substituent.)

R _1a ~ R _1i is preferably a hydrogen atom, a hydrocarbon group (preferably an alkyl group, a cycloalkyl group or an aryl group), a cyano group, a fluorine _{atom, OR 2a, SR 2a, NR} 2a, R 2b, BR 2a R 2b or SiR _2a R _2b R _2c . R _2a to R _2c each independently represents a hydrocarbon group or a hydrocarbon group substituted with a hetero atom, and R _1a to R _1i , R _2a to R _2c May be bonded to each other to form a saturated or unsaturated aromatic ring or non-aromatic ring. If it is bonded to the nitrogen atom, R _1a ~ R _1i is not present.

It is preferable that at least one of R _1a to R _1i is an aryl group having a dihedral angle of 70 degrees or more with respect to the parent skeleton, more preferably a substituent represented by the following general formula ss-1, and 2,6- , And it is most preferable that R _1b is a 2,6-disubstituted aryl group.

(In the general formula ss-1, each of Ra, Rb and Rc independently represents a hydrogen atom, an alkyl group or an aryl group, and the number of Rc is 0 to 3.)

The alkyl group represented by Ra, Rb and Rc preferably has 1 to 30 carbon atoms, more preferably 1 to 20 carbon atoms, and particularly preferably 1 to 10 carbon atoms, such as methyl, ethyl, n-propyl, iso Propyl, n-butyl, tert-butyl, n-octyl, n-nonyl, n-decyl, n-dodecyl, n-octadecyl, n-hexadecyl, cyclopropyl, cyclobutyl, cyclopentyl, Cyclooctyl, 1-adamantyl, trifluoromethyl and the like, and a methyl group or an isopropyl group is preferable.

The aryl group represented by Ra, Rb and Rc preferably has 6 to 30 carbon atoms, more preferably 6 to 20 carbon atoms, and particularly preferably 6 to 12 carbon atoms, such as phenyl, o-methylphenyl, m- , p-methylphenyl, 2,6-xylyl, p-cumenyl, mesityl, naphthyl, anthranyl and the like are exemplified, and a phenyl group, 2,6-xylyl and mesityl are preferable, Do.

At least one of Ra and Rb is preferably selected from an alkyl group or an aryl group, more preferably at least one of Ra and Rb is selected from an alkyl group, more preferably Ra and Rb are all alkyl groups, Most preferably Rb is a methyl group or an isopropyl group.

As the 2,6-disubstituted aryl group, 2,6-dimethylphenyl group, 2,4,6-trimethylphenyl group, 2,6-diisopropylphenyl group, 2,4,6-triisopropylphenyl group, Dimethylphenyl group, 2,6-dimethylphenyl group, 2,6-dimethylphenyl group, 2,6-dimethylphenyl group, 2,6- (4-isopropylphenyl) phenyl group, 2,6-diisopropyl-4- (3,5-dimethylphenyl) phenyl group (2,6-diisopropyl-4- (pyridin-4-yl) phenyl group or 2,6-di- (3,5-dimethylphenyl) phenyl group.

The number of Rc is preferably 0 or 1. The plurality of Rc may be the same or different.

It is preferable that at least one of R _1a to R _1i is an alkyl group. More preferably, R _1e is an alkyl group. The alkyl group is preferably an alkyl group branched at a position apart from the benzyl position having 4 or more carbon atoms, more preferably a methyl group or neopentyl group, and more preferably a neopentyl group.

At least one of R _1a and R _1b is preferably an electron donating group, and R _1a is preferably an electron donating substituent, more preferably R _1a is a methyl group.

The hydrocarbon group is a monovalent or divalent, chain-like, branched or cyclic substituent, and is composed of only carbon atoms and hydrogen atoms.

Examples of the monovalent hydrocarbon group include an alkyl group having 1 to 20 carbon atoms; An alkyl group having 1 to 20 carbon atoms substituted with at least one group selected from an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 8 carbon atoms, and an aryl group; A cycloalkyl group having 3 to 8 carbon atoms; A cycloalkyl group having 3 to 8 carbon atoms substituted with at least one group selected from an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 8 carbon atoms, and an aryl group; An aryl group having 6 to 18 carbon atoms; An alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 8 carbon atoms, and an aryl group substituted with at least one group selected from an aryl group.

Examples of the divalent hydrocarbon group include -CH ₂ -, -CH ₂ CH ₂ -, -CH ₂ CH ₂ CH ₂ -, and 1,2-phenylene group.

In order to suppress the steric hindrance due to the substituent and maintain the chemical stability of the ligand, it is preferable that R _1c , R _1f and R _1i represent a hydrogen atom.

The bidentate ligand represented by the general formula (A1-5) is preferably a bidentate ligand represented by the following general formula (A1-6).

(In the general formula (A1-6), R _1a represents a hydrogen atom or a substituent, R b and R c each independently represent a hydrogen atom, an alkyl group or an aryl group.)

In the general formula (A1-6), the preferred R _1a is the same as R _1a in the formula (A1-5). Preferable examples of Rb and Rc are the same as Rb and Rc in the general formula ss-1.

The monoanionic bidentate ligand represented by the general formula (A1-5) and the phosphorescent metal complex containing a metal having an atomic valence of 40 or more in the present invention are preferably phosphorescent metal complexes represented by the following general formula (A10) Do.

(In the general formula _{(A10), R 1a ~ R} 1i represents a hydrogen atom or a substituent independently. (XY) is the at least one portion ligands selected from the (I-1) ~ (I -14) And n represents an integer of 1 to 3.)

In the general formula (A10), it is preferred for R _1a ~ R _1i, it is preferable the same as those of R _1a ~ R _1i in the formula (A1-5).

(X-Y) is preferably an acetylacetonato ligand or a substituted acetylacetonato ligand.

From the viewpoint of ease of synthesis, n is preferably 3, but it is also preferable from the viewpoint of cost reduction that n is 1 to 2 and the ligand is replaced by an inexpensive subsidiary ligand.

When n is 3, the formula (A10) is represented by the following formula (A10-1).

(In the general formula (A10-1), R _1a to R _1i each independently represent a hydrogen atom or a substituent.)

In the general formula (A10-1), it is preferred for R _1a ~ R _1i, it is preferable the same as those of R _1a ~ R _1i in the formula (A1-5).

The phosphorescent metal complex represented by the general formula (A10) is particularly preferably represented by the following general formula (A11-1), (A11-2) or (A11-3).

In the general formulas (A11-1), (A11-2) and (A11-3), R _1a , R _1b , R _1d , R _1e , R _1g and R _1h each independently represent a hydrogen atom, an alkyl group, An aryl group, a cyano group, a fluorine atom, -OR _2a , -SR _2a , -NR _2a R _2b , -BR _2a R _2b or -SiR _2a R _2b R _2c . Each of R _2a to R _2c is independently a hydrocarbon group or a hydrocarbon group substituted with a hetero atom.

Rx and Rz each independently represents an alkyl group, a perfluoroalkyl group, a halogen atom, or an aryl group, and is preferably an alkyl group. Ry is preferably a hydrogen atom, an alkyl group, a perfluoroalkyl group, a halogen atom, or an aryl group, and is preferably a hydrogen atom.

Rw is preferably a hydrogen atom, an alkyl group, a perfluoroalkyl group, a halogen atom or an aryl, and is preferably a hydrogen atom.

Specific examples of the compound comprising a bidentate ligand represented by the general formula (A1-5) are illustrated below, but the present invention is not limited thereto.

The phosphorescent iridium complex containing a monoanionic bidentate ligand represented by the general formula (A1-5) can be synthesized by various methods such as the method described in, for example, US 2007/0190359 or US 2008/0297033 .

For example, the ligand or its dissociation product and a metal compound are dissolved in a solvent (for example, a halogen-based solvent, an alcohol-based solvent, an ether-based solvent, an ester-based solvent, a ketone-based solvent, a nitrile- (Various organic and inorganic bases such as sodium methoxide, t-butoxypotassium, t-butoxyphenylacetate, etc.) in the presence or absence of a solvent in the presence of a base Triethylamine, potassium carbonate, etc.) or in the presence of a base, at room temperature or below, or by heating (microwave heating in addition to normal heating is also effective). Specifically, 7-methylimidazophenanthridine can be synthesized by the synthesis method described in [0132] to [0134] of U.S. Published Patent Application No. 0190359, After the synthesis, it is preferable to carry out purification by column chromatography, recrystallization and the like, and then purify by sublimation purification. Not only the organic impurities can be separated by the sublimation purification, but also inorganic salts and residual solvents can be effectively removed.

In the present invention, the phosphorescent iridium complex containing the compound represented by the general formula (T-1) or the monoanionic bidentate ligand represented by the general formula (A1-5) is contained in the luminescent layer, But may be further contained in any layer in the organic layer.

In the present invention, it is more preferable to include the compound represented by the general formula (1) to (3) and the compound represented by the general formula (T-1) in the luminescent layer in order to further suppress the change in chromaticity upon high-

The light-emitting material in the light-emitting layer is contained in an amount of 1% by mass to 50% by mass with respect to the mass of the entire compound forming the light-emitting layer in the light-emitting layer. It is preferably contained in an amount of 3% by mass to 20% by mass from the viewpoints of durability and external quantum efficiency, And more preferably from 15% by mass to 15% by mass.

Although the thickness of the light emitting layer is not particularly limited, it is preferably from 2 nm to 500 nm, and more preferably from 3 nm to 200 nm from the viewpoint of external quantum efficiency, more preferably from 5 nm to 100 nm desirable.

The light-emitting layer in the element of the present invention may be composed solely of a light-emitting material, or may be a mixed layer of a host material and a light-emitting material. The light emitting material may be a fluorescent light emitting material or a phosphorescent light emitting material, and one kind of dopant or two or more kinds of dopants may be used. The host material is preferably a charge-transporting material. One kind of host material may be used, or two or more types may be used, and for example, a structure in which an electron transporting host material and a hole transporting host material are mixed can be cited. Further, the light emitting layer may contain a material which does not have charge transportability and does not emit light.

The light-emitting layer may be a single layer or a multilayer of two or more layers. Each of the light emitting layers may emit light of different colors.

<Host material>

The host material used in the present invention is preferably a compound represented by any one of formulas (1) to (3).

The compounds represented by the general formulas (1) to (3) are compounds capable of transporting positive charges of positive holes and electrons.

As the host material used in the present invention, the following compounds may be contained in addition to the compounds represented by the general formulas (1) to (3).

The host material may be an electron transporting material and a hole transporting material, and is preferably a charge transporting material. One kind of host material may be used, or two or more types may be used, and for example, a structure in which an electron transporting host material and a hole transporting host material are mixed can be cited.

For example, there can be mentioned pyrrole, indole, carbazole (for example, CBP (4,4'-di (9-carbazoyl) biphenyl)), azaindole, azacarbazole, triazole, oxazole, oxadiazole Wherein the substituent is selected from the group consisting of a hydrogen atom, a hydroxyl group, a hydroxyl group, a hydroxyl group, a hydroxyl group, a hydroxyl group, a hydroxyl group, a hydroxyl group, A conductive polymer oligomer such as a tertiary amine compound, a styrylamine compound, a porphyrin compound, a polysilane compound, a poly (N-vinylcarbazole), an aniline copolymer, a thiophene oligomer or a polythiophene, A condensed aromatic hydrocarbon aromatic compound such as pyridine, pyrimidine, triazine, imidazole, pyrazole, triazole, oxazole, oxadiazole, fluorenone and triphenylene, anthraquinodimethane, anthrone, diphenylquinone , Thiopyran dioxide, carbodiimide, fluorenylidene dime , Distyryl pyrazine, fluorine-substituted aromatic compounds, heterocyclic tetracarboxylic acid anhydrides such as naphthalene perylene, phthalocyanine, metal complexes of 8-quinolinol derivatives, metal phthalocyanine, benzoxazole or benzothiazole as ligands And various metal complexes represented by complexes and derivatives thereof (which may have a substituent or a ring).

When the host material used in the present invention is combined with the compound represented by any one of formulas (1) to (3), the compound represented by the following formula (V) is preferable. The compound represented by the general formula (V) is superior in electron transportability as compared with a compound such as mCP commonly used as a host material of an organic electroluminescent device and can be obtained by combining with a compound represented by any of the general formulas (1) to (3) The charge transportability can be further enhanced.

In the general formula (V), o represents an integer of 1 to 3, preferably 2. When o represents 2 or 3, the partial structure bonded to the benzene ring is preferably substituted at the meta position with respect to the other partial structures.

In the present invention, when the compound represented by formula (V) is contained in the luminescent layer, the compound represented by formula (V) is preferably contained in the luminescent layer in an amount of 30 to 99 mass%, more preferably 40 to 97 mass% , And particularly preferably 50 to 95 mass%.

When the compound represented by the general formula (V) is introduced into a layer (for example, a charge transport layer or the like) other than the light emitting layer, it is preferably contained in the layer in an amount of 10% by mass to 100% by mass, more preferably 30% % Is more preferable.

In the light emitting layer in the present invention, the triplet minimum excitation energy (T ₁ energy) of the host material is preferably higher than the T ₁ energy of the phosphorescent material in terms of color purity, luminescence efficiency, and drive durability.

The content of the host compound in the present invention is not particularly limited, but it is preferably 15% by mass or more and 95% by mass or less with respect to the total mass of the compound forming the light-emitting layer from the viewpoints of light emission efficiency and drive voltage.

[Aromatic hydrocarbon compound]

The organic electroluminescent device of the present invention preferably has at least an organic layer between the light emitting layer and the cathode, and the organic layer contains an aromatic hydrocarbon compound.

It is more preferable that the aromatic hydrocarbon compound is contained in the organic layer adjacent to the light emitting layer between the light emitting layer and the cathode, but the use thereof is not limited and may be further contained in any layer in the organic layer. The introduction layer of the aromatic hydrocarbon compound according to the present invention may contain any one or more of a light emitting layer, a hole injecting layer, a hole transporting layer, an electron transporting layer, an electron injecting layer, an exciton blocking layer and a charge blocking layer.

The organic layer adjacent to the light emitting layer between the light emitting layer containing the aromatic hydrocarbon compound and the cathode is preferably a charge blocking layer or an electron transporting layer, more preferably an electron transporting layer.

The aromatic hydrocarbon compound is preferably composed only of carbon atoms and hydrogen atoms from the viewpoint of ease of synthesis.

When the aromatic hydrocarbon compound is contained in a layer other than the light-emitting layer, the content is preferably 70 to 100 mass%, more preferably 85 to 100 mass%. When the aromatic hydrocarbon compound is contained in the light emitting layer, it is preferably contained in an amount of 0.1 to 99 mass%, more preferably 1 to 95 mass%, and more preferably 10 to 95 mass%, relative to the total mass of the light emitting layer Do.

As the aromatic hydrocarbon compound, a hydrocarbon compound represented by the following general formula (Tp-1) (hereinafter sometimes simply referred to as &quot; hydrocarbon compound &quot;) is preferable.

The hydrocarbon compound represented by the general formula (Tp-1) is composed only of carbon atoms and hydrogen atoms, and is excellent in chemical stability, so that the driving durability is high and various changes during high-luminance driving are hardly caused.

The molecular weight of the hydrocarbon compound represented by the general formula (Tp-1) is preferably in the range of 400 to 1,200, more preferably 400 to 1,000, and still more preferably 400 to 800. When the molecular weight is 400 or more, a high-quality amorphous thin film can be formed. When the molecular weight is 1200 or less, the solubility in a solvent and the sublimation and deposition suitability are preferable.

The use of the hydrocarbon compound represented by the formula (Tp-1) is not limited, and may be added to any layer in the organic layer as well as the organic layer adjacent to the light-emitting layer.

(In the general formula (Tp-1), R ¹² to R ²³ each independently represent a phenyl group, a fluorenyl group or a fluorenyl group which may be substituted with a hydrogen atom, an alkyl group or an alkyl group, a phenyl group, a fluorenyl group, a naphthyl group or a triphenylenyl group , A naphthyl group, or a triphenylenyl group, provided that R ¹² to R ²³ are not all hydrogen atoms.

Examples of the alkyl group represented by R ¹² to R ²³ include a substituted or unsubstituted group such as a methyl group, ethyl group, isopropyl group, n-butyl group, tert-butyl group, n-octyl group, An ethyl group, an isopropyl group, a tert-butyl group and a cyclohexyl group, and more preferably a methyl group, an ethyl group or a tert-butyl group, and more preferably a methyl group, an ethyl group or a tert- -Butyl group.

R ¹² to R ²³ are preferably an alkyl group having 1 to 4 carbon atoms or an alkyl group having 1 to 4 carbon atoms, a phenyl group, a fluorenyl group, a naphthyl group, or a triphenylrenyl group A phenyl group, a fluorenyl group, a naphthyl group, or a triphenylenyl group) is more preferable.

A benzene ring which may be substituted with a phenyl group, a fluorenyl group, a naphthyl group or a triphenylrenyl group (which may further be substituted with an alkyl group, a phenyl group, a fluorenyl group, a naphthyl group or a triphenylenyl group) Particularly preferred.

The total number of aryl rings in the general formula (Tp-1) is preferably 2 to 8, more preferably 3 to 5. When the content is in this range, a high-quality amorphous thin film can be formed, and solubility in solvents, sublimation and deposition suitability are improved.

R ¹² to R ²³ each independently preferably have a total carbon number of 20 to 50, and more preferably 20 to 36 total carbon atoms. When the content is in this range, a high-quality amorphous thin film can be formed, and solubility in solvents, sublimation and deposition suitability are improved.

In one embodiment of the present invention, the hydrocarbon compound represented by the formula (Tp-1) is preferably a hydrocarbon compound represented by the following formula (Tp-2).

*

(In the general formula (Tp-2), a plurality of Ar ^{1 s} are the same, and a phenyl group, a fluorenyl group, a naphthyl group or a triphenylenyl group which may be substituted with an alkyl group, a phenyl group, a fluorenyl group, a naphthyl group or a triphenylenyl group .

Examples of the phenyl group, fluorenyl group, naphthyl group or triphenylenyl group which may be substituted with an alkyl group and an alkyl group represented by Ar ¹ , a phenyl group, a fluorenyl group, a naphthyl group or a triphenylenyl group include the groups represented by R ¹² to R ²³ And the preferable ones are the same.

In another aspect of the present invention, the hydrocarbon compound represented by the formula (Tp-1) is preferably a hydrocarbon compound represented by the following formula (Tp-3).

(In the general formula (Tp-3), L represents a phenyl group, a fluorenyl group, a naphthyl group, a triphenylenyl group, or a combination thereof, which may be substituted with an alkyl group, a phenyl group, a fluorenyl group, a naphthyl group or a triphenylenyl group n represents an integer of 1 to 6.)

Examples of the alkyl group, phenyl group, fluorenyl group, naphthyl group or triphenylenyl group forming an n-valent linking group represented by L are the same as those exemplified for R ¹² to R ²³ .

L is preferably a benzene ring optionally substituted with an alkyl group or a benzene ring, a fluorene ring, or an n-valent linking group formed by combining these rings.

Specific preferred examples of L are given below, but the present invention is not limited thereto. Also, * in the specific examples is bonded to the triphenylene ring.

n is preferably 1 to 5, more preferably 1 to 4.

In another aspect of the present invention, the hydrocarbon compound represented by the formula (Tp-1) is preferably a hydrocarbon compound represented by the following formula (Tp-4).

(In the formula (Tp-4), a plurality of Ar ^{2 s} are the same, and Ar ² represents a group substituted by an alkyl group, a phenyl group, a naphthyl group, a triphenylenyl group, or a combination thereof. Independently represent 0 or 1, and p and q are not 0 at the same time. When p and q represent 0, Ar ² represents a hydrogen atom.)

Ar ² is preferably a group consisting of a combination of an alkyl group having 1 to 4 carbon atoms, a phenyl group, a naphthyl group and a triphenylenyl group, more preferably a combination of a methyl group, a t-butyl group, a phenyl group and a triphenylenyl group .

Ar ² is particularly preferably a benzene ring substituted at the meta position by an alkyl group having 1 to 4 carbon atoms, a phenyl group, a naphthyl group, a triphenylenyl group, or a combination thereof.

When the hydrocarbon compound according to the present invention is used as a host material of the light emitting layer of the organic electroluminescence device or a layer adjacent to the light emitting layer, the energy gap in the thin film state (in the case of a phosphorescent material, , The energy of the lowest excitation triplet (T ₁ ) in the thin film state) is large, the emission is prevented from being quenched, which is advantageous for improving the efficiency. On the other hand, from the viewpoint of the chemical stability of the compound, it is preferable that the energy gap and the T ₁ energy are not too large. The T ₁ energy in the film state of the hydrocarbon compound represented by the general formula (Tp-1) is preferably 52 kcal / mol or more and 80 kcal / mol or less, more preferably 55 kcal / mol or more and 68 kcal / mol or less, kcal / mol or more and 63 kcal / mol or less. In particular, when a phosphorescence emitting material is used as a light emitting material, it is preferable that the T ₁ energy is in the above range.

The T ₁ energy can be obtained by the same method as that described in the above-mentioned general formulas (1) to (3).

Specific examples of the hydrocarbon compound related to the present invention are illustrated below, but the present invention is not limited thereto.

The compounds exemplified as the hydrocarbon compounds according to the present invention are described in WO 05/013388, WO 06/130598, WO 09/021107, US 2009/0009065, WO 09 / 008311 and WO 04/018587, the disclosures of which are incorporated herein by reference.

After the synthesis, it is preferable to carry out purification by column chromatography, recrystallization and the like, and then purify by sublimation purification. Not only the organic impurities can be separated by the sublimation purification, but also inorganic salts and residual solvents can be effectively removed.

In the light emitting device of the present invention, the hydrocarbon compound is contained in the organic layer adjacent to the light emitting layer between the light emitting layer and the cathode, but its use is not limited, and may be further contained in any layer in the organic layer. The introduction layer of the hydrocarbon compound according to the present invention may contain any one or more of a light emitting layer, a hole injecting layer, a hole transporting layer, an electron transporting layer, an electron injecting layer, an exciton blocking layer and a charge blocking layer.

The organic layer adjacent to the light emitting layer between the light emitting layer containing the hydrocarbon compound and the cathode is preferably a charge blocking layer or an electron transporting layer, more preferably an electron transporting layer.

The glass transition temperature (Tg) of the hydrocarbon compound according to the present invention is preferably 60 ° C or more and 400 ° C or less, more preferably 65 ° C or more and 300 ° C or less, More preferably 80 deg. C or more and 180 deg. C or less.

It is preferable that the light emitting element of the present invention includes at least one organic layer between the light emitting layer and the cathode and that the organic layer contains at least one compound represented by the following general formula (O-1) And is preferable from the viewpoint of luminous efficiency. The general formula (O-1) is described below.

(In the formula (O-1), R ^O1 represents an alkyl group, an aryl group or a heteroaryl group, A ^O1 to A ^O4 each independently represent a CR ^A or a nitrogen atom, R ^A represents a hydrogen atom, an alkyl group, Or a heteroaryl group, and plural R ^A may be the same or different, L ^O1 represents a divalent to 6-valent linking group consisting of an aryl ring or a heteroaryl ring, and n ^O1 represents an integer of 2 to 6.)

R ^O1 represents an alkyl group (preferably having 1 to 8 carbon atoms), an aryl group (preferably having 6 to 30 carbon atoms) or a heteroaryl group (preferably having 4 to 12 carbon atoms) do. R ^O1 is preferably an aryl group or a heteroaryl group, more preferably an aryl group. In the case where the aryl group of R ^O1 has a substituent, preferable substituents include an alkyl group, an aryl group or a cyano group, more preferably an alkyl group or an aryl group, and still more preferably an aryl group. When the aryl group of R ^O1 has plural substituents, the plural substituents may be bonded to each other to form a 5 or 6-membered ring. The aryl group of R ^O1 is preferably a phenyl group which may have a substituent Z ', more preferably a phenyl group which may be substituted with an alkyl group or an aryl group, still more preferably an unsubstituted phenyl group or a 2-phenylphenyl group.

A ^O1 to A ^O4 each independently represent a CR ^A or a nitrogen atom. Of ^A01 to ^A04 , 0 to 2 are preferably nitrogen atoms, and 0 or 1 is more preferably a nitrogen atom. It is preferable that A ^O1 to A ^{O4 are} all CR ^A or A ^O1 is a nitrogen atom and A ^O2 to A ^O4 are preferably CR ^A and it is preferable that A ^O1 is a nitrogen atom and A ^O2 to A ^O4 are CR ^A It is more preferable that A ^O1 is a nitrogen atom, A ^O2 to A ^O4 are CR ^A , and R ^A is a hydrogen atom.

R ^A represents a hydrogen atom, an alkyl group (preferably having 1 to 8 carbon atoms), an aryl group (preferably having 6 to 30 carbon atoms) or a heteroaryl group (preferably having 4 to 12 carbon atoms) . The plural R ^A may be the same or different. R ^A is preferably a hydrogen atom or an alkyl group, more preferably a hydrogen atom.

L ^O1 represents a divalent to hexavalent linking group consisting of an aryl ring (preferably having 6 to 30 carbon atoms) or a heteroaryl ring (preferably having 4 to 12 carbon atoms). As L ^O1 , preferably an arylene group, a heteroarylene group, an aryltriyl group or a heteroaryltriyl group, more preferably a phenylene group, a biphenylene group or a benzenetriyl group, more preferably a biphenylene group or a benzenetriyl group to be. L ^O1 may have the above-mentioned substituent Z ', and as the substituent having a substituent, an alkyl group, an aryl group or a cyano group is preferable. Specific examples of L ^O1 include the following.

n ^O1 represents an integer of 2 to 6, preferably an integer of 2 to 4, more preferably 2 or 3. n ^O1 is most preferably 3 from the standpoint of device efficiency and is most preferably 2 from the viewpoint of durability of the device.

The compound represented by the general formula (O-1) is more preferably a compound represented by the following general formula (O-2).

(O-2), R ^O1 represents an alkyl group, an aryl group or a heteroaryl group, R ^O2 to R ^O4 each independently represent a hydrogen atom, an alkyl group, an aryl group or a heteroaryl group, A ^O1 to A ^O4 each independently represents a nitrogen atom or CR ^a. R ^a represents a hydrogen atom, an alkyl group, an aryl group or a heteroaryl group, a plurality of R ^a is may be the same or different.)

R ^O1 and A ^O1 ~ ^O4 A is the formula (O1) of the R ^O1 and A ^O1 ~ ^O4 same meanings as A, it is also the preferable range thereof is also the same.

Each of R ^O2 to R ^O4 independently represents a hydrogen atom, an alkyl group (preferably having 1 to 8 carbon atoms), an aryl group (preferably having 6 to 30 carbon atoms) or a heteroaryl group (preferably having 4 to 12 carbon atoms) These may have substituent Z 'described above. R ^O2 to R ^O4 are preferably a hydrogen atom, an alkyl group or an aryl group, more preferably a hydrogen atom or an aryl group, and most preferably a hydrogen atom.

The compound represented by the above general formula (O-1) has a glass transition temperature (Tg) of 80 ° C to 300 ° C from the viewpoints of stability at high temperature storage and stable operation against heat generation during driving at high temperature More preferably 100 占 폚 to 300 占 폚, further preferably 120 占 폚 to 300 占 폚, and even more preferably 130 占 폚 to 300 占 폚.

Specific examples of the compound represented by formula (O-1) are shown below, but the present invention is not limited thereto.

The compound represented by the above general formula (O-1) can be synthesized by the method described in JP-A-2001-335776. After the synthesis, it is preferable to perform purification by column chromatography, recrystallization, reprecipitation or the like, and then purification by sublimation purification. Not only the organic impurities can be separated by the sublimation purification, but also the inorganic salts, residual solvent, water and the like can be effectively removed.

In the light emitting device of the present invention, the compound represented by the general formula (O-1) is contained in the organic layer between the light emitting layer and the cathode, but is preferably contained in the layer on the cathode side adjacent to the light emitting layer.

(Charge transport layer)

The charge transport layer refers to a layer in which charge transfer occurs when a voltage is applied to the organic electroluminescent device. Specifically, a hole injecting layer, a hole transporting layer, an electron blocking layer, a light emitting layer, a hole blocking layer, an electron transporting layer, or an electron injecting layer can be given. A hole injecting layer, a hole transporting layer, an electron blocking layer, or a light emitting layer. If the charge transporting layer formed by the coating method is a hole injecting layer, a hole transporting layer, an electron blocking layer, or a light emitting layer, an organic electroluminescent device with low cost and high efficiency can be manufactured. The charge transport layer is more preferably a hole injection layer, a hole transport layer, or an electronic block layer.

(Hole injection layer, hole transport layer)

The hole injection layer and the hole transport layer are layers having a function of receiving holes from the anode or the anode side and transporting them to the cathode side.

In the present invention, it is preferable to include a hole injection layer or a hole transport layer containing an electron-accepting dopant as an organic layer.

The metal complex represented by the aforementioned general formula (T-1) may be used in the hole injection layer or the hole transport layer.

(Electron injection layer, electron transport layer)

The electron injection layer and the electron transport layer are layers having a function of receiving electrons from the cathode or the cathode side and transporting them to the anode side. The electron injecting material and electron transporting material used in these layers may be a low molecular compound or a high molecular compound.

The hole injecting layer, the hole transporting layer, the electron injecting layer and the electron transporting layer are described in detail in, for example, JP-A-2008-270736 and JP-A-2007-266458. And can be applied to the invention.

The hole injecting layer, the hole transporting layer, the electron injecting layer, and the electron transporting layer are described in detail in Japanese Patent Laid-Open Publication No. 2008-270736 [0165] to [0167], and the matters described in these publications can be applied to the present invention .

(Hole blocking layer)

The hole blocking layer is a layer having a function of preventing the holes transported from the anode side to the light emitting layer from escaping to the cathode side. In the present invention, a hole blocking layer can be formed as an organic layer adjacent to the light emitting layer and the cathode side.

Examples of the organic compound constituting the hole blocking layer include an aluminum compound such as aluminum (III) bis (2-methyl-8-quinolinato) 4-phenyl phenolate (III) bis (2-methyl-8-quinolinato) 4-phenylphenolate (hereinafter abbreviated as BAlq)), triazole derivatives, 2,9- Phenanthroline derivatives such as 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (hereinafter abbreviated as BCP), and the like.

The thickness of the hole blocking layer is preferably 1 nm to 500 nm, more preferably 5 nm to 200 nm, and even more preferably 10 nm to 100 nm.

The hole blocking layer may have a single layer structure composed of one or more of the above-described materials, or a multilayer structure composed of plural layers of the same composition or different compositions.

(Electronic block layer)

The electron blocking layer is a layer having a function of preventing electrons transported from the cathode side to the light emitting layer from escaping to the anode side. In the present invention, an electron blocking layer can be formed as an organic layer adjacent to the light emitting layer and the anode side.

As examples of the organic compound constituting the electron blocking layer, those exemplified as the above-mentioned hole transporting materials can be applied.

The thickness of the electron blocking layer is preferably 1 nm to 500 nm, more preferably 5 nm to 200 nm, and even more preferably 10 nm to 100 nm.

The electronic block layer may have a single layer structure composed of one or more of the above-described materials, or a multi-layer structure composed of plural layers of the same composition or different composition.

In the organic electroluminescent device of the present invention, it is preferable that the electrode includes an anode, and an organic layer exists between the light emitting layer and the anode. The organic layer adjacent to the light-emitting layer preferably contains a compound having a minimum excitation triplet excitation (T ₁ ) energy of 58 kcal / mol or more in the solution, and preferably contains a compound having 62 kcal / mol to 75 kcal / mol desirable. As the compound having the lowest excitation triplet (T ₁ ) energy of 58 kcal / mol or more, a carbazole compound can be exemplified.

The carbazole compound is preferably a carbazole compound represented by the following formula (a).

(In the general formula (a), R ^a represents ^a substituent which may be substituted with a hydrogen atom of the skeleton, and when ^a plurality of R ^a exist, they may be the same or different.) N represents an integer of 0 to 8. )

When the compound represented by the general formula (a) is used in the charge transporting layer, the compound represented by the general formula (a) is preferably contained in an amount of 50 to 100 mass%, more preferably 80 to 100 mass% Particularly preferably 100% by mass.

When a compound represented by the general formula (a) is used for a plurality of organic layers, it is preferable that each layer contains the above-mentioned range.

The compound represented by the general formula (a) may contain only one kind in any organic layer, or may contain a plurality of compounds represented by the general formula (a) in any combination.

The thickness of the charge transport layer containing the compound represented by formula (a) is preferably from 1 nm to 500 nm, more preferably from 3 nm to 200 nm, and further preferably from 5 nm to 100 nm. The charge transport layer is preferably formed in contact with the light emitting layer.

The charge transporting layer may have a single layer structure composed of one or more of the above-described materials, or a multilayer structure composed of plural layers of the same composition or different composition.

Specific examples of the substituent represented by R ^a include a halogen atom, an alkoxy group, a cyano group, a nitro group, an alkyl group, an aryl group and an aromatic heterocyclic group, and examples thereof include an alkyl group having 10 or less carbon atoms, a substituted or unsubstituted An aryl group is preferable, and an alkyl group having 6 or less carbon atoms is more preferable.

n represents an integer of 0 to 8, preferably 0 to 4, more preferably 0 to 2.

The hydrogen atom constituting the general formula (a) also includes isotopes of hydrogen (deuterium atoms and the like). In this case, all of the hydrogen atoms in the compound may be substituted with hydrogen isotopes, or a mixture in which a part of the compounds includes hydrogen isotopes.

The compound represented by the general formula (a) can be synthesized by combining various known synthetic methods. Most commonly, the carbazole compound is synthesized by dehydrogenation (LFTieze, Th.Eicher, Takano, Ogasawara translation, precise organic synthesis) after azacophage reaction of a condensate of arylhydrazine and cyclohexane derivative Synthesis, 339 pages (published by Nankodo)). The coupling reaction using the obtained carbazole compound and a halogenated aryl compound using a palladium catalyst is described in Tetrahedron Letters, vol. 39, p. 617 (1998), vol. 39, pp. 2367 (1998) 6393 (1999), and the like. The reaction temperature and the reaction time are not particularly limited, and the conditions described in the above documents can be applied.

The compound represented by the general formula (a) of the present invention is preferably formed into a thin layer by a vacuum deposition process, but a wet process such as solution coating can also be preferably used. The molecular weight of the compound is preferably 2000 or less, more preferably 1200 or less, and particularly preferably 800 or less, from the viewpoint of suitability for deposition and solubility. Further, from the viewpoint of the deposition suitability, when the molecular weight is too small, the vapor pressure becomes small, and the change from the gas phase to the solid phase does not occur and it becomes difficult to form the organic layer.

Specific examples of the compound represented by formula (a) in the present invention are illustrated below, but the present invention is not limited thereto.

(Protective layer)

In the present invention, the entire organic EL device may be protected by a protective layer.

The material contained in the protective layer may be any material having a function of suppressing the entry of moisture, oxygen, or the like into the device for promoting deterioration of the device.

As for the protective layer, the matters described in paragraphs [0169] to [0170] of JP-A No. 2008-270736 can be applied to the present invention.

(Sealed container)

The device of the present invention may be used to seal the entire device using a sealed container.

As for the sealed container, the matters described in the paragraph [0171] of Japanese Patent Application Laid-Open No. 2008-270736 can be applied to the present invention.

In addition, a water absorbent or an inert liquid may be sealed in a space between the sealing container and the light emitting element. The water absorbing agent is not particularly limited, and examples thereof include barium oxide, sodium oxide, potassium oxide, calcium oxide, sodium sulfate, calcium sulfate, magnesium sulfate, phosphorus pentoxide, calcium chloride, magnesium chloride, , Calcium bromide, vanadium bromide, molecular sieve, zeolite, magnesium oxide and the like. Examples of the inert liquid include, but are not limited to, paraffins, liquid paraffins, fluorine-based solvents such as perfluoroalkane, perfluoroamine, and perfluoroether, chlorinated solvents, and silicone oils.

(Driving)

In the organic electroluminescent device of the present invention, light emission can be obtained by applying a direct current (may include an alternating current component if necessary) voltage (usually 2 volts to 15 volts) or a direct current between the anode and the cathode.

The driving method of the organic electroluminescent device of the present invention is disclosed in Japanese Laid-Open Patent Publication Nos. 2-148687, 6-301355, 5-29080, 7-134558, 8-234685, 8- 241047, Japanese Patent No. 2784615, U.S. Patent Nos. 5828429 and 6023308, and the like can be applied.

The external quantum efficiency of the organic electroluminescent device of the present invention is preferably 5% or more, more preferably 7% or more. The value of the external quantum efficiency can be the maximum value of the external quantum efficiency when the device is driven at 20 ° C or the value of the external quantum efficiency at 100 to 300 cd / m 2 when the device is driven at 20 ° C .

The internal quantum efficiency of the organic electroluminescent device of the present invention is preferably 30% or more, more preferably 50% or more, still more preferably 70% or more. The internal quantum efficiency of the device is calculated by dividing the external quantum efficiency by the light extraction efficiency. The light extraction efficiency is about 20% in a conventional organic EL device. However, by studying the shape of the substrate, the shape of the electrode, the thickness of the organic layer, the thickness of the inorganic layer, the refractive index of the organic layer, 20% or more.

The organic electroluminescent device of the present invention preferably has a maximum emission wavelength (maximum intensity wavelength of emission spectrum) of 350 nm or more and 700 nm or less, more preferably 450 nm or more and 600 nm or less, still more preferably 470 nm or more 580 nm or less, particularly preferably 490 nm or more and 550 nm or less.

(Use of the Light-emitting Element of the Present Invention)

The light emitting device of the present invention can be suitably used for a light emitting device, a pixel, a display device, a display, a backlight, an electronic photograph, an illumination light source, a recording light source, an exposure light source, a reading light source, Particularly, it is preferably used for a device that is driven in a region where the light emission luminance is high, such as a lighting device or a display device.

(Light emitting device)

Next, the light emitting device of the present invention will be described with reference to Fig.

The light emitting device of the present invention is formed using the organic electroluminescent device.

2 is a cross-sectional view schematically showing an example of the light emitting device of the present invention.

2 includes a transparent substrate 2 (a support substrate), an organic electroluminescence device 10, a sealing container 16, and the like.

The organic electroluminescent device 10 is constituted by sequentially laminating an anode 3 (first electrode), an organic layer 11, and a cathode 9 (second electrode) on a substrate 2. A protective layer 12 is laminated on the cathode 9 and a sealing container 16 is formed on the protective layer 12 with an adhesive layer 14 interposed therebetween. Further, a part of each of the electrodes 3 and 9, a partition wall, an insulating layer, and the like are omitted.

As the adhesive layer 14, a photo-curable adhesive such as an epoxy resin or a thermosetting adhesive may be used. For example, a thermosetting adhesive sheet may be used.

The use of the light-emitting device of the present invention is not particularly limited, and for example, a display device such as a television, a personal computer, a cellular phone, and an electronic paper may be used in addition to a lighting device.

(Lighting device)

Next, a lighting apparatus according to an embodiment of the present invention will be described with reference to Fig.

3 is a cross-sectional view schematically showing an example of a lighting apparatus according to an embodiment of the present invention.

As shown in Fig. 3, the illumination device 40 according to the embodiment of the present invention is provided with the above-described organic EL element 10 and the light scattering member 30. As shown in Fig. More specifically, the illumination device 40 is configured so that the substrate 2 of the organic EL element 10 and the light-scattering member 30 are in contact with each other.

The light scattering member 30 is not particularly limited as long as it can scatter light. In FIG. 3, the light scattering member 30 is a member in which the fine particles 32 are dispersed in the transparent substrate 31. As the transparent substrate 31, for example, a glass substrate can be preferably exemplified. As the fine particles 32, transparent resin fine particles can be preferably exemplified. As the glass substrate and transparent resin fine particles, all known ones can be used. When the light emitted from the organic electroluminescent element 10 is incident on the light incident surface 30A of the scattering member 30, the incident light is scattered by the light scattering member 30, Is emitted from the light exit surface 30B as illumination light.

Example

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited thereto. In particular, the presence or absence of a substituent has little effect on the effect of the present invention, and the same effect can be obtained even when the compound used in the following examples has a substituent.

The compounds represented by the above-mentioned general formulas (1) to (3) used in the examples were synthesized with reference to paragraph 47 and the like of Patent Document 4.

Compounds represented by the general formula (Tp-1) were synthesized by referring to the pamphlets of WO 05/013388, WO 06/130598 and WO 09/021107.

The organic materials used in this example were all purified and purified by high performance liquid chromatography (Toso TSKgel ODS-100Z) to have an absorption intensity area ratio of 254 nm of 99.9% or more.

&Lt; Example 1 >

[Fabrication of device]

A glass substrate (surface resistance 10 Ω / □) having an ITO film with a thickness of 0.5 mm and a width of 2.5 cm was placed in a cleaning container, subjected to ultrasonic cleaning in 2-propanol, and then subjected to UV-ozone treatment for 30 minutes . The following organic layers were sequentially deposited on the transparent anode (ITO film) by vacuum evaporation.

First layer: CuPc: film thickness 10 nm

Second layer: NPD: film thickness 30 nm

Layer 4: host material and Ir-1 (weight ratio 93: 7) shown in Table 1: film thickness 30 nm

Layer 6: Alq: film thickness 30 nm

* 0.1 nm of lithium fluoride and 100 nm of metallic aluminum were deposited in this order to form a negative electrode.

This laminate was placed in a glove box substituted with nitrogen gas without being brought into contact with the atmosphere, and sealed with a glass sealing can and an ultraviolet curable adhesive (XNR5516HV, manufactured by Nagasechiba Co., Ltd.) to obtain an organic electroluminescent device.

As a result of luminescence of these devices, luminescence derived from the luminescent material was obtained for each device.

(Performance Evaluation of Organic Electroluminescent Device)

The obtained devices were evaluated in terms of efficiency, durability, and chromaticity change during high current driving. Various measurements were performed as follows. The results are shown in Table 1.

In Tables 1 to 5, the symbol &quot; &quot; in the evaluation of chromaticity change means an inequality. For example, &quot; <0.005 &quot; means that the chromaticity change was less than 0.005.

(a) Efficiency

A direct current voltage was applied to each device using a source major unit 2400 manufactured by Toyotecnica to emit light, and the luminance was measured using a luminance system BM-8 manufactured by Topcon Corporation. The emission spectrum and the emission wavelength were measured using Spectrum Analyzer PMA-11 manufactured by Hamamatsu Hotton. Based on these values, the external quantum efficiency at a luminance of around 1000 cd / m 2 was calculated by the luminance conversion method, and the value of the element 1-1 of the present invention was taken as 10, which was expressed as a relative value in each table (that is, The value of the device 1-1 of the present invention was taken as 10, and the relative value was shown in each table). The higher the number, the better the efficiency.

(b) Durability

Each device was continuously lighted by applying a DC voltage so that the luminance was 5000 cd / m &lt; 2 &gt;, and the required time until the luminance reached 4000 cd / m &lt; 2 &gt; was regarded as an index of durability. 10, respectively. (In other words, the value of the device 1-1 of the present invention is also referred to as 10 in the following examples. The higher the number, the better the durability.

(c) Chromaticity change during high current driving

A DC voltage was applied to each device so that the current density was 25 mA / cm &lt; 2 &gt; The difference between the x value and the y value of both is compared with the chromaticity (x, y) when the DC voltage is applied so that the chromaticity (x, y) at this time is 0.25 mA / And was used as an index of chromaticity change at the time of high-luminance driving. The smaller the value of? X and? Y is, the better.

As shown in Table 1, by using the material 1 to 10 of the present invention as the host material, it is possible to provide a device having high efficiency and excellent device durability. Further, even when driven at a high current density, since the emission color equivalent to that at the time of driving at a normal current density is maintained, the present invention is particularly useful for display applications such as televisions in which both low-luminance display and high-luminance display are required.

&Lt; Example 2 >

A device was manufactured in the same manner as in Example 1 except that the material shown in Table 2 was used as the light emitting material, and the device efficiency and durability were evaluated. The luminescent color in Table 2 was visually confirmed.

As shown in Table 2, in the device having the same luminescent color, the device using the iridium complex as compared with the platinum complex gave good results in both efficiency and durability.

&Lt; Example 3 >

Except that 5 nm of the third layer made of the third layer material shown in Table 3 was formed between the second layer and the fourth layer by the vacuum vapor deposition method and the host material of the fourth layer was used as the host material shown in Table 3 The device was manufactured in the same manner as in Example 1, and the durability was evaluated.

As shown in Table 3, when a carbazole material comprising H-1 to H-3 was used as the third layer, it was found that the durability was improved as compared with the case where the third layer was not present.

<Example 4>

Except that a third layer of the fifth layer made of the fifth layer material shown in Table 4 was formed to a thickness of 3 nm between the fourth layer and the sixth layer by a vacuum evaporation method and that the host material of the fourth layer was the host material shown in Table 4. [ The device was fabricated in the same manner as in Example 1, and the device efficiency and durability were evaluated.

As shown in Table 4, when E-1 to E-5 were used as the fifth layer, the efficiency and device durability were remarkably improved, and the effect was that E-1 and E-2 having triphenylene skeleton were used It was remarkable at that time.

When OM-1, 2, 8, and 12 were used as the fifth layer, the device efficiency was remarkably increased. It was also found that durability was improved when three different materials were used in comparison with OM-12.

&Lt; Example 5 >

A glass substrate (surface resistance 10 Ω / □) having an ITO film with a thickness of 0.5 mm and a width of 2.5 cm was placed in a cleaning container, subjected to ultrasonic cleaning in 2-propanol, and then subjected to UV-ozone treatment for 30 minutes . An aqueous solution of PEDOT (poly (3,4-ethylenedioxythiophene)) / PSS (polystyrene sulfonic acid) (Baytron P (standard product)) was spin-coated (4000 rpm, 60 seconds) on this transparent anode (ITO film) C for 10 minutes to form a hole transporting layer (thickness: 150 nm).

Subsequently, a toluene solution containing 1 mass% of the host material and 0.05 mass% of Ir-1 shown in Table 5 was spin-coated (2000 rpm, 60 seconds) on the hole transport layer to form a light emitting layer.

On this light emitting layer, Alq was deposited as an electron injecting layer by vacuum deposition at 20 nm. Further, lithium fluoride 0.1 nm and metal aluminum 100 nm were deposited in this order to form a negative electrode.

The laminate was placed in a glove box substituted with nitrogen gas without being brought into contact with the atmosphere and sealed with a glass sealing can and an ultraviolet curable adhesive (XNR5516HV, manufactured by Nagasechiba Co., Ltd.) 5-5 and comparative element 5-1 were obtained. The obtained device was evaluated in the same manner as the device 1-1 of the present invention. The results are shown in Table 5.

As shown in Table 5, it can be seen that the same effect can be obtained even when a device is manufactured by using a solution coating method.

The structures of the compounds used in the above Examples and Comparative Examples are shown below.

(1) The charge-transporting compound

Comparative Example Compound

Example Compound

(2) Other compounds

2… Board
3 ... anode
4… Hole injection layer
5 ... Hole transport layer
6 ... The light-
7 ... Hole block layer
8… Electron transport layer
9 ... cathode
10 ... Organic electroluminescent device
11 ... Organic layer
12 ... Protective layer
14 ... Adhesive layer
16 ... Sealed container
20 ... Light emitting device
30 ... Light scattering member
30A ... Light incidence plane
30B ... Light emitting surface
31 ... Transparent substrate
32 ... Particulate
40 ... Lighting device

Claims (14)

1. An organic electroluminescent device having on a substrate a pair of electrodes and at least one organic layer including a light emitting layer between the electrodes and at least one organic layer between the light emitting layer and the cathode,
At least one compound represented by the general formula (1) is contained in at least one organic layer containing a light emitting layer between the electrodes, and at least one organic layer between the light emitting layer and the cathode has at least one compound represented by the following general formula O-1): &lt; EMI ID =

(In the formula (1), R ₁ to R ₈ each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 30 carbon atoms, N, O, S, P, Si, , Wherein at least one of R ₁ to R ₈ is an electron-withdrawing group, and the electron-withdrawing group is a group selected from the group consisting of a cyano group Or a perfluoroalkyl group,
R _1a and R _1b are each independently selected from the group consisting of an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, an aryl group having 6 to 30 carbon atoms, N, O, S, P, Si, A cyano group, a nitro group, a halogen atom or an amino group having at least one heteroatom and having 5 to 8 carbon atoms,
and n _1a and n _1b each independently represent an integer of 0 to 4.)

(In the general formula (O-1), R ^O1 represents an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 30 carbon atoms, or at least one group selected from the group consisting of N, O, S, P, Si, A heteroaryl group having a hetero atom and having 4 to 12 carbon atoms,
A ^O1 to A ^O4 each independently represent a CR ^A or a nitrogen atom; R ^A represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 30 carbon atoms, or N, O, S, P, And Te, and a plurality of R ^A's may be the same or different and may be the same or different,
L ^O1 represents an aryl ring having 6 to 30 carbon atoms or a divalent to tetravalent heteroaryl ring having 4 to 12 carbon atoms and at least one hetero atom selected from the group consisting of N, O, S, P, Si, Se and Te, 6 &lt; / RTI &gt;
and n ^O1 represents an integer of 2 to 6.) The method according to claim 1,
Wherein the light emitting layer contains at least one compound represented by the general formula (1). 3. The method of claim 2,
Wherein the light emitting layer further contains a phosphorescent metal complex. The method of claim 3,
Wherein the phosphorescent metal complex is an iridium complex. 5. The method of claim 4,
Wherein the iridium complex is an iridium complex represented by the general formula (T-2):

In the general formula (T-2), R _T3 'to R _T6 ' and R _T3 to R _T6 each independently represent a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 4 to 7 carbon atoms, An alkenyl group having 2 to 30 carbon atoms, -CN, a perfluoroalkyl group having 1 to 8 carbon atoms, a trifluorovinyl group, -CO ₂ R _T , -C (O) R _T , -N (R _T ) ₂ , -NO ₂ , -OR _T , a halogen atom, an aryl group having 6 to 30 carbon atoms, or a group having 5 or more carbon atoms having at least one heteroatom selected from the group consisting of N, O, S, P, Si, To 8, and may further have a substituent Z,
R _{T3, T4} and also R, R and R _{T5 T6} is condensed to form a 4-7 membered ring to a dog of any two adjacent coupled to each other, and can take the condensed 4 ~ Z substituent in the 7-membered ring is more,
R _T3 'and _T6 R is _{-C (R T) 2 -C (} R T) 2 -, -CR T = CR T -, -C (R T) 2 -, -O-, -NR T -, - May be connected by a linking group selected from OC (R _T ) ₂ -, -NR _T -C (R _T ) ₂ - and -N = CR _T - to form a ring,
R _T is independently selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 30 carbon atoms, an alkynyl group having 2 to 30 carbon atoms, N, O, S, P, Si, Having at least one heteroatom selected from the group consisting of N, O, S, P, Si, Se and Te and having from 1 to 8 carbon atoms having at least one heteroatom, A heteroaryl group having 5 to 8 carbon atoms, further may have a substituent Z,
Z is a halogen atom, each independently, -R ', -OR', -N (R ') 2, -SR', -C (O) R ', -C (O) OR', -C (O) N _{(R ') 2, -CN,} -NO 2, -SO 2, -SOR', -SO 2 R ' or -SO ₃ R' represents a, R 'are each independently a hydrogen atom, an alkyl group having 1 to 8 carbon atoms At least one hetero atom selected from the group consisting of a perhaloalkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 30 carbon atoms, an alkynyl group having 2 to 30 carbon atoms, N, O, S, P, Si, A heteroaryl group having 1 to 8 carbon atoms, an aryl group having 6 to 30 carbon atoms, or a heteroaromatic group having 5 to 8 carbon atoms having at least one hetero atom selected from the group consisting of N, O, S, P, Si, An aryl group,
(XY) represents a minor ligand, m _T represents an integer of 1 to 3, n _T represents an integer of 0 to 2, and m _T + n _T represents 3. 6. The method of claim 5,
Wherein, in the general formula (T-2), (XY) is a monoanionic bidentate ligand having a phenylpyridine skeleton. The method according to claim 1,
An organic layer adjacent to the light emitting layer is provided between the light emitting layer and the cathode, and the organic layer contains an aromatic hydrocarbon compound. delete The method according to claim 1,
And at least one organic layer including a light emitting layer between the electrodes is formed by a solution coating process. A light emitting device using the organic electroluminescent device according to any one of claims 1 to 7 and 9. A display device using the organic electroluminescent device according to any one of claims 1 to 7 and 9. A lighting device using the organic electroluminescent device according to any one of claims 1 to 7 and 9.
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