WO2018186462A1

WO2018186462A1 - Fluorescent compound, organic material composition, light emitting film, organic electroluminescent element material, and organic electroluminescent element

Info

Publication number: WO2018186462A1
Application number: PCT/JP2018/014517
Authority: WO
Inventors: 山田　哲也; じん薛; 康生宮田
Original assignee: コニカミノルタ株式会社
Priority date: 2017-04-07
Filing date: 2018-04-05
Publication date: 2018-10-11
Also published as: JPWO2018186462A1

Abstract

The present invention addresses the problem of providing a fluorescent compound which is suppressed in concentration quenching in a solid state. A fluorescent compound according to the present invention is characterized by having a structure that is represented by general formula (1).

Description

Fluorescent compound, organic material composition, luminescent film, organic electroluminescent device material, and organic electroluminescent device

The present invention relates to a fluorescent compound, an organic material composition, a light-emitting film, an organic electroluminescent device material, and an organic electroluminescent device, and more specifically, a fluorescent compound and organic material composition that suppresses concentration quenching in a solid state. The present invention relates to a material, a light-emitting film, an organic electroluminescence element material, and an organic electroluminescence element.

An organic electroluminescence element (organic EL element) has a structure in which a light emitting layer containing a compound that emits light (hereinafter also referred to as “light emitting material”) is sandwiched between an anode and a cathode, and electrons and holes are included in the light emitting layer. This is an element that emits light by utilizing the emission of light (fluorescence / phosphorescence) when excitons are generated by injecting and recombining to generate excitons. The organic EL element can emit light at a low voltage of about several V to several tens V, and is a self-luminous type, has a wide viewing angle, has high visibility, and is a thin-film type completely solid element. Therefore, it attracts attention from the viewpoints of space saving and portability.

Various light emitting materials have been developed so far, and organometallic complexes represented by Ir complexes, aromatic hydrocarbons, and the like are known. Of these, aromatic hydrocarbons often emit fluorescence in solution, but in the solid state in which molecules are aggregated, they do not emit fluorescence due to concentration quenching and excimer formation, or from the time of solution. Also tended to show long wavelength light emission. Therefore, there has been a problem in use in organic EL devices and bioimaging.

For example, Patent Document 1 discloses a technique in which a dihedral angle between two molecules is increased by introducing a naphthyl group or a fluorenyl group as a substituent into a perylene ring, thereby suppressing excimer formation. However, this 4-substituted perylene has a problem that the fluorescence quantum yield is low when used in a single film.

International Publication No. 2010/064694

The present invention has been made in view of the above-described problems and situations, and the problem to be solved is a fluorescent compound, an organic material composition, a light-emitting film, an organic electroluminescence element material, and a material that suppress concentration quenching in a solid state. An organic electroluminescence device is provided.

In order to solve the above-mentioned problems, the present inventor adopts a fluorescent compound having a specific substituent in the process of examining the cause of the above-described problem, thereby suppressing the fluorescence quenching in the solid state. The present inventors have found that a compound, an organic material composition, a light-emitting film, an organic electroluminescence element material, and an organic electroluminescence element can be provided, and have reached the present invention.

That is, the above-mentioned problem according to the present invention is solved by the following means.

1. A fluorescent compound having a structure represented by the following general formula (1).

(In the general formula (1), X represents a π-conjugated condensed ring having a 14π electron system or more. Y represents a deuterium atom, halogen atom, cyano group, nitro group, hydroxy group, mercapto group, alkyl group, cycloalkyl group. Group, alkenyl group, alkynyl group, heterocyclic group, alkoxy group, cycloalkoxy group, aryloxy group, alkylthio group, cycloalkylthio group, arylthio group, alkoxycarbonyl group, aryloxycarbonyl group, sulfamoyl group, acyl group, acyloxy group Amide group, carbamoyl group, ureido group, sulfinyl group, alkylsulfonyl group, arylsulfonyl group, heteroarylsulfonyl group, amino group, fluorinated hydrocarbon group, triarylsilyl group, diarylalkylsilyl group, aryldialkylsilyl group, Trialkylsilyl group, An acid ester group, a phosphite group, a phosphono group, a phenyl group, or a group having a structure represented by the following general formula (2) is represented, and these may further have a substituent. At least one is a group having a structure represented by the following general formula (2): Y may be the same as or different from each other when there are a plurality of Y. n is the π-conjugated condensation. Represents the number of Ys that can be substituted for hydrogen atoms on the ring, and represents an integer from 1 to the maximum number.)

(In the general formula (2), R ¹ to R ⁵ are each independently a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a nitro group, a hydroxy group, a mercapto group, an alkyl group, a cycloalkyl group, or an alkenyl group. Alkynyl group, heterocyclic group, alkoxy group, cycloalkoxy group, aryloxy group, alkylthio group, cycloalkylthio group, arylthio group, alkoxycarbonyl group, aryloxycarbonyl group, sulfamoyl group, acyl group, acyloxy group, amide group, Carbamoyl group, ureido group, sulfinyl group, alkylsulfonyl group, arylsulfonyl group or heteroarylsulfonyl group, amino group, fluorinated hydrocarbon group, triarylsilyl group, diarylalkylsilyl group, aryldialkylsilyl group, trialkylsilyl group , Represents an ester group, a phosphite group, or a phosphono group, tables in at least one of these further may have a substituent .R ¹ and R ^5, the following general formula (3) or (4) * 1 represents a binding site with X.)

(In General Formula (3), A represents a carbon atom or a silicon atom. R ⁶ to R ⁸ each independently represents the same atom or substituent as R ¹ to R ⁵ in General Formula (2). However, at least one of R ⁶ to R ⁸ is an alkyl group having 1 or more carbon atoms. * 2 represents a bonding site with an adjacent atom.)

(In General Formula (4), R ⁹ and R ¹⁰ each independently represent the same atom or substituent as R ¹ to R ⁵ in General Formula (2), but at least one of them has 1 or more carbon atoms. * 3 represents a bonding site with an adjacent atom, R ¹ to R ¹⁰ in the general formulas (2) to (4) are substituted or unsubstituted aliphatic groups bonded to each other. A ring may be formed, but an aromatic ring is not further condensed to the formed aliphatic ring.)

2. The fluorescent compound according to item 1, wherein at least one of R ¹ and R ⁵ in the general formula (2) is represented by the general formula (3).

3. The fluorescent compound according to the first or second item, wherein the fluorescent compound having the structure represented by the general formula (1) has a structure represented by the following general formula (1a).

(In the general formula (1a), X represents a π-conjugated condensed ring having a 14π electron system or more. Y represents a deuterium atom, a triarylsilyl group, a diarylalkylsilyl group, an aryldialkylsilyl group, a trialkylsilyl group, A phenyl group or a group having a structure represented by the following general formula (2a), which may further have a substituent, wherein at least one of Y is represented by the following general formula (2a); Y may be the same or different when there are a plurality of groups, and n is the number of Ys that can be substituted for hydrogen atoms on the π-conjugated condensed ring. Represents an integer from 1 to the maximum number.)

(In the general formula (2a), R ¹ to R ⁵ each independently represent R ¹ to R ⁵ in the general formula (2) and an atom or a substituent, and at least one of R ¹ and R ⁵ is carbon. It is a linear, branched or cyclic alkyl group having two or more, or at least one of R ¹ and R ² and R ⁴ and R ⁵ is bonded to each other to form a substituted or unsubstituted aliphatic ring. (The aromatic ring is not further condensed to the aliphatic ring formed at this time.)

4. Any one of Items 1 to 3 wherein X in the general formula (1) or (1a) is a π-conjugated condensed ring having a structure represented by any one of the following general formulas (5) to (21) The fluorescent compound according to claim 1.

(In the general formulas (5) to (19), R represents a hydrogen atom or a bonding site with Y in the general formula (1) or (1a), but not all of them are hydrogen atoms. R may be the same as or different from each other.
In the general formulas (20) and (21), L represents —CR ¹¹ R ¹² —, —O—, —NR ¹³ —, —SiR ¹⁴ R ¹⁵ —, or —S—. The plurality of L may be the same as or different from each other. R and R ¹¹ to R ¹⁵ each independently represent a hydrogen atom or a bonding site with Y in the general formula (1) or (1a), but not all are hydrogen atoms. Several R may mutually be same or different. )

5. Any one of Items 1 to 3 wherein X in the general formula (1) or (1a) is a π-conjugated condensed ring having a structure represented by any one of the following general formulas (33) to (52) The fluorescent compound according to claim 1.

(In the general formulas (33) to (49), R represents a bonding site with Y in the general formula (1) or (1a). R may be the same or different from each other.
In the general formulas (50) to (52), L represents —CR ¹¹ R ¹² —, —O—, —NR ¹³ —, —SiR ¹⁴ R ¹⁵ —, or —S—. The plurality of L may be the same as or different from each other. R represents a binding site with Y in the general formula (1) or (1a). R ¹¹ to R ¹⁵ each independently represent a hydrogen atom or a bonding site with Y in the general formula (1) or (1a). The plurality of R and R ¹¹ to R ¹⁵ may be the same as or different from each other. )

6. Item 6. The fluorescent compound according to Item 5, wherein all Rs in the general formulas (33) to (52) are groups having a structure represented by the general formula (2a).

7. 6. The fluorescence according to item 5, wherein one of R in the general formulas (33) to (52) is a triarylsilyl group, and the other Rs are all groups having the structure represented by the general formula (2a). Luminescent compound.

8). R ¹ and R ⁵ in the general formula (2) or (2a) are represented by the general formula (3) or (4), respectively, and have different structures. The fluorescent compound according to any one of the above.

9. An organic material composition comprising the fluorescent compound according to any one of items 1 to 8, and a phosphorescent compound or a thermally activated delayed fluorescent compound.

10. An organic material composition comprising the fluorescent compound according to any one of items 1 to 8, a phosphorescent compound or a thermally activated delayed fluorescent compound, and a host compound.

11. A luminescent film comprising the fluorescent compound according to any one of items 1 to 8.

12. An organic electroluminescent element material containing a fluorescent compound having a structure represented by the following general formula (1).

(In General Formula (3), A represents a carbon atom or a silicon atom. R ⁶ to R ⁸ each independently represents R ¹ to R ⁵ in General Formula (2) and an atom or substituent, (At least one of R ⁶ to R ⁸ is an alkyl group having 1 or more carbon atoms. * 2 represents a bonding site with an adjacent atom.)

13. The organic electroluminescent element material according to item 12, wherein at least one of R ¹ and R ⁵ in the general formula (2) is represented by the general formula (3).

14. The organic electroluminescence device material according to item 12 or 13, wherein the fluorescent compound having the structure represented by the general formula (1) has a structure represented by the following general formula (1a).

(In the general formula (2a), R ¹ to R ⁵ each independently represent the same atom or substituent as R ¹ to R ⁵ in the general formula (2), but at least one of R ¹ and R ⁵ Is a linear, branched or cyclic alkyl group having 2 or more carbon atoms, or at least one of R ¹ and R ² and R ⁴ and R ⁵ is bonded to each other to form a substituted or unsubstituted aliphatic ring. (The aromatic ring is not further condensed to the aliphatic ring formed at this time.)

15. Any of paragraphs 12 to 14 wherein X in the general formula (1) or (1a) is a π-conjugated condensed ring having a structure represented by any of the following general formulas (5) to (21) The organic electroluminescence element material according to claim 1.

16. Any of paragraphs 12 to 14 wherein X in the general formula (1) or (1a) is a π-conjugated condensed ring having a structure represented by any of the following general formulas (33) to (52) The organic electroluminescence element material according to claim 1.

17. Item 17. The organic electroluminescence device material according to Item 16, wherein all Rs in the general formulas (33) to (52) are groups having a structure represented by the general formula (2a).

18. The organic compound according to item 16, wherein one of Rs in the general formulas (33) to (52) is a triarylsilyl group, and the other Rs are all groups having the structure represented by the general formula (2a). Electroluminescence element material.

19. R ¹² and R ⁵ in the general formula (2) or (2a) are represented by the general formula (3) or (4), respectively, and have different structures Organic electroluminescent element material as described in any one of these.

20. An organic electroluminescence device having an organic functional layer including at least a light emitting layer between an anode and a cathode,
The organic electroluminescent element in which the organic electroluminescent element material as described in any one of Claim 12 to 19th contains in the said organic functional layer.

The above-described means of the present invention can provide a fluorescent compound, an organic material composition, a luminescent film, an organic electroluminescent element material, and an organic electroluminescent element that suppress concentration quenching in a solid state.

The expression mechanism / action mechanism of the effect of the present invention is not clear, but is presumed as follows.

As a result of intensive studies, the present inventors have found that when a π-conjugated ring condensed ring having a 14π electron system or more has a substituent (phenyl group), at least one ortho position of the substituent (phenyl group). It has been found that the light-emitting property in the solution state can be maintained even in the solid state by having a substituent having a bulkiness higher than that of the ethyl group.

In order to suppress concentration quenching and excimer formation in the solid state, that is, to suppress spontaneous aggregation of molecules, ΔG may be controlled to be a negative value or a smaller value.
Here, ΔG is obtained by the following relational expression (1).

ΔG = ΔH−TΔS (1)

Here, G is Gibbs free energy, H is enthalpy, S is entropy, and T is absolute temperature.

In order to set ΔG to a negative value or a smaller value, it is conceivable to reduce ΔH or increase ΔS.
In the prior art, ΔG is controlled by introducing a group that becomes a steric hindrance to reduce intermolecular interaction and reducing ΔH. On the other hand, the present invention controls ΔG by increasing ΔS in addition to decreasing ΔH.

First, consider the contribution of ΔH. By adopting a benzene ring, which is a non-condensed aromatic hydrocarbon, as a substituent of the π-conjugated condensed ring (substituent Y in the general formula (1)), steric repulsion between benzene rings between molecules leads to π Intermolecular interaction between conjugated condensed rings can be reduced. That is, it can be considered that ΔG is reduced by reducing ΔH.
In addition, when the benzene ring has an aromatic substituent or is condensed with another aromatic ring, the π-plane is expanded, so that the intermolecular molecules between the substituted or condensed benzene rings It is considered that the contribution of interaction becomes large and ΔH is not reduced as a whole. Therefore, the substituent Y of the π-conjugated condensed ring is preferably a benzene ring that does not have an aromatic substituent, and is preferably a benzene ring that is not condensed with other aromatic rings.

Next, let us consider the contribution of ΔS. When a substituent having a bulkiness higher than that of the ethyl group is introduced into at least one ortho position of the phenyl group, the conformation of the substituent is suppressed while suppressing the rotation of the bond between the π-conjugated condensed ring and the phenyl group. ΔS can be increased by the presence of various conformational isomers.
For example, Japanese Patent No. 5557197 discloses a compound having a methyl group at the ortho position of the phenyl group. Although the rotation of the bond between the π-conjugated condensed ring and the phenyl group is suppressed due to the steric hindrance of the methyl group, the conformation isomer cannot be generated in the methyl group, so there is almost no contribution of ΔS to ΔG, and the contribution of ΔH. Is considered to be only.
On the other hand, when a substituent having a bulkiness higher than that of the ethyl group is introduced at the ortho position as in the present invention, the rotation of the bond between the π-conjugated condensed ring and the phenyl group is suppressed as in the case of the methyl group. In addition to the contribution of ΔH, the contribution of ΔS can be expected. This is because the structural freedom is high because innumerable conformations are generated by the rotation and vibration of the substituent.
Consider the ethyl group as an example. Of the two carbon atoms of the ethyl group, the carbon closer to the phenyl group, that is, the methylene group (—CH ₂ —) suppresses the rotation of the π-conjugated condensed ring and the phenyl group due to its steric hindrance, and as a result, ΔH Contributes to ΔG. On the other hand, the methyl group on the terminal side can freely rotate, but a relatively stable conformation is generated depending on the angle (twisted conformation). In the case of a longer-chain alkyl group such as a butyl group, more conformers such as Gauche and anti-periplanar exist. Actually, the stability of this conformation depends on the degree of freedom of rotation, that is, the conformational isomerism that cannot be observed spectroscopically, depending on the steric environment where the ethyl group is located. It can be considered to be distinguished. In any case, various conformations occur when the bulk is higher than the ethyl group, and ΔS can be increased by their contribution. In particular, in the present invention, it is considered that this increase in ΔS greatly contributes to reducing ΔG.

As described above, adopting a benzene ring as a substituent (decreasing ΔH), and disposing a substituent having a bulkiness higher than that of an ethyl group in at least one ortho position of the phenyl group (increasing ΔS). Thus, it is presumed that the light-emitting property in the solution state can be maintained even in the solid state.

Schematic perspective view showing an example of the configuration of the display device Schematic diagram of display section A shown in FIG. Schematic of lighting device Cross section of the lighting device

The fluorescent compound of the present invention has a structure represented by the general formula (1), and at least one Y has a structure represented by the general formula (2). This feature is a technical feature common to the inventions according to the following embodiments.

As an embodiment of the present invention, at least one of R ¹ and R ⁵ in the general formula (2) is represented by the general formula (3) or (4), and is particularly represented by the general formula (3). preferable. Further, it is preferable that R ¹ and R ⁵ in the general formula (2) have different structures respectively.

Further, the fluorescent compound having the structure represented by the general formula (1) has a structure represented by the general formula (1a) and at least one Y represented by the general formula (2a). preferable.

In addition, the π-conjugated condensed ring represented by X in the general formula (1) preferably has a structure represented by any one of the general formulas (5) to (21), and the general formulas (33) to (52 It is more preferable to have a structure represented by any one of
Further, all R in the general formulas (33) to (52) are groups having a structure represented by the general formula (2a), or one of R in the general formulas (33) to (52) is triaryl. It is a silyl group, and other R is preferably a group having a structure represented by the general formula (2a).

The present invention can provide an organic material composition containing the fluorescent compound and the phosphorescent compound or the thermally activated delayed fluorescent compound.

The present invention can provide an organic material composition containing the above-described fluorescent compound, a phosphorescent compound or a thermally activated delayed fluorescent compound, and a host compound.

The present invention can provide a luminescent film containing the fluorescent compound.

The present invention can provide an organic electroluminescent element material containing a fluorescent compound having a structure represented by the general formula (1).

The present invention provides an organic electroluminescent device having an organic functional layer including at least a light emitting layer between an anode and a cathode, wherein the organic functional layer contains the organic electroluminescent device material. it can.

Hereinafter, the present invention, its components, and modes and modes for carrying out the present invention will be described in detail. In the present application, “˜” representing a numerical range is used in the sense that numerical values described before and after the numerical value range are included as a lower limit value and an upper limit value.

<Fluorescent compound>
The fluorescent compound of the present invention has a structure represented by the following general formula (1).

In general formula (1), X represents a π-conjugated condensed ring having a 14π-electron system or more. Y is a deuterium atom, halogen atom, cyano group, nitro group, hydroxy group, mercapto group, alkyl group, cycloalkyl group, alkenyl group, alkynyl group, heterocyclic group, alkoxy group, cycloalkoxy group, aryloxy group, Alkylthio group, cycloalkylthio group, arylthio group, alkoxycarbonyl group, aryloxycarbonyl group, sulfamoyl group, acyl group, acyloxy group, amide group, carbamoyl group, ureido group, sulfinyl group, alkylsulfonyl group, arylsulfonyl group, heteroaryl Sulfonyl group, amino group, fluorinated hydrocarbon group, triarylsilyl group, diarylalkylsilyl group, aryldialkylsilyl group, trialkylsilyl group, phosphate ester group, phosphite ester group, phosphono group, phenyl group, Represents a group having the structure represented by the following general formula (2), which may have a substituent. At least one of Y is a group having a structure represented by the following general formula (2). When there are a plurality of Ys, they may be the same as or different from each other. n represents the number of Ys that can be substituted for the hydrogen atom on the π-conjugated condensed ring, and represents an integer from 1 to the maximum number.

Here, the π-conjugated condensed ring does not need to have aromaticity, but simply means that the entire ring has a conjugated structure.

X in the general formula (1) is not particularly limited as long as it is a π-conjugated condensed ring having 14 or more π electrons, but the following general formulas (5) to (5)-( Those having the structure represented by 32) are preferred.

In the general formulas (5) to (19) and (22) to (32), R represents a hydrogen atom or a bonding site with Y in the general formula (1), but not all are hydrogen atoms. Several R may mutually be same or different.
In the general formulas (20) and (21), L represents —CR ¹¹ R ¹² —, —O—, —NR ¹³ —, —SiR ¹⁴ R ¹⁵ —, or —S—. The plurality of L may be the same as or different from each other. R and R ¹¹ to R ¹⁵ each independently represent a hydrogen atom or a bonding site with Y in the general formula (1), but not all are hydrogen atoms. Several R may mutually be same or different.

Among these, X in the general formula (1) is more preferably a π-conjugated condensed ring having a structure represented by the general formulas (5) to (21).

In the general formulas (20) and (21), from the viewpoint of maintaining the fluorescence quantum yield in the film state, R ¹¹ to R ¹⁵ are linear, branched or cyclic alkyl groups, and any one of R is represented by the general formula It preferably has a group having the structure represented by (2).

Further, among the exemplified X, it is represented by the general formula (5), (7), (8), (13), (15) to (18) or (20) because of the high fluorescence quantum yield. A π-conjugated condensed ring having a structure is more preferable.
Furthermore, from the viewpoint of maintaining the fluorescence quantum yield in the film state, those having a substitution form as shown in the following general formulas (33) to (52) can be used particularly preferably.

In the general formulas (33) to (49), R represents a binding site with Y in the general formula (1) or (1a). R may be the same as or different from each other.
In the general formulas (50) to (52), L represents —CR ¹¹ R ¹² —, —O—, —NR ¹³ —, —SiR ¹⁴ R ¹⁵ —, or —S—. The plurality of L may be the same as or different from each other. R represents a binding site with Y in the general formula (1) or (1a). R ¹¹ to R ¹⁵ each independently represent a hydrogen atom or a bonding site with Y in formula (1) or (1a). The plurality of R and R ¹¹ to R ¹⁵ may be the same as or different from each other.

Specific examples of Y in the general formula (1) include a deuterium atom, a halogen atom (for example, a fluorine atom, a chlorine atom, a bromine atom, etc.), a cyano group, a nitro group, a hydroxy group, a mercapto group, an alkyl group ( For example, methyl group, ethyl group, propyl group, isopropyl group, tert-butyl group, pentyl group, hexyl group, octyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, etc.), cycloalkyl group (for example, cyclopentyl group) Cyclohexyl group etc.), alkenyl group (eg vinyl group, allyl group etc.), alkynyl group (eg ethynyl group, propargyl group etc.), heterocyclic group (eg pyrrolidyl group, imidazolidyl group, morpholyl group, oxazolidyl group etc.) ), Alkoxy group (for example, methoxy group, ethoxy group, propyloxy group, Nyloxy group, hexyloxy group, octyloxy group, dodecyloxy group, etc.), cycloalkoxy group (eg, cyclopentyloxy group, cyclohexyloxy group, etc.), aryloxy group (eg, phenoxy group, naphthyloxy group, etc.), alkylthio group (For example, methylthio group, ethylthio group, propylthio group, pentylthio group, hexylthio group, octylthio group, dodecylthio group, etc.), cycloalkylthio group (for example, cyclopentylthio group, cyclohexylthio group, etc.), arylthio group (for example, phenylthio group, Naphthylthio group, etc.), alkoxycarbonyl groups (eg, methyloxycarbonyl group, ethyloxycarbonyl group, butyloxycarbonyl group, octyloxycarbonyl group, dodecyloxycarbonyl group, etc.), ants Ruoxycarbonyl group (eg, phenyloxycarbonyl group, naphthyloxycarbonyl group, etc.), sulfamoyl group (eg, aminosulfonyl group, methylaminosulfonyl group, dimethylaminosulfonyl group, butylaminosulfonyl group, hexylaminosulfonyl group, cyclohexylamino) Sulfonyl group, octylaminosulfonyl group, dodecylaminosulfonyl group, phenylaminosulfonyl group, naphthylaminosulfonyl group, 2-pyridylaminosulfonyl group, etc.), acyl group (for example, acetyl group, ethylcarbonyl group, propylcarbonyl group, pentylcarbonyl group) Cyclohexylcarbonyl group, octylcarbonyl group, 2-ethylhexylcarbonyl group, dodecylcarbonyl group, phenylcarbonyl group, naphthylcarbonyl group , Pyridylcarbonyl group etc.), acyloxy group (eg acetyloxy group, ethylcarbonyloxy group, butylcarbonyloxy group, octylcarbonyloxy group, dodecylcarbonyloxy group, phenylcarbonyloxy group etc.), amide group (eg methylcarbonyl) Amino group, ethylcarbonylamino group, dimethylcarbonylamino group, propylcarbonylamino group, pentylcarbonylamino group, cyclohexylcarbonylamino group, 2-ethylhexylcarbonylamino group, octylcarbonylamino group, dodecylcarbonylamino group, phenylcarbonylamino group, Naphthylcarbonylamino group, etc.), carbamoyl group (eg, aminocarbonyl group, methylaminocarbonyl group, dimethylaminocarbonyl group, propylaminocarbonyl group) Bonyl group, pentylaminocarbonyl group, cyclohexylaminocarbonyl group, octylaminocarbonyl group, 2-ethylhexylaminocarbonyl group, dodecylaminocarbonyl group, phenylaminocarbonyl group, naphthylaminocarbonyl group, 2-pyridylaminocarbonyl group, etc.), ureido group (Eg, methylureido group, ethylureido group, pentylureido group, cyclohexylureido group, octylureido group, dodecylureido group, phenylureido group, naphthylureido group, 2-pyridylaminoureido group), sulfinyl group (eg, methylsulfinyl group) Ethylsulfinyl group, butylsulfinyl group, cyclohexylsulfinyl group, 2-ethylhexylsulfinyl group, dodecylsulfinyl group, phenylsulfuric group Nyl group, naphthylsulfinyl group, 2-pyridylsulfinyl group, etc.), alkylsulfonyl group (eg, methylsulfonyl group, ethylsulfonyl group, butylsulfonyl group, cyclohexylsulfonyl group, 2-ethylhexylsulfonyl group, dodecylsulfonyl group, etc.), aryl Sulfonyl group or heteroarylsulfonyl group (eg, phenylsulfonyl group, naphthylsulfonyl group, 2-pyridylsulfonyl group, etc.), amino group (eg, amino group, ethylamino group, dimethylamino group, butylamino group, cyclopentylamino group, 2-ethylhexylamino group, dodecylamino group, anilino group, naphthylamino group, 2-pyridylamino group, piperidyl group (also called piperidinyl group), 2,2,6,6-tetramethylpiperidinyl group), fluorine Hydrocarbon group (for example, fluoromethyl group, trifluoromethyl group, pentafluoroethyl group, pentafluorophenyl group, etc.), triarylsilyl group (for example, triphenylsilyl group, tri (4-methylphenyl) silyl group, Tri (3,5-dimethylphenyl) silyl group, etc.), diarylalkylsilyl groups (eg t-butyldiphenylsilyl group, isopropyldiphenylsilyl group etc.), aryldialkylsilyl groups (eg dimethylphenylsilyl group, isopropyldi ( 4-methylphenyl) silyl group, etc.), trialkylsilyl group (eg, trimethylsilyl group, triisopropylsilyl group, t-butyldimethylsilyl group, etc.), phosphate ester group (eg, dihexylphosphoryl group, etc.), phosphorous acid Ester groups (eg diphenylphos Iniru group), a phosphono group, a phenyl group, and the like. These substituents may be further substituted with the same substituents.

In general formula (2), R ¹ to R ⁵ are each independently a hydrogen atom, deuterium atom, halogen atom, cyano group, nitro group, hydroxy group, mercapto group, alkyl group, cycloalkyl group, alkenyl group, Alkynyl group, heterocyclic group, alkoxy group, cycloalkoxy group, aryloxy group, alkylthio group, cycloalkylthio group, arylthio group, alkoxycarbonyl group, aryloxycarbonyl group, sulfamoyl group, acyl group, acyloxy group, amide group, carbamoyl Group, ureido group, sulfinyl group, alkylsulfonyl group, arylsulfonyl group or heteroarylsulfonyl group, amino group, fluorinated hydrocarbon group, triarylsilyl group, diarylalkylsilyl group, aryldialkylsilyl group, trialkylsilyl group, Rin Ester group, a phosphite group, or a phosphono group, which may have a substituent. At least one of R ¹ and R ⁵ is a group having a structure represented by the following general formula (3) or (4). * 1 represents a binding site with X.

In general formula (3), A represents a carbon atom or a silicon atom. R ⁶ to R ⁸ each independently represents the same atom or substituent as R ¹ to R ⁵ in formula (2), but at least one of R ⁶ to R ⁸ is an alkyl group having 1 or more carbon atoms It is. * 2 represents a bonding site with an adjacent atom.

In general formula (4), R ⁹ and R ¹⁰ each independently represent the same atom or substituent as R ¹ to R ⁵ in general formula (2), but at least one of them is alkyl having 1 or more carbon atoms. It is a group. * 3 represents a bonding site with an adjacent atom. In R ¹ to R ¹⁰ in the general formulas (2) to (4), adjacent groups may be bonded to each other to form a substituted or unsubstituted aliphatic ring. The aromatic ring is not condensed.

R ¹ to R ^{5 in} the general formula (2), R ⁶ to R ⁸ in the general formula (3), and R ⁹ and R ¹⁰ in the general formula (4) are specifically hydrogen atom, deuterium atom , Halogen atoms (eg fluorine atom, chlorine atom, bromine atom etc.), cyano group, nitro group, hydroxy group, mercapto group, alkyl group (eg methyl group, ethyl group, propyl group, isopropyl group, tert-butyl group) Pentyl group, hexyl group, octyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, etc.), cycloalkyl group (for example, cyclopentyl group, cyclohexyl group, etc.), alkenyl group (for example, vinyl group, allyl group, etc.) , Alkynyl groups (eg ethynyl group, propargyl group etc.), heterocyclic groups (eg pyrrolidyl group, imidazolidyl group, morpho Aryl group, oxazolidyl group, etc.), alkoxy group (eg, methoxy group, ethoxy group, propyloxy group, pentyloxy group, hexyloxy group, octyloxy group, dodecyloxy group, etc.), cycloalkoxy group (eg, cyclopentyloxy group) Cyclohexyloxy group etc.), aryloxy group (eg phenoxy group, naphthyloxy group etc.), alkylthio group (eg methylthio group, ethylthio group, propylthio group, pentylthio group, hexylthio group, octylthio group, dodecylthio group etc.), A cycloalkylthio group (eg, cyclopentylthio group, cyclohexylthio group, etc.), an arylthio group (eg, phenylthio group, naphthylthio group, etc.), an alkoxycarbonyl group (eg, methyloxycarbonyl group, ethyloxycarbonyl) Butyloxycarbonyl group, octyloxycarbonyl group, dodecyloxycarbonyl group, etc.), aryloxycarbonyl group (eg, phenyloxycarbonyl group, naphthyloxycarbonyl group, etc.), sulfamoyl group (eg, aminosulfonyl group, methylaminosulfonyl group) Dimethylaminosulfonyl group, butylaminosulfonyl group, hexylaminosulfonyl group, cyclohexylaminosulfonyl group, octylaminosulfonyl group, dodecylaminosulfonyl group, phenylaminosulfonyl group, naphthylaminosulfonyl group, 2-pyridylaminosulfonyl group), acyl A group (for example, acetyl group, ethylcarbonyl group, propylcarbonyl group, pentylcarbonyl group, cyclohexylcarbonyl group, octylcarbonyl group, -Ethylhexylcarbonyl group, dodecylcarbonyl group, phenylcarbonyl group, naphthylcarbonyl group, pyridylcarbonyl group, etc.), acyloxy group (for example, acetyloxy group, ethylcarbonyloxy group, butylcarbonyloxy group, octylcarbonyloxy group, dodecylcarbonyloxy group) Group, phenylcarbonyloxy group, etc.), amide group (for example, methylcarbonylamino group, ethylcarbonylamino group, dimethylcarbonylamino group, propylcarbonylamino group, pentylcarbonylamino group, cyclohexylcarbonylamino group, 2-ethylhexylcarbonylamino group) Octylcarbonylamino group, dodecylcarbonylamino group, phenylcarbonylamino group, naphthylcarbonylamino group, etc.), carbamoyl group (eg For example, aminocarbonyl group, methylaminocarbonyl group, dimethylaminocarbonyl group, propylaminocarbonyl group, pentylaminocarbonyl group, cyclohexylaminocarbonyl group, octylaminocarbonyl group, 2-ethylhexylaminocarbonyl group, dodecylaminocarbonyl group, phenylamino Carbonyl group, naphthylaminocarbonyl group, 2-pyridylaminocarbonyl group, etc.), ureido group (for example, methylureido group, ethylureido group, pentylureido group, cyclohexylureido group, octylureido group, dodecylureido group, phenylureido group, naphthylureido) Group, 2-pyridylaminoureido group, etc.), sulfinyl group (for example, methylsulfinyl group, ethylsulfinyl group, butylsulfinyl group, cyclohexane) Silsulfinyl group, 2-ethylhexylsulfinyl group, dodecylsulfinyl group, phenylsulfinyl group, naphthylsulfinyl group, 2-pyridylsulfinyl group, etc.), alkylsulfonyl group (for example, methylsulfonyl group, ethylsulfonyl group, butylsulfonyl group, cyclohexylsulfonyl) Group, 2-ethylhexylsulfonyl group, dodecylsulfonyl group, etc.), arylsulfonyl group or heteroarylsulfonyl group (eg, phenylsulfonyl group, naphthylsulfonyl group, 2-pyridylsulfonyl group, etc.), amino group (eg, amino group, ethyl group) Amino group, dimethylamino group, butylamino group, cyclopentylamino group, 2-ethylhexylamino group, dodecylamino group, anilino group, naphthylamino group, 2-pyridylamino , Piperidyl groups (also called piperidinyl groups), 2,2,6,6-tetramethylpiperidinyl groups, etc.), fluorinated hydrocarbon groups (for example, fluoromethyl group, trifluoromethyl group, pentafluoroethyl group, penta Fluorophenyl group, etc.), triarylsilyl group (eg, triphenylsilyl group, tri (4-methylphenyl) silyl group, tri (3,5-dimethylphenyl) silyl group, etc.), diarylalkylsilyl group (eg, t -Butyldiphenylsilyl group, isopropyldiphenylsilyl group, etc.), aryldialkylsilyl groups (eg, dimethylphenylsilyl group, isopropyldi (4-methylphenyl) silyl group, etc.), trialkylsilyl groups (eg, trimethylsilyl group, triisopropyl) Silyl group, t-butyldimethylsilyl group, etc.), Examples thereof include a phosphoric ester group (for example, dihexyl phosphoryl group), a phosphite group (for example, diphenylphosphinyl group), a phosphono group, and the like.

Examples of the alkyl group having 1 or more carbon atoms in the general formula (3) or (4) include methyl group, ethyl group, propyl group, isopropyl group, tert-butyl group, pentyl group, hexyl group, octyl group, dodecyl group, tridecyl group. Group, tetradecyl group, pentadecyl group and the like.

In the general formulas (3) and (4), “adjacent atom” in the description of the formula is a carbon atom constituting the phenyl group to which R ¹ and R ⁵ are bonded in the general formula (2).

It is preferable that at least one of R ¹ and R ⁵ in the general formula (2) is represented by the general formula (3).
Further, ^{R 1} and ^{R 5} in the general formula (2), respectively is represented by the general formula (3) or (4), and preferably has a different structure.

Further, the fluorescent compound having the structure represented by the general formula (1) preferably has a structure represented by the following general formula (1a).

In general formula (1a), X represents a π-conjugated condensed ring having a 14π-electron system or more. Y represents a deuterium atom, a triarylsilyl group, a diarylalkylsilyl group, an aryldialkylsilyl group, a trialkylsilyl group, a phenyl group, or a group having a structure represented by the following general formula (2a). Furthermore, you may have a substituent. At least one of Y is a group having a structure represented by the following general formula (2a). When there are a plurality of Ys, they may be the same as or different from each other. n represents the number of Ys that can be substituted for the hydrogen atom on the π-conjugated condensed ring, and represents an integer from 1 to the maximum number.

In general formula (2a), R ¹ to R ⁵ each independently represent the same atom or substituent as R ¹ to R ⁵ in general formula (2), but at least one of R ¹ and R ⁵ is carbon. It is a linear, branched or cyclic alkyl group having two or more, or at least one of R ¹ and R ² and R ⁴ and R ⁵ is bonded to each other to form a substituted or unsubstituted aliphatic ring. At this time, the aromatic ring is not further condensed to the formed aliphatic ring.

X in the general formula (1a) has the same meaning as X in the general formula (1).

In the general formulas (33) to (52), all Rs are groups having a structure represented by the general formula (2a), or one of R is a triarylsilyl group, and the other R Are all groups having a structure represented by the general formula (2a).

The group having a structure represented by the general formula (2a) preferably has a structure represented by the following general formula (2a-1) or (2a-2), and is represented by the general formula (2a-3). It is more preferable to have a structure.

In general formula (2a-1), ring Z3 represents a substituted or unsubstituted aliphatic ring, but an aromatic ring is not further condensed to the aliphatic ring. C ¹ represents a carbon atom. R ¹⁶ and R ¹⁷ each independently represent the same atom or substituent as R ¹ to R ⁵ in formula (2), but at least one of R ¹⁶ and R ¹⁷ is an alkyl group having 1 or more carbon atoms Represents. R ¹⁸ represents a substituent. a represents the number of R ¹⁸ that can be substituted for a hydrogen atom on the ring Z3, and represents an integer from 0 to the maximum number. * 1 represents a binding site with X.

In general formula (2a-2), ring Z3 and ring Z4 represent a substituted or unsubstituted aliphatic ring, but an aromatic ring is not further condensed to the aliphatic ring. C ¹ and ^{C 2} represent the carbon atoms. R ¹⁶ and R ¹⁷ each independently represent the same atom or substituent as R ¹ to R ⁵ in formula (2), but at least one of R ¹⁶ and R ¹⁷ is an alkyl group having 1 or more carbon atoms Represents. R ²¹ and R ²² each independently represent the same atom or substituent as R ¹ to R ⁵ in formula (2), but at least one of R ²¹ and R ²² is an alkyl group having 1 or more carbon atoms Represents. R ¹⁸ and R ²³ each independently represents a substituent. a represents the number of R ¹⁸ that can be substituted for a hydrogen atom on the ring Z3, and represents an integer from 0 to the maximum number. b represents the number of R ²³ that can be substituted in place of the hydrogen atom on the ring Z4, and represents an integer from 0 to the maximum number. * 1 represents a binding site with X.

In general formula (2a-3), C ¹ and C ² represent a carbon atom. R ¹⁶ and R ¹⁷ each independently represent the same atom or substituent as R ¹ to R ⁵ in formula (2), but at least one of R ¹⁶ and R ¹⁷ is an alkyl group having 1 or more carbon atoms Represents. R ²¹ and R ²² each independently represent the same atom or substituent as R ¹ to R ⁵ in formula (2), but at least one of R ²¹ and R ²² is an alkyl group having 1 or more carbon atoms Represents. R ¹⁸ to R ²⁰ and R ²³ to R ²⁵ each independently represent a substituent. c and d each represents an integer of 0-2. * 1 represents a binding site with X.

In the general formulas (2a-1) to (2a-3), the substituents represented by R ¹⁸ to R ²⁰ and R ²³ to R ^{25 have} ring Z1 and ring Z2 in the general formula (DP) described later. And the same substituents that may be used.

Examples compounds of the fluorescent compound of the present invention are shown below, but are not limited thereto.

The fluorescent compound of the present invention can be synthesized by a known method, and an example thereof is shown below.

<Synthesis of Exemplified Compound 6>
Perylenetetraboronic acid pinacol ester (3.0 g), triisopropylbromobenzene (6.1 g), and potassium phosphate (13 g) were taken in a reaction vessel, and the system was purged with nitrogen. After addition of toluene (150 mL) and water (10 mL), palladium acetate (Pd (OAc) ₂ , 0.18 g) and 2-dicyclohexylphosphino-2 ′, 6′-dimethoxy-1,1′-biphenyl (S phos, 1.3 g) was added and stirred for 4 hours under reflux. The reaction mixture was allowed to cool, followed by extraction with toluene and washing with saturated brine. The crude product was purified by column chromatography to give Exemplary Compound 6 (1.16 g, yield: 28%).
About the obtained product, ESI-MS was measured and it identified that it was the exemplary compound 6 (molecular weight: 1061.7, detected value: 1062).

<Synthesis of Exemplary Compound 34>
(Synthesis of Intermediate 1)
[Ir (OMe) (cod)] ₂ (cod = 1,5-cyclooctadiene, 0.15 g), 4,4′-di-tert-butyl-2,2′- under a nitrogen atmosphere in a reaction vessel. Bipyridyl (dtbpy, 0.12 g) was taken and tetrahydrofuran (THF, 100 mL) was added. Subsequently, pinacol borane (B ₂ (pin) ₂ , 1.5 g) was added and stirred at 40 ° C. Subsequently, Chem. Commun. 52, 1124, 2016, and planarized 9-phenylanthracene (1.0 g) synthesized with reference to 2016 was added, and the mixture was stirred at 60 ° C. for 8 hours. After allowing to cool, purification was performed by gel permeation chromatography to obtain Intermediate 1 (1.4 g, yield: 63%).

(Synthesis of Intermediate 2)
Intermediate 1 (1.4 g), triisopropylbromobenzene (2.1 g), and potassium phosphate (3.6 g) were taken in a reaction vessel, and the system was purged with nitrogen. After adding toluene (30 mL) and water (3 mL), palladium acetate (Pd (OAc) ₂ , 0.13 g) and 2-dicyclohexylphosphino-2 ′, 6′-dimethoxy-1,1′-biphenyl (S phos, 0.46 g) was added and stirred for 4 hours under reflux with heating. The reaction mixture was allowed to cool, followed by extraction with toluene and washing with saturated brine. The crude product was purified by column chromatography to obtain Intermediate 2 (0.81 g, yield: 46%).

(Synthesis of Intermediate 3)
Intermediate 2 (0.81 g) was taken in a reaction vessel, and dichloromethane (30 mL) was added and dissolved. Subsequently, N-bromosuccinimide (NBS, 0.31 g) was added, and the mixture was stirred at room temperature (25 ° C.) for 2 hours. After completion of the reaction, water was added and stirred, followed by extraction with dichloromethane and washing with saturated brine. The crude product was purified by column chromatography to obtain Intermediate 3 (0.81 g, yield: 92%).

(Synthesis of Exemplary Compound 34)
Intermediate 3 (0.81 g), phenylboronic acid (0.20 g) and potassium carbonate (0.33 g) were taken in a reaction vessel, and the inside of the system was purged with nitrogen. After adding toluene (20 mL) and water (2 mL), tetrakistriphenylphosphine palladium (Pd (PPh ₃ ) ₄ , 0.085 g) was added, and the mixture was stirred for 4 hours under heating reflux. The reaction mixture was allowed to cool, followed by extraction with toluene and washing with saturated brine. The crude product was purified by column chromatography to obtain Exemplified Compound 34 (0.63 g, yield: 78%).
About the obtained product, ESI-MS was measured and it identified that it was the exemplary compound 34 (molecular weight: 1017.6, detected value: 1018).

<Light emitting material>
The fluorescent compound of the present invention can emit fluorescence by electric field excitation or the like. Therefore, it can be used as various luminescent materials. In addition to the π-conjugated compound, the light emitting material may contain other components as necessary. Further, the light emitting material may be used in a powder form or may be used after being processed into a desired shape. The light emitting material can be applied to, for example, a material for forming a light emitting film described later, a fluorescent paint, and a bioimaging fluorescent dye.

<< Organic material composition >>
The organic material composition of the present invention contains a fluorescent compound having a structure represented by the above general formula (1), and a phosphorescent compound or a thermally activated delayed fluorescent compound, To do. The organic material composition may further contain a host compound.

<Phosphorescent compound>
The phosphorescent compound according to the present invention is a compound containing a heavy atom and capable of emitting light from triplet excitation, and is not particularly limited as long as light emission from triplet excitation is observed.
A phosphorescent compound having a structure represented by the following general formula (DP) is preferable. By using the phosphorescent compound, not only excitons can be stabilized, but also the emission spectrum of the phosphorescent compound and the absorption spectrum of the fluorescent compound having the structure represented by the general formula (1) As a result, excitons can be used for light emission more effectively, and as a result, the lifetime of the element can be extended.

In general formula (DP), M represents Ir or Pt. A ¹ , A ² , B ¹ and B ² each independently represent a carbon atom or a nitrogen atom. Ring Z1 is a substituted or unsubstituted 6-membered aromatic hydrocarbon ring, substituted or unsubstituted 5-membered or 6-membered aromatic heterocycle formed together with A ¹ and A ² , or these rings An aromatic condensed ring containing at least one of Ring Z2 is formed with B ¹ and B ^2, it represents an aromatic condensed ring containing at least one of a substituted or unsubstituted 5- or 6-membered aromatic heterocyclic ring, or the rings. A carbene carbon atom may be sufficient as the carbon atom which the ring Z1 and the ring Z2 have. ^One of the bond between A ¹ and M and the bond between B ¹ and M is a coordination bond, and the other represents a covalent bond. At this time, a condensed ring structure may be formed by bonding substituents of the ring Z1 and the ring Z2. In addition, the ligands represented by two or three rings Z1 and Z2 may be linked to each other directly or via a linker moiety (linking group) in ring Z1 or ring Z2. L represents a monoanionic bidentate ligand coordinated to M, and may have a substituent. m represents an integer of 0-2. n represents an integer of 1 to 3. M + n is 3 when M is Ir, and m + n is 2 when M is Pt. When m or n is 2 or more, the ligands represented by the plurality of rings Z1 and the ring Z2 or the plurality of Ls may be the same as or different from each other. The ligand represented by ring Z1 and ring Z2 and L may be linked.

Examples of the substituent that the ring Z1 and the ring Z2 may have include an alkyl group (for example, methyl group, ethyl group, propyl group, isopropyl group, tert-butyl group, pentyl group, hexyl group, octyl group, dodecyl group). , Tridecyl group, tetradecyl group, pentadecyl group etc.), cycloalkyl group (eg cyclopentyl group, cyclohexyl group etc.), alkenyl group (eg vinyl group, allyl group etc.), alkynyl group (eg ethynyl group, propargyl group etc.) ), Aromatic hydrocarbon group (also called aromatic carbocyclic group, aryl group, etc., for example, phenyl group, p-chlorophenyl group, mesityl group, tolyl group, xylyl group, naphthyl group, anthryl group, azulenyl group, acenaphthenyl group , Fluorenyl group, phenanthryl group, indenyl group, pyrenyl group, biphenylyl Etc.), an aromatic heterocyclic group (for example, furyl group, thienyl group, pyridyl group, pyridazinyl group, pyrimidinyl group, pyrazinyl group, triazinyl group, imidazolyl group, pyrazolyl group, thiazolyl group, quinazolinyl group, carbazolyl group, carbolinyl group, A diazacarbazolyl group (in which one of carbon atoms constituting a carboline ring of a carbolinyl group is replaced by a nitrogen atom), a phthalazinyl group, etc.), a heterocyclic group (for example, a pyrrolidyl group, an imidazolidyl group, Morpholyl group, oxazolidyl group, etc.), alkoxy group (eg, methoxy group, ethoxy group, propyloxy group, pentyloxy group, hexyloxy group, octyloxy group, dodecyloxy group, etc.), cycloalkoxy group (eg, cyclopentyloxy group) Cyclohexyloxy group), Reeloxy group (for example, phenoxy group, naphthyloxy group, etc.), alkylthio group (for example, methylthio group, ethylthio group, propylthio group, pentylthio group, hexylthio group, octylthio group, dodecylthio group, etc.), cycloalkylthio group (for example, cyclopentyl group) Thio group, cyclohexylthio group, etc.), arylthio group (eg, phenylthio group, naphthylthio group, etc.), alkoxycarbonyl group (eg, methyloxycarbonyl group, ethyloxycarbonyl group, butyloxycarbonyl group, octyloxycarbonyl group, dodecyloxy group) Carbonyl group etc.), aryloxycarbonyl group (eg phenyloxycarbonyl group, naphthyloxycarbonyl group etc.), sulfamoyl group (eg aminosulfonyl group, methylaminosulfonate) Group, dimethylaminosulfonyl group, butylaminosulfonyl group, hexylaminosulfonyl group, cyclohexylaminosulfonyl group, octylaminosulfonyl group, dodecylaminosulfonyl group, phenylaminosulfonyl group, naphthylaminosulfonyl group, 2-pyridylaminosulfonyl group, etc.) An acyl group (for example, acetyl group, ethylcarbonyl group, propylcarbonyl group, pentylcarbonyl group, cyclohexylcarbonyl group, octylcarbonyl group, 2-ethylhexylcarbonyl group, dodecylcarbonyl group, phenylcarbonyl group, naphthylcarbonyl group, pyridylcarbonyl group) Etc.), acyloxy groups (for example, acetyloxy group, ethylcarbonyloxy group, butylcarbonyloxy group, octylcarbonyloxy group, dodecyl) Carbonyloxy group, phenylcarbonyloxy group, etc.), amide group (for example, methylcarbonylamino group, ethylcarbonylamino group, dimethylcarbonylamino group, propylcarbonylamino group, pentylcarbonylamino group, cyclohexylcarbonylamino group, 2-ethylhexylcarbonyl) Amino group, octylcarbonylamino group, dodecylcarbonylamino group, phenylcarbonylamino group, naphthylcarbonylamino group, etc.), carbamoyl group (for example, aminocarbonyl group, methylaminocarbonyl group, dimethylaminocarbonyl group, propylaminocarbonyl group, pentyl) Aminocarbonyl group, cyclohexylaminocarbonyl group, octylaminocarbonyl group, 2-ethylhexylaminocarbonyl group, dodecylaminocarbonyl Bonyl group, phenylaminocarbonyl group, naphthylaminocarbonyl group, 2-pyridylaminocarbonyl group, etc.), ureido group (for example, methylureido group, ethylureido group, pentylureido group, cyclohexylureido group, octylureido group, dodecylureido group, Phenylureido group, naphthylureido group, 2-pyridylaminoureido group, etc.), sulfinyl group (for example, methylsulfinyl group, ethylsulfinyl group, butylsulfinyl group, cyclohexylsulfinyl group, 2-ethylhexylsulfinyl group, dodecylsulfinyl group, phenylsulfinyl group, Naphthylsulfinyl group, 2-pyridylsulfinyl group, etc.), alkylsulfonyl group (for example, methylsulfonyl group, ethylsulfonyl group, butylsulfonyl group, Chlorohexylsulfonyl group, 2-ethylhexylsulfonyl group, dodecylsulfonyl group, etc.), arylsulfonyl group or heteroarylsulfonyl group (eg, phenylsulfonyl group, naphthylsulfonyl group, 2-pyridylsulfonyl group, etc.), amino group (eg, amino Group, ethylamino group, dimethylamino group, butylamino group, cyclopentylamino group, 2-ethylhexylamino group, dodecylamino group, anilino group, naphthylamino group, 2-pyridylamino group, piperidyl group (also called piperidinyl group), 2 , 2,6,6-tetramethylpiperidinyl group, etc.), halogen atom (eg, fluorine atom, chlorine atom, bromine atom, etc.), fluorinated hydrocarbon group (eg, fluoromethyl group, trifluoromethyl group, penta) Fluoroethyl group, pentafluor Phenyl group, etc.), cyano group, nitro group, hydroxy group, mercapto group, silyl group (eg, trimethylsilyl group, triisopropylsilyl group, triphenylsilyl group, phenyldiethylsilyl group, etc.), phosphate ester group (eg, dihexyl) Phosphoryl group, etc.), phosphite group (for example, diphenylphosphinyl group, etc.), phosphono group and the like.

Examples of the substituent that L may have include the same substituents that the ring Z1 and ring Z2 may have.

Ring Z2 is preferably a 5-membered aromatic heterocyclic ring, and at least one of B ¹ and B ² is preferably a nitrogen atom.

The phosphorescent compound having a structure represented by the general formula (DP) preferably has a structure represented by the following general formula (DP-1).

In general formula (DP-1), M, A ¹ , A ² , B ¹ , B ² , rings Z1, L, m, and n are M, A ¹ , A ² , B ¹ , B ^2, ring Z1, L, the same meaning as m and n.

B ³ to B ⁵ are an atomic group forming an aromatic heterocyclic ring, and each independently represents a carbon atom, nitrogen atom, oxygen atom or sulfur atom which may have a substituent.
Examples of the substituent that B ³ to B ⁵ may have include the same groups as the substituents that the ring Z1 and ring Z2 in the general formula (DP) may have.

The aromatic heterocycle formed by B ¹ to B ⁵ in the general formula (DP-1) is represented by any of the following general formulas (DP-1a), (DP-1b) and (DP-1c) It preferably has a structure.

In the general formulas (DP-1a), (DP-1b), and (DP-1c), * 4 represents a binding site with A ² in the general formula (DP-1). * 5 represents a binding site with M.
Rb ³ to Rb ⁵ represent a hydrogen atom or a substituent. Examples of the substituent represented by Rb ³ to Rb ⁵ include the same groups as the substituents that the ring Z1 and the ring Z2 in the general formula (DP) may have.
B ⁴ and B ⁵ in the general formula (DP-1a) represent a carbon atom or a nitrogen atom. B ⁴ and B ⁵ are preferably at least one carbon atom.
B ³ to B ⁵ in the general formula (DP-1b) represent a carbon atom or a nitrogen atom. At least one of B ³ to B ⁵ is preferably a carbon atom.
B ³ and B ⁴ in the general formula (DP-1c) represent a carbon atom or a nitrogen atom. B ³ and B ⁴ are preferably at least one carbon atom.

Rb ³ and Rb ⁴ in the general formulas (DP-1a), (DP-1b) and (DP-1c) are preferably further bonded to each other to form a condensed ring structure. The condensed ring structure is more preferably an aromatic ring, and the aromatic ring is more preferably any of a benzimidazole ring, an imidazopyridine ring, an imidazopyrazine ring, or a purine ring.
Rb ⁵ is preferably an alkyl group or an aryl group, and more preferably a phenyl group.

Hereinafter, exemplary compounds of the phosphorescent compound having a structure represented by the general formula (DP) are shown, but not limited thereto.

In addition, the phosphorescent compound that can be used in the present invention can be appropriately selected from, for example, known compounds used in the light emitting layer of the organic EL element.

Known phosphorescent compounds that can be used in the present invention include, but are not limited to, compounds described in the following documents.
Nature 395, 151 (1998), Appl. Phys. Lett. 78, 1622 (2001), Adv. Mater. 19, 739 (2007), Chem. Mater. 17, 3532 (2005), Adv. Mater. 17, 1059 (2005), International Publication No. 2009/100991, International Publication No. 2008/101842, International Publication No. 2003/040257, US Patent Application Publication No. 2006/835469, US Patent Application Publication No. 2006 /. No. 0202194, U.S. Patent Application Publication No. 2007/0087321, U.S. Patent Application Publication No. 2005/0244673, Inorg. Chem. 40, 1704 (2001), Chem. Mater. 16, 2480 (2004), Adv. Mater. 16, 2003 (2004), Angew. Chem. lnt. Ed. 2006, 45, 7800, Appl. Phys. Lett. 86, 153505 (2005), Chem. Lett. 34, 592 (2005), Chem. Commun. 2906 (2005), Inorg. Chem. 42, 1248 (2003), International Publication No. 2009/050290, International Publication No. 2002/015645, International Publication No. 2009/000673, US Patent Application Publication No. 2002/0034656, and US Pat. No. 7,332,232. US Patent Application Publication No. 2009/0108737, US Patent Application Publication No. 2009/0039776, US Patent No. 6921915, US Patent No. 6,687,266, US Patent Application Publication No. 2007/0190359. Specification, US Patent Application Publication No. 2006/0008670, US Patent Application Publication No. 2009/0165846, US Patent Application Publication No. 2008/0015355, US Patent No. 7250226, US Patent No. No. 7396598 , U.S. Patent Application Publication No. 2006/0263635, U.S. Patent Application Publication No. 2003/0138657, U.S. Patent Application Publication No. 2003/0152802, U.S. Patent No. 7090928, Angew. Chem. lnt. Ed. 47, 1 (2008), Chem. Mater. 18, 5119 (2006), Inorg. Chem. 46, 4308 (2007), Organometallics 23, 3745 (2004), Appl. Phys. Lett. 74, 1361 (1999), International Publication No. 2002/002714, International Publication No. 2006/009024, International Publication No. 2006/056418, International Publication No. 2005/019373, International Publication No. 2005/123873, International Publication No. 2005/123873, International Publication No. 2007/004380, International Publication No. 2006/082742, US Patent Application Publication No. 2006/0251923, US Patent Application Publication No. 2005/0260441, US Pat. No. 7,393,599. Description, US Pat. No. 7,534,505, US Pat. No. 7,445,855, US Patent Application Publication No. 2007/0190359, US Patent Application Publication No. 2008/0297033, US Pat. No. 7,338,722 , US special Published Patent Application No. 2002/0134984, U.S. Pat. No. 7,279,704, U.S. Patent Application Publication No. 2006/098120, U.S. Patent Application Publication No. 2006/103874, International Publication No. 2005/076380, International Publication No. 2010/032663, International Publication No. 2008/140115, International Publication No. 2007/052431, International Publication No. 2011/134013, International Publication No. 2011/157339, International Publication No. 2010/086089, International Publication 2009/113646, International Publication No. 2012/020327, International Publication No. 2011/051404, International Publication No. 2011/004639, International Publication No. 2011/073149, US Patent Application Publication No. 2012/228583, USA No. 2012/212126, JP 2012-069737, JP 2012-195554, JP 2009-114086, JP 2003-81988, JP 2002-302671. JP 2002-363552 A, etc.
Further, when the carbon atoms of the ring Z1 and the ring Z2 are carbene carbon atoms (specifically, when they are carbene complexes), for example, International Publication No. 2005/019373, International Publication No. 2006/056418, Carbene complexes described in International Publication No. 2005/113704, International Publication No. 2007/115970, International Publication No. 2007/115981 and International Publication No. 2008/000727 can be suitably used.

<Heat-activated delayed fluorescent compound>
The thermally activated delayed fluorescent compound according to the present invention utilizes a phenomenon in which reverse intersystem crossing from triplet excitons to singlet excitons (hereinafter simply referred to as “RISC”) occurs. There is no particular limitation as long as fluorescence emission utilizing a phenomenon (thermally activated delayed fluorescence (hereinafter also referred to as “TADF” as appropriate)) is observed (thermally activated delayed fluorescence (also referred to as “thermally activated delayed fluorescence”)).

Examples of the thermally activated delayed fluorescent compound are shown below, but are not limited thereto.

In addition, as the thermally activated delayed fluorescent compound that can be used in the present invention, for example, it can be appropriately selected from known compounds used for the light emitting layer of the organic EL device.

Examples of known thermally activated delayed fluorescent compounds that can be used in the present invention include, but are not limited to, compounds described in the following documents.
JP 2013-116975 A, Nature, 2012, 492, 234, Nature, Photonics, 2014, 8, 326, Adv. Mater. The thermally activated delayed fluorescent compound described in 2014, 26, 7931 can be preferably used.

<Host compound>
The organic material composition of the present invention may contain a host compound in addition to the fluorescent compound, the phosphorescent compound, or the thermally activated delayed fluorescent compound.
The host compound according to the present invention is described below.

As the host compound, known host compounds may be used alone or in combination. By using a plurality of types of host compounds, for example, when an organic material composition is applied to an organic EL element or the like, it is possible to adjust the movement of charges, and high efficiency can be realized.

The host compound according to the present invention is not particularly limited, and for example, a compound conventionally used in an organic EL device can be used. It may be a low molecular compound or a high molecular compound having a repeating unit, or a compound having a reactive group such as a vinyl group or an epoxy group.

The host compound according to the present invention is preferably a compound having a structure represented by the following general formula (HA) or (HB).

In the general formulas (HA) and (HB), Xa represents O or S. Xb, Xc, Xd and Xe each independently represent a hydrogen atom, a substituent or a group having a structure represented by the following general formula (HC), and at least one of Xb, Xc, Xd and Xe is A group having a structure represented by the following general formula (HC) is represented, and at least one of the groups having a structure represented by the following general formula (HC) is a carbazolyl group.

General formula (HC)
Ar- (L ′) n- *

In general formula (HC), L ′ represents a divalent linking group derived from an aromatic hydrocarbon ring or an aromatic heterocyclic ring. n represents an integer of 0 to 3, and when n is 2 or more, a plurality of L ′ may be the same or different. * Represents a binding site with the general formula (HA) or (HB). Ar represents a group having a structure represented by the following general formula (HD).

In the general formula (HD), Xf represents N (R ′), O or S. E ₁ to E _{8 each} represent C (R ″) or N, and R ′ and R ″ each represent a hydrogen atom, a substituent, or a bonding site with L ′ in the general formula (HC). * Represents a binding site with L ′ in the general formula (HC).

In the compound having the structure represented by the general formula (HA), preferably at least two of Xb, Xc, Xd and Xe are represented by the general formula (HC), and more preferably Xc is represented by the general formula (HC). And Ar in the general formula (HC) represents a carbazolyl group which may have a substituent.

Examples of the substituents represented by Xb, Xc, Xd and Xe in the general formulas (HA) and (HB) and the substituents represented by R ′ and R ″ in the general formula (HD) include the above general formula (DP ) And the same substituents that the ring Z1 and ring Z2 may have.

Examples of the aromatic hydrocarbon ring represented by L ′ in the general formula (HC) include a benzene ring, a p-chlorobenzene ring, a mesitylene ring, a toluene ring, a xylene ring, a naphthalene ring, an anthracene ring, an azulene ring, and an acenaphthene ring. Fluorene ring, phenanthrene ring, indene ring, pyrene ring, biphenyl ring and the like.
Examples of the aromatic heterocycle represented by L ′ in the general formula (HC) include a furan ring, a thiophene ring, a pyridine ring, a pyridazine ring, a pyrimidine ring, a pyrazine ring, a triazole ring, an imidazole ring, a pyrazole ring, and a thiazole ring. Quinazoline ring, carbazole ring, carboline ring, diazacarbazole ring (in which one of carbon atoms constituting the carboline ring is replaced by a nitrogen atom), a phthalazine ring, and the like.

Specific examples of the host compound according to the present invention include compounds applicable to the present invention in addition to the compound having the structure represented by the general formula (HA) or (HB). It is not specifically limited to.

In addition, specific examples of known host compounds used in the organic material composition of the present invention include compounds described in the following documents, but the present invention is not limited thereto.

JP-A-2001-257076, 2002-308855, 2001-313179, 2002-319491, 2001-357777, 2002-334786, 2002-8860, 2002-334787, 2002-15871, 2002-334788, 2002-43056, 2002-334789, 2002-75645, 2002-338579, 2002-105445, 2002-343568, 2002-141173, 2002-352957, 2002-203683, 2002-363227, 2002-231453, 2003-3165, 2002-234888, 2003-27048, 2002-255934, 2002-260861, 2002-280183, 2002-299060, 2002 -302516, 2002-305083, 2002-305084, 2002-308837, U.S. Patent Application Publication No. 2003/0175553, U.S. Patent Application Publication No. 2006/0280965, US Patent Application Publication No. 2005/0112407, US Patent Application Publication No. 2009/0017330, US Patent Application Publication No. 2009/0030202, US Patent Application Publication No. 2005/0238919, International Publication 2001/039234, International Publication No. 2009/021126, International Publication No. 2008/056746, International Publication No. 2004/093207, International Publication No. 2005/089025, International Publication No. 2007/063796, International Publication No. 2007/2007 / No. 063754, International Publication No. 2004/107822, International Publication No. 2005/030900, International Publication No. 2006/114966, International Publication No. 2009/086028, International Publication No. 2009/003898, International Publication No. 2012/023947 JP-A-2008-074939, JP-A-2007-254297, European Patent No. 2034538, and the like. Furthermore, compounds H-1 to H-230 described in paragraphs [0255] to [0293] of JP-A-2015-38941 can also be suitably used.

The fluorescent light-emitting compound, phosphorescent light-emitting compound, heat-activated delayed fluorescent compound, and host compound contained in the organic material composition of the present invention have been described above, but any phosphorescent light-emitting compound or heat is described. A combination of an activated delayed fluorescent compound and a host compound may also be used.
In addition, the plurality of phosphorescent compounds or thermally activated delayed fluorescent compounds described above may be used in combination, and the plurality of host compounds described above may be used in combination.

<< Organic EL element >>
The fluorescent compound having the structure represented by the general formula (1) of the present invention can be used as an organic EL device material.
The organic EL device of the present invention has an organic functional layer including at least a light emitting layer between an anode and a cathode, and an organic EL device material containing the fluorescent compound of the present invention in any of the organic functional layers is provided. Contained.

<Structure layers of organic EL elements>
As typical element structures in the organic EL element of the present invention, the following structures (1) to (7) may be mentioned, but are not limited thereto.

(1) Anode / light emitting layer / cathode (2) Anode / light emitting layer / electron transport layer / cathode (3) Anode / hole transport layer / light emitting layer / cathode (4) Anode / hole transport layer / light emitting layer / electron Transport layer / cathode (5) anode / hole transport layer / light emitting layer / electron transport layer / electron injection layer / cathode (6) anode / hole injection layer / hole transport layer / light emitting layer / electron transport layer / cathode ( 7) Anode / hole injection layer / hole transport layer / (electron blocking layer /) light emitting layer / (hole blocking layer /) electron transport layer / electron injection layer / cathode

In the above typical element configuration, a layer excluding the anode and the cathode is referred to as an organic functional layer.
Among the above, the configuration (7) is preferably used, but is not limited thereto.

The light emitting layer according to the present invention is composed of a single layer or a plurality of layers. When there are a plurality of light emitting layers, a non-light emitting intermediate layer may be provided between the light emitting layers.
The light emitting layer according to the present invention contains two kinds of light emitting materials having different emission maximum wavelengths, the long wavelength side light emitting material is a phosphorescent compound, and the short wavelength side light emitting material is the fluorescent compound of the present invention. Preferably there is. These two kinds of light emitting materials may be contained in the same layer, or may be contained in a single light emitting layer. The absorption spectrum of the phosphorescent compound and the absorption spectrum of the fluorescent compound may partially overlap.

If necessary, a hole blocking layer (also referred to as a hole blocking layer) or an electron injection layer (also referred to as a cathode buffer layer) may be provided between the light emitting layer and the cathode. An electron blocking layer (also referred to as an electron barrier layer) or a hole injection layer (also referred to as an anode buffer layer) may be provided therebetween.

The electron transport layer is a layer having a function of transporting electrons, and in a broad sense, an electron injection layer and a hole blocking layer are also included in the electron transport layer. Further, the electron transport layer may be composed of a plurality of layers.

The hole transport layer is a layer having a function of transporting holes, and in a broad sense, a hole injection layer and an electron blocking layer are also included in the hole transport layer. The hole transport layer may be composed of a plurality of layers.

(Tandem structure)
The organic EL element of the present invention may be a so-called tandem structure element in which a plurality of light emitting units including at least one light emitting layer are stacked.

Examples of typical element configurations of the tandem structure include the following configurations.

Anode / first light emitting unit / second light emitting unit / third light emitting unit / cathode Anode / first light emitting unit / intermediate layer / second light emitting unit / intermediate layer / third light emitting unit / cathode

Here, the first light emitting unit, the second light emitting unit, and the third light emitting unit may all have the same configuration or may be different. Further, the two light emitting units may be the same, and the remaining one may be different.

In addition, the third light emitting unit may not be provided, while another light emitting unit or an intermediate layer may be provided between the third light emitting unit and the electrode.

The plurality of light emitting units may be directly stacked or may be stacked via an intermediate layer.
The intermediate layer is generally also called an intermediate electrode, intermediate conductive layer, charge generation layer, electron extraction layer, connection layer, or intermediate insulating layer, and electrons are transferred to the anode-side adjacent layer and holes to the cathode-side adjacent layer. A known material structure can be used as long as the layer has a function of supplying.

Examples of materials used for the intermediate layer include ITO (indium tin oxide), IZO (indium zinc oxide), ZnO ₂ , TiN, ZrN, HfN, TiO _x , VO _x , CuI, InN, GaN, Conductive inorganic compound layers such as CuAlO ₂ , CuGaO ₂ , SrCu ₂ O ₂ , LaB ₆ , RuO ₂ , and Al, two-layer films such as Au / Bi ₂ O ₃ , SnO ₂ / Ag / SnO ₂ , ZnO / Ag / ZnO, Bi ₂ O ₃ / Au / Bi ₂ O ₃ , TiO ₂ / TiN / TiO ₂ , TiO ₂ / ZrN / TiO _{2 and} other multilayered films, C _{60 and} other fullerenes, oligothiophene and other conductive materials Examples include organic material layers, conductive organic compound layers such as metal phthalocyanines, metal-free phthalocyanines, metal porphyrins, and metal-free porphyrins. The present invention is not limited thereto.

Examples of a preferable configuration in the light emitting unit include a configuration in which the anode and the cathode are excluded from the configurations (1) to (7) described in the representative element configuration, but the present invention is not limited to these. Not.

Specific examples of the tandem organic EL element include, for example, US Pat. No. 6,337,492, US Pat. No. 7,420,203, US Pat. No. 7,473,923, US Pat. No. 6,872,472, US Pat. No. 6,107,734. Specification, U.S. Pat. No. 6,337,492, International Publication No. 2005/009087, JP-A-2006-228712, JP-A-2006-24791, JP-A-2006-49393, JP-A-2006-49394 JP-A-2006-49396, JP-A-2011-96679, JP-A-2005-340187, JP-A-4711424, JP-A-3496868, JP-A-3848564, JP-A-4421169, No. 2010-192719, Special Elements described in JP2009-076929, JP2008-078414, JP2007-059848, JP2003-272860, JP2003-045676, International Publication No. 2005/094130, etc. Although a structure, a constituent material, etc. are mentioned, this invention is not limited to these.

Hereinafter, each layer constituting the organic EL element of the present invention will be described.

<Light emitting layer>
The light emitting layer according to the present invention provides a field in which electrons and holes injected from an electrode or an adjacent layer (hereinafter also referred to as “adjacent layer”) are recombined to emit light via excitons. The layer that emits light may be within the light emitting layer or at the interface between the light emitting layer and the adjacent layer.

The total thickness of the light emitting layer is not particularly limited, but it prevents the uniformity of the film to be formed, the application of unnecessary high voltage during light emission, and the improvement of the stability of the emission color with respect to the driving current. From the viewpoint, it is preferable to adjust within the range of 2 nm to 5 μm, more preferably within the range of 2 to 500 nm, and even more preferably within the range of 5 to 200 nm.

In the present invention, the thickness of each light emitting layer is preferably adjusted within the range of 2 nm to 1 μm, more preferably adjusted within the range of 2 to 200 nm, and further preferably within the range of 3 to 150 nm. Adjusted in.

(Luminescent dopant, host compound)
The light emitting layer according to the present invention preferably contains a fluorescent compound having a structure represented by the general formula (1), and in addition to the fluorescent compound, a phosphorescent compound and a host compound It is a more preferable aspect that it is comprised.
In addition, the light emitting layer according to the present invention may contain a material of a layer adjacent to the light emitting layer. Examples of the material of the adjacent layer include a hole transport material.

(1) Luminescent dopant As the luminescent dopant, it is preferable to use a phosphorescent compound (also referred to as a phosphorescent dopant or a phosphorescent compound) and a fluorescent compound (fluorescent dopant or fluorescent compound) in combination.

In the present invention, the phosphorescent compound may be used in combination of two or more kinds, or a combination of dopants having different structures may be used. Thereby, arbitrary luminescent colors can be obtained.

The color emitted by the organic EL element of the present invention is shown in FIG. 4.16 on page 108 of “New Color Science Handbook” (edited by the Japan Society of Color Science, University of Tokyo Press, 1985). It is determined by the color when the result measured with Minolta Co., Ltd. is applied to the CIE chromaticity coordinates.

In the present invention, it is also preferable that the light emitting layer of one layer or a plurality of layers contains a plurality of light emitting dopants having different emission colors and emits white light.
There are no particular limitations on the combination of light-emitting dopants that exhibit white, but examples include blue and orange, and a combination of blue, green, and red.

The white color in the organic EL device according to the present invention is not particularly limited, and may be white near orange or white near blue, but when the front luminance at 2 degrees viewing angle is measured by the above method. In addition, the chromaticity in the CIE 1931 color system at 1000 cd / m ² is preferably in the region of x = 0.39 ± 0.09 and y = 0.38 ± 0.08.

(1.1) Phosphorescent compound A phosphorescent compound is a compound in which light emission from triplet excitation is observed, specifically, a compound that emits phosphorescence at room temperature (25 ° C.). The phosphorescence quantum yield is defined as a compound of 0.01 or more at 25 ° C., but the preferred phosphorescence quantum yield is 0.1 or more.

The phosphorescence quantum yield in the present invention can be measured by the method described in Spectra II, page 398 (1992 edition, Maruzen) of the Fourth Edition Experimental Chemistry Course 7. Although the phosphorescence quantum yield in a solution can be measured using various solvents, in the present invention, the phosphorescence emitting compound achieves the above phosphorescence quantum yield (0.01 or more) in any solvent. It only has to be done.

There are two types of light emission principles of phosphorescent compounds. One is the recombination of carriers on the host compound to which carriers are transported, generating an excited state of the host compound, and this energy is phosphorescent. By transferring to a compound, it is an energy transfer type in which light emission from the phosphorescent compound is obtained.
The other is a carrier trap type in which a phosphorescent compound serves as a carrier trap and recombination of carriers occurs on the phosphorescent compound, and light emission from the phosphorescent compound is obtained.
In any case, the condition is that the excited state energy of the phosphorescent compound is lower than the excited state energy of the host compound.

The phosphorescent compound that can be used in the present invention can be appropriately selected from known compounds used for the light emitting layer of the organic EL device. Specifically, a phosphorescent compound having a structure represented by the above general formula (DP), a known phosphorescent compound described in the above-described literature, and the like can be given.
Among these, preferred phosphorescent compounds include organometallic complexes having Ir as a central metal. More preferably, a complex containing at least one coordination mode among metal-carbon bond, metal-nitrogen bond, metal-oxygen bond, and metal-sulfur bond is preferable.

(1.2) Fluorescent Compound The luminescent layer according to the present invention may contain a fluorescent compound having a structure represented by the general formula (1), or other fluorescent emission different from this. An organic compound may be contained, or these may be used in combination.

Other fluorescent compounds are compounds that can emit light from singlet excitation, and are not particularly limited as long as light emission from singlet excitation is observed.

Examples of other fluorescent compounds include anthracene derivatives, pyrene derivatives, chrysene derivatives, fluoranthene derivatives, perylene derivatives, fluorene derivatives, arylacetylene derivatives, styrylarylene derivatives, styrylamine derivatives, arylamine derivatives, boron complexes, coumarin derivatives. , Pyran derivatives, cyanine derivatives, croconium derivatives, squalium derivatives, oxobenzanthracene derivatives, fluorescein derivatives, rhodamine derivatives, pyrylium derivatives, perylene derivatives, polythiophene derivatives, rare earth complex compounds, and the like.

In recent years, fluorescent compounds using delayed fluorescence have been developed, and these may be used.

Specific examples of the fluorescent compound using delayed fluorescence include, for example, compounds described in International Publication No. 2011/156793, Japanese Unexamined Patent Application Publication No. 2011-213743, Japanese Unexamined Patent Application Publication No. 2010-93181, and the like. The present invention is not limited to these.

(2) Host compound The host compound is a compound mainly responsible for charge injection and transport in the light emitting layer, and its own light emission is not substantially observed in the organic EL device.

Preferably, it is a compound having a phosphorescence quantum yield of phosphorescence of less than 0.1 at room temperature (25 ° C.), more preferably a compound having a phosphorescence quantum yield of less than 0.01.

Also, the excited state energy of the host compound is preferably higher than the excited state energy of the light-emitting dopant contained in the same layer.

The host compounds may be used alone or in combination of two or more. By using a plurality of types of host compounds, it is possible to adjust the movement of charges, and the organic EL element can be made highly efficient.

The host compound is not particularly limited, and a compound conventionally used in an organic EL device can be used. It may be a low molecular compound or a high molecular compound having a repeating unit, or a compound having a reactive group such as a vinyl group or an epoxy group.

As a known host compound, while having a hole transporting ability or an electron transporting ability, it is possible to prevent the emission of light from being long-wavelength, and furthermore, the organic EL element is stable against heat generation during driving at a high temperature or during driving of the element. From the viewpoint of operating, it is preferable to have a high glass transition temperature (Tg). Tg is preferably 90 ° C. or higher, more preferably 120 ° C. or higher.
Here, the glass transition point (Tg) is a value obtained by a method based on JIS K 7121 using DSC (Differential Scanning Calorimetry).

Examples of known host compounds used in the organic EL device of the present invention include the same host compounds as those in the organic material composition described above.

The host compound used in the present invention may be used in an adjacent layer adjacent to the light emitting layer.

<Electron transport layer>
The electron transport layer is made of a material having a function of transporting electrons, and only needs to have a function of transmitting electrons injected from the cathode to the light emitting layer.

The total thickness of the electron transport layer is not particularly limited, but is usually in the range of 2 nm to 5 μm, more preferably in the range of 2 to 500 nm, and still more preferably in the range of 5 to 200 nm.

Also, in the organic EL element, when light generated in the light emitting layer is extracted from the electrode, the light extracted directly from the light emitting layer interferes with the light extracted after being reflected by the electrode from which the light is extracted and the electrode located at the counter electrode. It is known to cause. When light is reflected by the cathode, this interference effect can be efficiently utilized by appropriately adjusting the total thickness of the electron transport layer within the range of 5 nm to 1 μm.

On the other hand, when the thickness of the electron transport layer is increased, the voltage is likely to increase. Therefore, particularly when the thickness is large, the electron mobility of the electron transport layer is 1 × 10 ⁻⁵ cm ² / Vs or more. Is preferred.

The material used for the electron transport layer (hereinafter referred to as an electron transport material) may be any of electron injecting or transporting properties and hole blocking properties, and can be selected from conventionally known compounds. Can be selected and used.

For example, nitrogen-containing aromatic heterocyclic derivatives (carbazole derivatives, azacarbazole derivatives (one or more carbon atoms constituting the carbazole ring are substituted with nitrogen atoms), pyridine derivatives, pyrimidine derivatives, pyrazine derivatives, pyridazine derivatives, Triazine derivatives, quinoline derivatives, quinoxaline derivatives, phenanthroline derivatives, azatriphenylene derivatives, oxazole derivatives, thiazole derivatives, oxadiazole derivatives, thiadiazole derivatives, triazole derivatives, benzimidazole derivatives, benzoxazole derivatives, benzthiazole derivatives, etc.), dibenzofuran derivatives, And dibenzothiophene derivatives, silole derivatives, aromatic hydrocarbon ring derivatives (naphthalene derivatives, anthracene derivatives, triphenylene, etc.)

In addition, a metal complex having a quinolinol skeleton or a dibenzoquinolinol skeleton as a ligand, such as tris (8-quinolinol) aluminum (Alq ₃ ), tris (5,7-dichloro-8-quinolinol) aluminum, tris (5,7 -Dibromo-8-quinolinol) aluminum, tris (2-methyl-8-quinolinol) aluminum, tris (5-methyl-8-quinolinol) aluminum, bis (8-quinolinol) zinc (Znq), etc., and metal complexes thereof A metal complex in which the central metal is replaced with In, Mg, Cu, Ca, Sn, Ga, or Pb can also be used as an electron transporting material.

In addition, metal-free or metal phthalocyanine, or those having terminal ends substituted with an alkyl group or a sulfonic acid group can be preferably used as the electron transporting material. Distyrylpyrazine derivatives can also be used as electron transport materials, and inorganic semiconductors such as n-type-Si and n-type-SiC can be used as electron-transport materials as well as hole-injection layers and hole-transport layers. Can do.

Also, a polymer material in which these materials are introduced into a polymer chain or these materials as a polymer main chain can be used.

In the electron transport layer, the electron transport layer may be doped with a doping material as a guest material to form an electron transport layer having a high n property (electron rich). Examples of the doping material include n-type dopants such as metal complexes and metal compounds such as metal halides. Specific examples of the electron transport layer having such a structure include, for example, JP-A-4-297076, JP-A-10-270172, JP-A-2000-196140, 2001-102175, J. Pat. Appl. Phys. , 95, 5773 (2004) and the like.

Specific examples of known preferable electron transport materials used in the organic EL device of the present invention include, but are not limited to, compounds described in the following documents.

US Pat. No. 6,528,187, US Pat. No. 7,230,107, US Patent Application Publication No. 2005/0025993, US Patent Application Publication No. 2004/0036077, US Patent Application Publication No. 2009/0115316 U.S. Patent Application Publication No. 2009/0101870, U.S. Patent Application Publication No. 2009/0179554, International Publication No. 2003/060956, International Publication No. 2008/120855, Appl. Phys. Lett. 75, 4 (1999), Appl. Phys. Lett. 79, 449 (2001), Appl. Phys. Lett. 81, 162 (2002), Appl. Phys. Lett. 81, 162 (2002), Appl. Phys. Lett. 79,156 (2001), U.S. Patent No. 7964293, U.S. Patent Application Publication No. 2009/030202, International Publication No. 2004/080975, International Publication No. 2004/063159, International Publication No. 2005/085387. , International Publication No. 2006/067931, International Publication No. 2007/085652, International Publication No. 2008/114690, International Publication No. 2009/066942, International Publication No. 2009/066779, International Publication No. 2009/054253, International Publication No. Japanese Patent Publication No. 2011-086935, International Publication No. 2010/150593, International Publication No. 2010/047707, European Patent No. 2311826, Japanese Unexamined Patent Publication No. 2010-251675, Japanese Unexamined Patent Publication No. 2009-209133, Japanese Unexamined Patent Publication No. 2009. -1241 No. 4, JP 2008-277810 A, JP 2006-156445 A, JP 2005-340122 A, JP 2003-45662 A, JP 2003-31367 A, JP 2003-282270 A. Gazette, International Publication No. 2012/115034, and the like.

More preferable electron transport materials include pyridine derivatives, pyrimidine derivatives, pyrazine derivatives, triazine derivatives, dibenzofuran derivatives, dibenzothiophene derivatives, carbazole derivatives, azacarbazole derivatives, and benzimidazole derivatives.

The electron transport material may be used alone or in combination of two or more.

<Hole blocking layer>
The hole blocking layer is a layer having a function of an electron transport layer in a broad sense, and is preferably made of a material having a function of transporting electrons and a small ability to transport holes, and transporting electrons while transporting holes. The probability of recombination of electrons and holes can be improved by blocking.

Moreover, the above-described configuration of the electron transport layer can be used as a hole blocking layer according to the present invention, if necessary.

The hole blocking layer is preferably provided adjacent to the cathode side of the light emitting layer.

The thickness of the hole blocking layer is preferably in the range of 3 to 100 nm, and more preferably in the range of 5 to 30 nm.

As the material used for the hole blocking layer, the material used for the electron transport layer is preferably used, and the material used as the host compound is also preferably used for the hole blocking layer.

<Electron injection layer>
An electron injection layer (also referred to as a “cathode buffer layer”) is a layer provided between a cathode and a light emitting layer in order to reduce driving voltage or improve light emission luminance. (November 30, 1998, issued by NTS Corporation) ”, Volume 2, Chapter 2,“ Electrode Materials ”(pages 123 to 166).

In the present invention, the electron injection layer may be provided as necessary, and may be present between the cathode and the light emitting layer or between the cathode and the electron transport layer as described above.

The electron injection layer is preferably a very thin film, and depending on the material, the thickness is preferably in the range of 0.1 to 5 nm. Moreover, the nonuniform film | membrane in which a constituent material exists intermittently may be sufficient.

Details of the electron injection layer are also described in JP-A-6-325871, JP-A-9-17574, JP-A-10-74586, and the like. Specific examples of materials preferably used for the electron injection layer are as follows. , Metals typified by strontium and aluminum, alkali metal compounds typified by lithium fluoride, sodium fluoride, potassium fluoride, etc., alkaline earth metal compounds typified by magnesium fluoride, calcium fluoride, etc., oxidation Examples thereof include metal oxides typified by aluminum, metal complexes typified by lithium 8-hydroxyquinolate (Liq), and the like. Moreover, it is also possible to use said electron transport material.

The materials used for the electron injection layer may be used alone or in combination of two or more.

<Hole transport layer>
The hole transport layer is made of a material having a function of transporting holes, and may have a function of transmitting holes injected from the anode to the light emitting layer.

The total thickness of the hole transport layer is not particularly limited, but is usually in the range of 5 nm to 5 μm, more preferably in the range of 2 to 500 nm, and still more preferably in the range of 5 to 200 nm.

As a material used for the hole transport layer (hereinafter referred to as a hole transport material), any material that has either a hole injection property or a transport property or an electron barrier property may be used. Any one can be selected and used.

For example, porphyrin derivatives, phthalocyanine derivatives, oxazole derivatives, oxadiazole derivatives, triazole derivatives, imidazole derivatives, pyrazoline derivatives, pyrazolone derivatives, phenylenediamine derivatives, hydrazone derivatives, stilbene derivatives, polyarylalkane derivatives, triarylamine derivatives, carbazole derivatives , Indolocarbazole derivatives, isoindole derivatives, acene derivatives such as anthracene and naphthalene, fluorene derivatives, fluorenone derivatives, and polyvinyl carbazole, polymer materials or oligomers with aromatic amines introduced into the main chain or side chain, polysilane, conductive Polymer or oligomer (for example, PEDOT: PSS, aniline copolymer, polyaniline, polythiophene, etc.)

Examples of the triarylamine derivative include a benzidine type typified by α-NPD, a starburst type typified by MTDATA, and a compound having fluorene or anthracene in the triarylamine linking core part.

In addition, hexaazatriphenylene derivatives such as those described in JP-T-2003-519432 and JP-A-2006-135145 can also be used as a hole transport material.

Furthermore, a hole transport layer having a high p property doped with impurities can also be used. Examples thereof include JP-A-4-297076, JP-A-2000-196140, 2001-102175, J.A. Appl. Phys. 95, 5773 (2004), and the like.

JP-A-11-251067, J. Org. Huang et. al. It is also possible to use so-called p-type hole transport materials and inorganic compounds such as p-type-Si and p-type-SiC, as described in the literature (Applied Physics Letters 80 (2002), p. 139). Further, ortho-metalated organometallic complexes having Ir or Pt as a central metal as typified by Ir (ppy) ₃ are also preferably used.

Although the above-mentioned materials can be used as the hole transport material, a triarylamine derivative, a carbazole derivative, an indolocarbazole derivative, an azatriphenylene derivative, an organometallic complex, or an aromatic amine is introduced into the main chain or side chain. The polymer materials or oligomers used are preferably used.

Specific examples of known preferable hole transport materials used in the organic EL device of the present invention include, but are not limited to, the compounds described in the following documents in addition to the documents listed above.

For example, Appl. Phys. Lett. 69, 2160 (1996), J. MoI. Lumin. 72-74,985 (1997), Appl. Phys. Lett. 78, 673 (2001), Appl. Phys. Lett. 90, 183503 (2007), Appl. Phys. Lett. 90, 183503 (2007), Appl. Phys. Lett. 51, 913 (1987), Synth. Met. 87, 171 (1997), Synth. Met. 91, 209 (1997), Synth. Met. 111, 421 (2000), SID Symposium Digest, 37, 923 (2006), J. Am. Mater. Chem. 3,319 (1993), Adv. Mater. 6, 677 (1994), Chem. Mater. 15, 3148 (2003), U.S. Patent Application Publication No. 2003/0162053, U.S. Patent Application Publication No. 2002/0158242, U.S. Patent Application Publication No. 2006/0240279, U.S. Patent Application Publication No. 2008/2008. No. 0220265, US Pat. No. 5,016,569, WO 2007/002683, WO 2009/018009, EP 650955, US Patent Application Publication No. 2008/0124572, US Patent Application Publication No. 2007/0278938, U.S. Patent Application Publication No. 2008/0106190, U.S. Patent Application Publication No. 2008/0018221, International Publication No. 2012/115034, Special Table No. 2003-519432, Special Publication No. Open 2006-135 45 No. is US Patent Application No. 13/585981 Patent like.

The hole transport material may be used alone or in combination of two or more.

<Electron blocking layer>
The electron blocking layer is a layer having a function of a hole transport layer in a broad sense, and is preferably made of a material having a function of transporting holes and a small ability to transport electrons, and transporting electrons while transporting holes. The probability of recombination of electrons and holes can be improved by blocking.

Moreover, the above-described configuration of the hole transport layer can be used as an electron blocking layer as necessary.

The electron blocking layer is preferably provided adjacent to the anode side of the light emitting layer.

The thickness of the electron blocking layer is preferably in the range of 3 to 100 nm, and more preferably in the range of 5 to 30 nm.

As the material used for the electron blocking layer, the material used for the hole transport layer is preferably used, and the material used for the host compound is also preferably used for the electron blocking layer.

<Hole injection layer>
The hole injection layer (also referred to as “anode buffer layer”) is a layer provided between the anode and the light-emitting layer in order to lower the driving voltage and improve the light emission luminance. (November 30, 1998, issued by NTS Corporation) ”, Volume 2, Chapter 2,“ Electrode Materials ”(pages 123-166).

In the present invention, the hole injection layer may be provided as necessary, and may be present between the anode and the light emitting layer or between the anode and the hole transport layer as described above.

The details of the hole injection layer are described in JP-A-9-45479, JP-A-9-260062, JP-A-8-288069, etc. Examples of materials used for the hole injection layer include: And materials used for the hole transport layer.

Among them, phthalocyanine derivatives typified by copper phthalocyanine, hexaazatriphenylene derivatives as described in JP-T-2003-519432, JP-A-2006-135145, etc., metal oxides typified by vanadium oxide, amorphous Conductive polymers such as carbon, polyaniline (emeraldine) and polythiophene, orthometalated complexes represented by tris (2-phenylpyridine) iridium complex, and triarylamine derivatives are preferred.

The materials used for the hole injection layer may be used alone or in combination of two or more.

<Contains>
The organic functional layer according to the present invention may further contain other inclusions.

Examples of the inclusions include halogen elements such as bromine, iodine and chlorine, halogenated compounds, alkali metals such as Pd, Ca, Na, alkaline earth metals, transition metal compounds, complexes, and salts.

The content of the inclusions can be arbitrarily determined, but is preferably 1000 ppm or less, more preferably 500 ppm or less, still more preferably 50 ppm or less with respect to the total mass% of the contained layer. .

However, it is not within this range depending on the purpose of improving the transportability of electrons and holes or the purpose of making the energy transfer of excitons advantageous.

<Method for forming organic functional layer>
As a method for forming the organic functional layer in the organic EL device of the present invention, a known method can be suitably employed.
Hereinafter, a method for forming an organic functional layer (hole injection layer, hole transport layer, electron blocking layer, light emitting layer, hole blocking layer, electron transport layer, electron injection layer, etc.) will be described.

The method for forming the organic functional layer according to the present invention is not particularly limited, and for example, a vacuum evaporation method such as a dry process, a formation method by a wet process, etc. can be used, and a compound used for each layer can be used. Depending on the material, a method may be used in which an organic functional layer is formed by laminating properly using a wet process or a dry process. Here, the organic functional layer is preferably a layer formed by a wet process. That is, it is preferable to produce an organic EL element by a wet process. By producing the organic EL element by a wet process, it is possible to obtain an effect such that a homogeneous film (coating film) is easily obtained and pinholes are hardly generated. In addition, a film | membrane (coating film) here is a thing of the state dried after application | coating by a wet process.

Examples of the wet process include spin coating, casting, ink jet, printing, die coating, blade coating, roll coating, spray coating, curtain coating, and LB (Langmuir-Blodgett). From the viewpoint of obtaining a homogeneous thin film easily and high productivity, a method with high roll-to-roll method suitability such as a die coating method, a roll coating method, an ink jet method and a spray coating method is preferable.

Note that examples of the dry process include vapor deposition methods (resistance heating, EB method, etc.), sputtering methods, CVD methods, and the like.

In the present invention, as the liquid medium for dissolving or dispersing the organic EL element material constituting each layer, for example, ketones such as methyl ethyl ketone and cyclohexanone, fatty acid esters such as ethyl acetate, halogenated hydrocarbons such as dichlorobenzene, Aromatic hydrocarbons such as toluene, xylene, mesitylene and cyclohexylbenzene, aliphatic hydrocarbons such as cyclohexane, decalin and dodecane, and organic solvents such as DMF and DMSO can be used.

Further, as a dispersion method, it can be dispersed by a dispersion method such as ultrasonic wave, high shearing force dispersion or media dispersion.

Further, different film formation methods may be applied for each layer. When a vapor deposition method is employed for film formation, the vapor deposition conditions vary depending on the type of compound used, but generally the boat heating temperature is 50 to 450 ° C., the degree of vacuum is 1 × 10 ⁻⁶ to 1 × 10 ⁻² Pa, and the vapor deposition rate. It is desirable to select appropriately within a range of 0.01 to 50 nm / second, a substrate temperature of −50 to 300 ° C., and a thickness of 0.1 nm to 5 μm, preferably 5 to 200 nm.

In the formation of the organic functional layer according to the present invention, it is preferable to consistently produce from the hole injection layer to the cathode by one evacuation, but it may be taken out halfway and subjected to different film forming methods. In that case, it is preferable to perform the work in a dry inert gas atmosphere.

<anode>
As the anode in the organic EL element, a material having a work function (4 eV or more, preferably 4.5 eV or more) of a metal, an alloy, an electrically conductive compound, or a mixture thereof is preferably used. Specific examples of such an electrode material include metals such as Au, and conductive transparent materials such as CuI, ITO (indium tin oxide), SnO ₂ , and ZnO. Alternatively, an amorphous material such as IDIXO (In ₂ O ₃ —ZnO) capable of forming a transparent conductive film may be used.

For the anode, a thin film may be formed by depositing these electrode materials by a method such as vapor deposition or sputtering, and a pattern having a desired shape may be formed by a photolithography method, or when the pattern accuracy is not so high (about 100 μm or more) ), A pattern may be formed through a mask having a desired shape at the time of electrode material vapor deposition or sputtering.

Or when using the substance which can be apply | coated like an organic electroconductivity compound, wet film-forming methods, such as a printing system and a coating system, can also be used. When light emission is extracted from the anode, it is desirable that the light transmittance be larger than 10%, and the sheet resistance as the anode is several hundred Ω / sq. The following is preferred.

The thickness of the anode depends on the material, but is usually selected within the range of 10 nm to 1 μm, preferably within the range of 10 to 200 nm.

<cathode>
As the cathode, a material having a work function (4 eV or less) metal (referred to as an electron injecting metal), an alloy, an electrically conductive compound, and a mixture thereof as an electrode material is used. Specific examples of such electrode materials include sodium, sodium-potassium alloy, magnesium, lithium, magnesium / copper mixture, magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, aluminum / aluminum oxide (Al ₂ O ₃ ) Mixtures, indium, lithium / aluminum mixtures, aluminum, rare earth metals and the like. Among these, from the point of durability against electron injection and oxidation, etc., a mixture of an electron injecting metal and a second metal which is a stable metal having a larger work function than this, for example, a magnesium / silver mixture, Magnesium / aluminum mixtures, magnesium / indium mixtures, aluminum / aluminum oxide (Al ₂ O ₃ ) mixtures, lithium / aluminum mixtures, aluminum and the like are preferred.

The cathode can be produced by forming a thin film of these electrode materials by a method such as vapor deposition or sputtering. The sheet resistance as a cathode is several hundred Ω / sq. The following are preferable, and the thickness is usually selected within the range of 10 nm to 5 μm, preferably within the range of 50 to 200 nm.

In addition, in order to transmit the emitted light, if either one of the anode or the cathode of the organic EL element is transparent or translucent, the emission luminance is improved, which is convenient.

Further, after producing the above metal on the cathode with a thickness of 1 to 20 nm, a transparent or semi-transparent cathode can be produced by producing the conductive transparent material mentioned in the description of the anode on the cathode, By applying this, an element in which both the anode and the cathode are light transmissive can be manufactured.

<Support substrate>
The support substrate (hereinafter also referred to as a substrate, substrate, substrate, support, etc.) that can be used in the organic EL device of the present invention is not particularly limited in the type of glass, plastic, etc., and is transparent. Or opaque. When extracting light from the support substrate side, the support substrate is preferably transparent. Examples of the transparent support substrate preferably used include glass, quartz, and a transparent resin film. A particularly preferable support substrate is a resin film capable of giving flexibility to the organic EL element.

Examples of the resin film include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyethylene, polypropylene, cellophane, cellulose diacetate, cellulose triacetate (TAC), cellulose acetate butyrate, cellulose acetate propionate ( CAP), cellulose esters such as cellulose acetate phthalate, cellulose nitrate or derivatives thereof, polyvinylidene chloride, polyvinyl alcohol, polyethylene vinyl alcohol, syndiotactic polystyrene, polycarbonate, norbornene resin, polymethylpentene, polyether ketone, polyimide , Polyethersulfone (PES), polyphenylene sulfide, polysulfones Cycloolefins such as polyetherimide, polyetherketoneimide, polyamide, fluororesin, nylon, polymethyl methacrylate, acrylic, or polyarylate, Arton (trade name, manufactured by JSR) or Appel (trade name, manufactured by Mitsui Chemicals) Based resins and the like.

An inorganic film, an organic film, or a hybrid film of both may be formed on the surface of the resin film, and the water vapor permeability (25 ± 0.5 ° C.) measured by a method according to JIS K 7129: 1992. , Relative humidity (90 ± 2)% RH) is preferably 0.01 g / (m ² · 24 h) or less gas barrier film, and further measured by a method according to JIS K 7126: 1987. It is a high gas barrier film having an oxygen permeability of 1 × 10 ⁻³ mL / (m ² · 24 h · atm) or less and a water vapor permeability of 1 × 10 ⁻⁵ g / (m ² · 24 h) or less. Is preferred.

The material for forming the gas barrier film may be any material that has a function of suppressing entry of elements that cause deterioration of elements such as moisture and oxygen. For example, silicon oxide, silicon dioxide, silicon nitride, and the like can be used. Furthermore, in order to improve the brittleness of the film, it is more preferable to have a laminated structure of these inorganic layers and layers made of organic materials. Although there is no restriction | limiting in particular about the lamination | stacking order of an inorganic layer and an organic layer, It is preferable to laminate | stack both alternately several times.

The method for forming the gas barrier film is not particularly limited. For example, the vacuum deposition method, sputtering method, reactive sputtering method, molecular beam epitaxy method, cluster ion beam method, ion plating method, plasma polymerization method, atmospheric pressure plasma weight A combination method, a plasma CVD method, a laser CVD method, a thermal CVD method, a coating method, and the like can be used, but an atmospheric pressure plasma polymerization method as described in JP-A-2004-68143 is particularly preferable.

Examples of the opaque support substrate include metal plates such as aluminum and stainless steel, films, opaque resin substrates, ceramic substrates, and the like.

The external extraction quantum efficiency at room temperature (25 ° C.) of light emission of the organic EL device of the present invention is preferably 1% or more, and more preferably 5% or more.

Here, external extraction quantum efficiency (%) = (number of photons emitted to the outside of the organic EL element / number of electrons passed through the organic EL element) × 100.

Also, a hue improvement filter such as a color filter may be used in combination, or a color conversion filter that converts the emission color from the organic EL element into multiple colors using a phosphor may be used in combination.

<Sealing>
Examples of the sealing means used for sealing the organic EL element of the present invention include a method of bonding a sealing member, an electrode, and a support substrate with an adhesive. As a sealing member, it should just be arrange | positioned so that the display area | region of an organic EL element may be covered, and it may be concave plate shape or flat plate shape. Moreover, transparency and electrical insulation are not particularly limited.

Specific examples include a glass plate, a polymer plate / film, and a metal plate / film. Examples of the glass plate include soda-lime glass, barium / strontium-containing glass, lead glass, aluminosilicate glass, borosilicate glass, barium borosilicate glass, and quartz. Examples of the polymer plate include polycarbonate, acrylic, polyethylene terephthalate, polyether sulfide, and polysulfone. Examples of the metal plate include those made of one or more metals or alloys selected from the group consisting of stainless steel, iron, copper, aluminum, magnesium, nickel, zinc, chromium, titanium, molybdenum, silicon, germanium, and tantalum.

In the present invention, a polymer film and a metal film can be preferably used because the organic EL element can be thinned. Furthermore, the polymer film has an oxygen permeability measured by a method according to JIS K 7126: 1987 of 1 × 10 ⁻³ mL / (m ² · 24 h · atm) or less, and a method according to JIS K 7129: 1992. The measured water vapor permeability (25 ± 0.5 ° C., relative humidity (90 ± 2)%) is preferably 1 × 10 ⁻³ g / (m ² · 24 h) or less.

For processing the sealing member into a concave shape, sandblasting, chemical etching, or the like is used.

Specific examples of the adhesive include photocuring and thermosetting adhesives having reactive vinyl groups of acrylic acid oligomers and methacrylic acid oligomers, and moisture curing adhesives such as 2-cyanoacrylates. be able to. Moreover, heat | fever and chemical-curing types (2 liquid mixing), such as an epoxy type, can be mentioned. Moreover, hot-melt type polyamide, polyester, and polyolefin can be mentioned. Moreover, a cationic curing type ultraviolet curing epoxy resin adhesive can be mentioned.

In addition, since an organic EL element may deteriorate by heat processing, what can be adhesive-hardened from room temperature (25 degreeC) to 80 degreeC is preferable. Further, a desiccant may be dispersed in the adhesive. Application | coating of the adhesive agent to a sealing part may use commercially available dispenser, and may print like screen printing.

It is also preferable that the electrode and the organic functional layer are coated on the outside of the electrode facing the support substrate with the organic functional layer interposed therebetween, and an inorganic or organic layer is formed in contact with the support substrate to form a sealing film. Can be. In this case, the material for forming the film may be any material that has a function of suppressing intrusion of elements that cause deterioration of elements such as moisture and oxygen. For example, silicon oxide, silicon dioxide, silicon nitride, or the like may be used. it can.

Furthermore, in order to improve the brittleness of the film, it is preferable to have a laminated structure of these inorganic layers and layers made of organic materials. There are no particular limitations on the method of forming these films. For example, vacuum deposition, sputtering, reactive sputtering, molecular beam epitaxy, cluster ion beam, ion plating, plasma polymerization, atmospheric pressure plasma A combination method, a plasma CVD method, a laser CVD method, a thermal CVD method, a coating method, or the like can be used.

In the gap between the sealing member and the display area of the organic EL element, an inert gas such as nitrogen or argon, or an inert liquid such as fluorinated hydrocarbon or silicon oil can be injected in the gas phase and liquid phase. preferable. A vacuum can also be used. Moreover, a hygroscopic compound can also be enclosed inside.

Examples of the hygroscopic compound include metal oxides (for example, sodium oxide, potassium oxide, calcium oxide, barium oxide, magnesium oxide, aluminum oxide) and sulfates (for example, sodium sulfate, calcium sulfate, magnesium sulfate, cobalt sulfate). Etc.), metal halides (eg calcium chloride, magnesium chloride, cesium fluoride, tantalum fluoride, cerium bromide, magnesium bromide, barium iodide, magnesium iodide etc.), perchloric acids (eg perchloric acid) Barium, magnesium perchlorate, and the like), and anhydrous salts are preferably used in sulfates, metal halides, and perchloric acids.

《Protective film, protective plate》
In order to increase the mechanical strength of the element, a protective film or a protective plate may be provided outside the sealing film or sealing film on the side facing the support substrate with the organic functional layer interposed therebetween. In particular, when sealing is performed with a sealing film, the mechanical strength is not necessarily high, and thus it is preferable to provide such a protective film and a protective plate. As a material that can be used for this, the same glass plate, polymer plate / film, metal plate / film, etc. used for the sealing can be used, but the polymer film is light and thin. Is preferably used.

《Light extraction enhancement technology》
An organic EL element emits light inside a layer having a higher refractive index than air (within a refractive index of about 1.6 to 2.1), and only about 15 to 20% of the light generated in the light emitting layer is emitted. It is generally said that it cannot be taken out. This is because light incident on the interface (interface between the transparent substrate and air) at an angle θ greater than the critical angle causes total reflection and cannot be taken out of the element, or between the transparent electrode or light emitting layer and the transparent substrate. This is because the light undergoes total reflection between the light, the light is guided through the transparent electrode or the light emitting layer, and as a result, the light escapes in the side surface direction of the element.

As a technique for improving the light extraction efficiency, for example, a method of forming irregularities on the surface of the transparent substrate to prevent total reflection at the transparent substrate and the air interface (for example, US Pat. No. 4,774,435), A method for improving efficiency by providing light condensing property (for example, Japanese Patent Laid-Open No. 63-134795), a method for forming a reflective surface on the side surface of an element (for example, Japanese Patent Laid-Open No. 1-220394), a substrate A method of forming an antireflection film by introducing a flat layer having an intermediate refractive index between the substrate and the light emitter (for example, Japanese Patent Laid-Open No. 62-172691), lower refractive index than the substrate between the substrate and the light emitter A method of introducing a flat layer having a refractive index (for example, Japanese Patent Application Laid-Open No. 2001-202827), and a method of forming a diffraction grating between any one of a substrate, a transparent electrode layer and a light emitting layer (including between the substrate and the outside) (JP-A JP), etc. 1-283751 can be mentioned.

In the present invention, these methods can be used in combination with the organic EL device of the present invention. However, a method of introducing a flat layer having a lower refractive index than the substrate between the substrate and the light emitter, or a substrate, transparent A method of forming a diffraction grating between any one of the electrode layer and the light emitting layer (including between the substrate and the outside) can be suitably used.

In the present invention, by combining these means, it is possible to obtain an element having higher luminance or durability.

When a low refractive index medium is formed between the transparent electrode and the transparent substrate with a thickness longer than the wavelength of light, the light extracted from the transparent electrode has a higher extraction efficiency to the outside as the refractive index of the medium is lower. Become.

Examples of the low refractive index layer include aerogel, porous silica, magnesium fluoride, and a fluorine-based polymer. Since the refractive index of the transparent substrate is generally in the range of about 1.5 to 1.7, the low refractive index layer preferably has a refractive index of about 1.5 or less. Moreover, it is more preferable that it is 1.35 or less.

Also, the thickness of the low refractive index medium is preferably at least twice the wavelength in the medium. This is because the effect of the low-refractive index layer is reduced when the thickness of the low-refractive index medium is about the wavelength of light and the electromagnetic wave exuded by evanescent enters the substrate.

The method of introducing a diffraction grating into an interface that causes total reflection or in any medium has a feature that the effect of improving the light extraction efficiency is high. This method uses the property that the diffraction grating can change the direction of light to a specific direction different from refraction by so-called Bragg diffraction, such as first-order diffraction or second-order diffraction. Of the light, the light that cannot go out due to total reflection between layers, etc., is diffracted by introducing a diffraction grating in any layer or medium (in the transparent substrate or transparent electrode), It tries to take out light.

It is desirable that the diffraction grating to be introduced has a two-dimensional periodic refractive index. This is because light emitted from the light-emitting layer is randomly generated in all directions, so in a general one-dimensional diffraction grating having a periodic refractive index distribution only in a certain direction, only light traveling in a specific direction is diffracted. The light extraction efficiency does not increase so much.
However, by making the refractive index distribution a two-dimensional distribution, light traveling in all directions is diffracted, and the light extraction efficiency is increased.

The position where the diffraction grating is introduced may be in any one of the layers or in the medium (in the transparent substrate or the transparent electrode), but is preferably in the vicinity of the light emitting layer where light is generated. At this time, the period of the diffraction grating is preferably in the range of about 1/2 to 3 times the wavelength of light in the medium. The arrangement of the diffraction grating is preferably two-dimensionally repeated, such as a square lattice, a triangular lattice, or a honeycomb lattice.

《Condensing sheet》
The organic EL device of the present invention can be processed to provide, for example, a structure on a microlens array on the light extraction side of a support substrate (substrate), or combined with a so-called condensing sheet, for example, in a specific direction, By condensing in the front direction with respect to the element light emitting surface, the luminance in a specific direction can be increased.

As an example of a microlens array, quadrangular pyramids having a side of 30 μm and an apex angle of 90 degrees are arranged two-dimensionally on the light extraction side of the substrate. One side is preferably within a range of 10 to 100 μm. If it is smaller than this, the effect of diffraction is generated and colored, and if it is too large, the thickness becomes thick, which is not preferable.

As the condensing sheet, it is possible to use, for example, a sheet that has been put to practical use in an LED backlight of a liquid crystal display device. As such a sheet, for example, a brightness enhancement film (BEF) manufactured by Sumitomo 3M Limited can be used. As the shape of the prism sheet, for example, the base material may be formed by forming a △ -shaped stripe having a vertex angle of 90 degrees and a pitch of 50 μm, or the vertex angle is rounded and the pitch is changed randomly. Other shapes may be used.

Further, in order to control the light emission angle from the organic EL element, a light diffusion plate / film may be used in combination with the light collecting sheet. For example, a diffusion film (light-up) manufactured by Kimoto Co., Ltd. can be used.

<Application>
The organic EL element of the present invention can be used as a display device, a display, and various light emission sources.

For example, lighting devices (home lighting, interior lighting), clock and liquid crystal backlights, billboard advertisements, traffic lights, light sources of optical storage media, light sources of electrophotographic copying machines, light sources of optical communication processors, light Although the light source of a sensor etc. are mentioned, It is not limited to this, Especially, it can use effectively for the use as a backlight of a liquid crystal display device, and a light source for illumination.

In the organic EL device of the present invention, patterning may be performed by a metal mask, an ink jet printing method, or the like during film formation, if necessary. In the case of patterning, only the electrode may be patterned, the electrode and the light emitting layer may be patterned, or the entire layer of the element may be patterned. In the fabrication of the element, a conventionally known method is used. Can do.

<Display device>
Hereinafter, an example of a display device having the organic EL element of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic perspective view showing an example of the configuration of a display device composed of the organic EL element of the present invention, which displays image information by light emission of the organic EL element, for example, a display such as a mobile phone FIG. As shown in FIG. 1, the display 1 includes a display unit A having a plurality of pixels, a control unit B that performs image scanning of the display unit A based on image information, and the like.

The control unit B is electrically connected to the display unit A. The control unit B sends a scanning signal and an image data signal to each of the plurality of pixels based on image information from the outside. As a result, each pixel sequentially emits light according to the image data signal for each scanning line by the scanning signal, and the image information is displayed on the display unit A.

FIG. 2 is a schematic diagram of the display unit A shown in FIG.
The display unit A includes a wiring unit including a plurality of scanning lines 5 and data lines 6, a plurality of pixels 3 and the like on a substrate.

The main components of the display unit A will be described below.

FIG. 2 shows a case where the light emitted from the pixel 3 is extracted in the direction of the white arrow (downward). Each of the scanning lines 5 and the plurality of data lines 6 in the wiring portion is made of a conductive material. The scanning lines 5 and the data lines 6 are orthogonal to each other in a grid pattern and are connected to the pixels 3 at the orthogonal positions (details are not shown).

When the scanning signal is transmitted from the scanning line 5, the pixel 3 receives the image data signal from the data line 6 and emits light according to the received image data.

A full-color display is possible by arranging pixels in the red region, the green region, and the blue region as appropriate in parallel on the same substrate.

《Lighting device》
One mode of a lighting device including the organic EL element of the present invention will be described.

The non-light emitting surface of the organic EL device of the present invention is covered with a glass case, a 300 μm thick glass substrate is used as a sealing substrate, and an epoxy photocurable adhesive (LUX The track LC0629B) is applied, and this is overlaid on the cathode and brought into close contact with the transparent support substrate, irradiated with UV light from the glass substrate side, cured and sealed, and an illumination device as shown in FIGS. Can be formed.

FIG. 3 shows a schematic diagram of a lighting device, and the organic EL element 101 of the present invention is covered with a glass cover 102 (in the sealing operation with the glass cover, the organic EL element 101 is brought into contact with the atmosphere. Without using a glove box under a nitrogen atmosphere (in an atmosphere of high-purity nitrogen gas with a purity of 99.999% or higher).

4 shows a cross-sectional view of the lighting device. In FIG. 4, reference numeral 105 denotes a cathode, reference numeral 106 denotes an organic functional layer (or light emitting unit), and reference numeral 107 denotes a glass substrate with a transparent electrode. The glass cover 102 is filled with nitrogen gas 108 and a water catching agent 109 is provided.

Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited thereto.

[Example 1]
For the fluorescent compounds of the present invention shown in Tables I-1 and I-2 and the following comparative compounds 1 to 30, the fluorescence quantum yields in the solution state and the film state were evaluated.

<Measurement of absolute quantum yield in solution>
The compounds shown in Tables I-1 and I-2 were each dissolved in 2-methyltetrahydrofuran and the absolute quantum yield was measured. The absolute quantum yield was measured using an absolute quantum yield measuring apparatus C9920-02 (manufactured by Hamamatsu Photonics).

<< Measurement of absolute quantum yield in film state >>
A quartz substrate having a size of 30 mm × 30 mm and a thickness of 0.7 mm was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and subjected to UV ozone cleaning for 5 minutes. This transparent substrate was fixed to a substrate holder of a commercially available vacuum deposition apparatus.
An optimum amount of each of the fluorescent light emitting compounds shown in Tables I-1 and I-2 was filled in a vapor emitting crucible in a vacuum vapor deposition apparatus. As the evaporation crucible, a crucible made of a resistance heating material made of molybdenum or tungsten was used.
After reducing the pressure to 1 × 10 ⁻⁴ Pa, each fluorescent compound was deposited at a deposition rate of 0.1 nm / second to form a single film having a thickness of 30 nm.
The absolute quantum yield (PLQE) of each produced fluorescent light emitting compound single film was measured. The absolute quantum yield was measured using an absolute quantum yield measuring apparatus C9920-02 (manufactured by Hamamatsu Photonics).

"Evaluation results"
For each fluorescent compound, the ratio of the absolute quantum yield in the measured solution state to the absolute quantum yield in the film state (absolute quantum yield in the film state / absolute quantum yield in the solution state) ) Was evaluated according to the following evaluation criteria.
The evaluation results are shown in Tables I-1 and I-2.

A: Absolute quantum yield in the film state / absolute quantum yield in the solution state is 0.75 or more (best, pass)
○: Absolute quantum yield in film state / absolute quantum yield in solution state is 0.5 or more and less than 0.75 (good, pass)
X: Absolute quantum yield in the film state / absolute quantum yield in the solution state is less than 0.5 (defective or rejected)

As is apparent from Tables I-1 and I-2, the fluorescent compound of the present invention has a smaller decrease in absolute quantum yield in the film state than the comparative compound of the comparative example, that is, even in the solid state. It can be seen that the absolute quantum yield is maintained. This is probably because the fluorescent compound of the present invention has the substituent Y, so that spontaneous aggregation of molecules is unlikely to occur, and as a result, concentration quenching did not occur even in the solid state. It is done.
From the above, it was confirmed that the fluorescent compound having the structure represented by the general formula (1) is useful for suppressing concentration quenching in the solid state.

[Example 2]
<Production of evaluation lighting device>
Lighting devices for evaluation 201 to 270 were produced as follows.

<Production of Evaluation Lighting Device 201>
First, a surface treatment with ozone was performed on an ITO (indium tin oxide) -glass substrate (ITO film thickness 150 nm) that had been patterned and cleaned in advance. Immediately after the ozone treatment, 4,4 ′, 4 ″ -tris (N, N- (2-naphthyl) phenylamino) triphenylamine (2-TNATA, film thickness 50 nm) as a hole injection material was deposited on the ITO film. A film was formed.
Next, N, N′-di-[(1-naphthyl) -N, N′-diphenyl] -1,1 ′ ′-biphenyl) -4,4′-diamine was formed as a hole transport material. (25 nm).
Next, as a light emitting material (fluorescent compound), a film in which the comparative compound 4 was doped at a ratio of 3% by mass with respect to 9,10-di (2-naphthyl) anthracene (ADN) was formed by co-evaporation. (30 nm).
Next, tris (8-quinolinolato) aluminum (Alq ₃ ) was formed as an electron transport material (30 nm), then lithium fluoride (LiF) (1.0 nm) as an electron injection material and aluminum as a cathode (100 nm) were sequentially laminated to produce an organic EL element for evaluation.

After manufacturing the organic EL element, the non-light-emitting surface of the organic EL element is covered with a glass case in an atmosphere of high purity nitrogen gas with a purity of 99.999% or more, and a glass substrate having a thickness of 300 μm is used as a sealing substrate. Then, an epoxy-based photo-curing adhesive (Lux Track LC0629B manufactured by Toagosei Co., Ltd.) is applied as a sealing material to the periphery, and this is placed on the cathode to be in close contact with the transparent support substrate and irradiated with UV light from the glass substrate side. Then, it was cured and sealed to produce an evaluation illumination device 201 having a configuration as shown in FIGS.

<Production of Evaluation Lighting Devices 202 to 270>
Evaluation illumination devices 202 to 270 were produced in the same manner except that the light emitting material was changed as described in Tables II-1 and II-2 in the production of the evaluation illumination device 201.

<Evaluation>
The manufactured lighting devices for evaluation 201 to 270 were evaluated for luminous efficiency and half life.
The evaluation results are shown in Tables II-1 and II-2.

<Measurement of luminous efficiency>
About each produced lighting apparatus for evaluation, lighting was performed under a constant current density condition of ^2.5 mA / cm ² at room temperature (25 ° C.), and light emission was performed using a spectral radiance meter CS-2000 (manufactured by Konica Minolta). The luminance was measured, and the light emission efficiency (external extraction quantum efficiency) at the current value was determined.
In Tables II-1 and II-2, the luminous efficiency is shown as a relative value. For example, the luminous efficiency of the lighting devices 201, 202, and 204 to 219 is that the luminous efficiency of the lighting device 203 is 1.0. Relative value.

<Measurement of half-life>
About each produced lighting apparatus for evaluation, the brightness | luminance was measured using the spectral radiance meter CS-2000, and the time (LT50) for which the measured brightness | luminance was reduced to half was calculated | required as a half life. The driving condition was a current value of 15 mA / cm ² .
In Tables II-1 and II-2, the half-life is shown as a relative value. For example, the half-lives of the lighting devices 201, 202, and 204 to 219 are set such that the half-life of the lighting device 203 is 1.0. Relative value.

As is apparent from Tables II-1 and II-2, the lighting device containing the fluorescent compound of the present invention has higher luminous efficiency and half of the lighting device containing the comparative compound of the comparative example. It can be seen that the lifetime has been extended. This is because the fluorescent compound of the present invention has the substituent Y, so that spontaneous aggregation of molecules does not easily occur, and as a result, there is no decrease in luminous efficiency due to concentration quenching or the like. it is conceivable that.

[Example 3]
<Production of evaluation lighting device>
Evaluation lighting devices 301 to 318 were produced as follows.

<Production of Evaluation Lighting Device 301>
(Formation of anode)
An ITO (indium tin oxide) film having a thickness of 150 nm was formed as an anode on a glass substrate (transparent substrate) having a thickness of 50 mm × 50 mm and a thickness of 0.7 mm, and this ITO transparent electrode was formed after patterning. The attached transparent substrate was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and subjected to UV ozone cleaning for 5 minutes.
Each of the resistance heating boats for vapor deposition in the vacuum vapor deposition apparatus was filled with the constituent material of each layer in an amount optimal for device fabrication. The resistance heating boat was made of molybdenum or tungsten.

(Formation of hole injection layer)
After reducing the vacuum to 1 × 10 ⁻⁴ Pa, the resistance heating boat containing HI-1 was energized and heated, and deposited on the ITO transparent electrode at a deposition rate of 0.1 nm / second. A hole injection layer was formed.

(Formation of hole transport layer)
Next, HT-1 was vapor-deposited at a vapor deposition rate of 1.0 kg / sec to form a 30 nm-thick hole transport layer.

(Formation of light emitting layer)
Next, the resistance heating boat containing the host compound H-1, the phosphorescent compound Dp-1 and the comparative compound 4 is energized and heated, and the host compound H-1, the phosphorescent compound Dp-1 and the fluorescence are emitted. The deposition rate was 0.56 Å / sec, 0.1 Å / sec, and 0.006 Å / sec so that the comparative compound 4 as the active compound would be 84.5 vol%, 15 vol%, and 0.5 vol%, respectively. Were co-evaporated on the hole transport layer to form a light emitting layer having a thickness of 30 nm.

(Formation of electron transport layer)
Next, a first electron transport layer and a second electron transport layer were formed on the light emitting layer as electron transport layers. Specifically, HB-1 was deposited at a deposition rate of 1.0 kg / sec to form a first electron transport layer having a thickness of 30 nm. Furthermore, ET-1 was vapor-deposited thereon at a vapor deposition rate of 1.0 kg / second to form a second electron transport layer having a thickness of 30 nm.

(Formation of cathode)
Then, after vapor-depositing lithium fluoride to a thickness of 0.5 nm, aluminum was deposited to a thickness of 100 nm to form a cathode, and an organic EL element for evaluation was produced.

After manufacturing the organic EL element, the non-light-emitting surface of the organic EL element is covered with a glass case in an atmosphere of high purity nitrogen gas with a purity of 99.999% or more, and a glass substrate having a thickness of 300 μm is used as a sealing substrate. Then, an epoxy-based photo-curing adhesive (Lux Track LC0629B manufactured by Toagosei Co., Ltd.) is applied as a sealing material to the periphery, and this is placed on the cathode to be in close contact with the transparent support substrate and irradiated with UV light from the glass substrate side. Then, it was cured and sealed to produce an evaluation illumination device 301 having a structure as shown in FIGS.

<Production of Evaluation Lighting Devices 302 to 318>
Evaluation illumination devices 302 to 318 were prepared in the same manner except that the fluorescent light emitting compound was changed as shown in Table III in the production of the evaluation illumination device 301.

<Evaluation>
Luminous efficiency was evaluated for the manufactured illumination devices for evaluation 301 to 318.
The evaluation results are shown in Table III.

<Measurement of luminous efficiency>
About each produced lighting apparatus for evaluation, lighting was performed under a constant current density condition of ^2.5 mA / cm ² at room temperature (25 ° C.), and light emission was performed using a spectral radiance meter CS-2000 (manufactured by Konica Minolta). The luminance was measured, and the light emission efficiency (external extraction quantum efficiency) at the current value was determined.
In Table III, the luminous efficiency is shown as a relative value. For example, the luminous efficiency of the lighting devices 302 to 306 is a relative value when the luminous efficiency of the lighting device 301 is 1.0.

As is apparent from Table III, it can be seen that the lighting device containing the fluorescent compound of the present invention has higher luminous efficiency than the lighting device containing the comparative compound of the comparative example. This is because the fluorescent compound of the present invention has the substituent Y, so that spontaneous aggregation of molecules does not easily occur, and as a result, there is no decrease in luminous efficiency due to concentration quenching or the like. it is conceivable that.

[Example 4]
<Production of evaluation lighting device>
Illumination devices for evaluation 401 to 420 were produced in the same manner as in Example 3, except that the phosphorescent compound and the fluorescent compound were changed as described in Table IV.

<Evaluation>
The luminous efficiency of the produced evaluation lighting devices 401 to 420 was evaluated.
The evaluation results are shown in Table IV.

<Measurement of luminous efficiency>
About each produced lighting apparatus for evaluation, lighting was performed under a constant current density condition of ^2.5 mA / cm ² at room temperature (25 ° C.), and light emission was performed using a spectral radiance meter CS-2000 (manufactured by Konica Minolta). The luminance was measured, and the light emission efficiency (external extraction quantum efficiency) at the current value was determined.
In Table IV, the luminous efficiency is shown as a relative value. For example, the luminous efficiency of the lighting devices 402 to 407 is a relative value when the luminous efficiency of the lighting device 401 is 1.0.

As is apparent from Table IV, it can be seen that the lighting device containing the fluorescent compound of the present invention has higher luminous efficiency than the lighting device containing the comparative compound of the comparative example. This is because the fluorescent compound of the present invention has the substituent Y, so that spontaneous aggregation of molecules does not easily occur, and as a result, there is no decrease in luminous efficiency due to concentration quenching or the like. it is conceivable that.

[Example 5]
<Production of evaluation lighting device>
Evaluation lighting devices 501 to 519 were produced as follows.

<< Production of Evaluation Lighting Device 501 >>
As an anode, after patterning a substrate (NH45 manufactured by NH Techno Glass Co., Ltd.) on which a 100 nm × 100 mm × 1.1 mm glass substrate is formed with ITO (indium tin oxide) 100 nm, this ITO transparent electrode is provided. The transparent support substrate was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and subjected to UV ozone cleaning for 5 minutes.
On this transparent support substrate, using a solution obtained by diluting poly (3,4-ethylenedioxythiophene) -polystyrene sulfonate (PEDOT / PSS, Baytron, Baytron P Al 4083) to 70 mass% with pure water, 3000 rpm After forming a thin film by spin coating under a condition of 30 seconds, the film was dried at 200 ° C. for 1 hour to provide a hole injection layer having a thickness of 20 nm.

This transparent support substrate was fixed to a substrate holder of a commercially available vacuum vapor deposition apparatus, and each of the vapor deposition crucibles in the vacuum vapor deposition apparatus was filled with the constituent material of each layer in an amount optimal for device fabrication. As the evaporation crucible, a crucible made of a resistance heating material made of molybdenum or tungsten was used.

After reducing the vacuum to 1 × 10 ⁻⁴ Pa, α-NPD was deposited on the hole injection layer at a deposition rate of 0.1 nm / second to form a 40 nm thick hole transport layer.

Next, H-2 is used as the host compound, Dp-3 is used as the thermally activated delayed fluorescent compound, and Comparative Compound 8 is used as the fluorescent compound, and the ratios are 84.5 vol%, 15 vol%, and 0.5 vol, respectively. % Was co-evaporated at a deposition rate of 0.1 nm / second to form a light-emitting layer having a thickness of 30 nm.

Thereafter, TPBi (1,3,5-tris (N-phenylbenzimidazol-2-yl) was deposited at a deposition rate of 0.1 nm / second to form an electron transport layer having a thickness of 30 nm.

Furthermore, after forming sodium fluoride with a thickness of 1 nm, aluminum was deposited with a thickness of 100 nm to form a cathode.

The non-light-emitting surface side of the above element was covered with a can-shaped glass case in an atmosphere of high-purity nitrogen gas with a purity of 99.999% or more, and an electrode lead-out wiring was installed to produce an evaluation illumination device 501.

<Production of Evaluation Lighting Devices 502 to 519>
Evaluation illumination devices 502 to 519 were produced in the same manner as in the production of the evaluation illumination device 501, except that the fluorescent compound was changed as described in Table V.

<Evaluation>
Luminous efficiency was evaluated for the manufactured illumination devices for evaluation 501 to 519.
The evaluation results are shown in Table V.

<Measurement of luminous efficiency>
About each produced lighting apparatus for evaluation, lighting was performed under a constant current density condition of ^2.5 mA / cm ² at room temperature (25 ° C.), and light emission was performed using a spectral radiance meter CS-2000 (manufactured by Konica Minolta). The luminance was measured, and the light emission efficiency (external extraction quantum efficiency) at the current value was determined.
In Table V, the luminous efficiency is shown as a relative value. For example, the luminous efficiency of the lighting devices 502 to 508 is a relative value when the luminous efficiency of the lighting device 501 is 1.0.

As is apparent from Table V, it can be seen that the lighting device containing the fluorescent compound of the present invention has higher luminous efficiency than the lighting device containing the comparative compound of the comparative example. This is because the fluorescent compound of the present invention has the substituent Y, so that spontaneous aggregation of molecules does not easily occur, and as a result, there is no decrease in luminous efficiency due to concentration quenching or the like. it is conceivable that.

INDUSTRIAL APPLICABILITY The present invention can be particularly suitably used for providing a fluorescent compound, an organic material composition, a luminescent film, an organic electroluminescence element material, and an organic electroluminescence element that suppress concentration quenching in a solid state. .

DESCRIPTION OF SYMBOLS 1 Display 3 Pixel 5 Scan line 6 Data line 101 Organic EL element 102 Glass cover 105 Cathode 106 Organic functional layer (light emitting unit)
107 Glass substrate with transparent electrode 108 Nitrogen gas 109 Water capturing agent A Display unit B Control unit

Claims

A fluorescent compound having a structure represented by the following general formula (1).

(In the general formula (1), X represents a π-conjugated condensed ring having a 14π electron system or more. Y represents a deuterium atom, halogen atom, cyano group, nitro group, hydroxy group, mercapto group, alkyl group, cycloalkyl group. Group, alkenyl group, alkynyl group, heterocyclic group, alkoxy group, cycloalkoxy group, aryloxy group, alkylthio group, cycloalkylthio group, arylthio group, alkoxycarbonyl group, aryloxycarbonyl group, sulfamoyl group, acyl group, acyloxy group Amide group, carbamoyl group, ureido group, sulfinyl group, alkylsulfonyl group, arylsulfonyl group, heteroarylsulfonyl group, amino group, fluorinated hydrocarbon group, triarylsilyl group, diarylalkylsilyl group, aryldialkylsilyl group, Trialkylsilyl group, An acid ester group, a phosphite group, a phosphono group, a phenyl group, or a group having a structure represented by the following general formula (2) is represented, and these may further have a substituent. At least one is a group having a structure represented by the following general formula (2): Y may be the same as or different from each other when there are a plurality of Y. n is the π-conjugated condensation. Represents the number of Ys that can be substituted for hydrogen atoms on the ring, and represents an integer from 1 to the maximum number.)

(In the general formula (2), R 1 to R 5 are each independently a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a nitro group, a hydroxy group, a mercapto group, an alkyl group, a cycloalkyl group, or an alkenyl group. Alkynyl group, heterocyclic group, alkoxy group, cycloalkoxy group, aryloxy group, alkylthio group, cycloalkylthio group, arylthio group, alkoxycarbonyl group, aryloxycarbonyl group, sulfamoyl group, acyl group, acyloxy group, amide group, Carbamoyl group, ureido group, sulfinyl group, alkylsulfonyl group, arylsulfonyl group or heteroarylsulfonyl group, amino group, fluorinated hydrocarbon group, triarylsilyl group, diarylalkylsilyl group, aryldialkylsilyl group, trialkylsilyl group , Represents an ester group, a phosphite group, or a phosphono group, tables in at least one of these further may have a substituent .R 1 and R 5, the following general formula (3) or (4) * 1 represents a binding site with X.)

(In General Formula (3), A represents a carbon atom or a silicon atom. R 6 to R 8 each independently represents the same atom or substituent as R 1 to R 5 in General Formula (2). However, at least one of R 6 to R 8 is an alkyl group having 1 or more carbon atoms. * 2 represents a bonding site with an adjacent atom.)

(In General Formula (4), R 9 and R 10 each independently represent the same atom or substituent as R 1 to R 5 in General Formula (2), but at least one of them has 1 or more carbon atoms. * 3 represents a bonding site with an adjacent atom, R 1 to R 10 in the general formulas (2) to (4) are substituted or unsubstituted aliphatic groups bonded to each other. A ring may be formed, but an aromatic ring is not further condensed to the formed aliphatic ring.)
The fluorescent compound according to claim 1, wherein at least one of R 1 and R 5 in the general formula (2) is represented by the general formula (3).
The fluorescent compound according to claim 1 or 2, wherein the fluorescent compound having a structure represented by the general formula (1) has a structure represented by the following general formula (1a).

(In the general formula (1a), X represents a π-conjugated condensed ring having a 14π electron system or more. Y represents a deuterium atom, a triarylsilyl group, a diarylalkylsilyl group, an aryldialkylsilyl group, a trialkylsilyl group, A phenyl group or a group having a structure represented by the following general formula (2a), which may further have a substituent, wherein at least one of Y is represented by the following general formula (2a); Y may be the same or different when there are a plurality of groups, and n is the number of Ys that can be substituted for hydrogen atoms on the π-conjugated condensed ring. Represents an integer from 1 to the maximum number.)

(In the general formula (2a), R 1 to R 5 each independently represent the same atom or substituent as R 1 to R 5 in the general formula (2), but at least one of R 1 and R 5 Is a linear, branched or cyclic alkyl group having 2 or more carbon atoms, or at least one of R 1 and R 2 and R 4 and R 5 is bonded to each other to form a substituted or unsubstituted aliphatic ring. (The aromatic ring is not further condensed to the aliphatic ring formed at this time.)
The X in the general formula (1) or (1a) is a π-conjugated condensed ring having a structure represented by any one of the following general formulas (5) to (21). The fluorescent compound according to claim 1.

(In the general formulas (5) to (19), R represents a hydrogen atom or a bonding site with Y in the general formula (1) or (1a), but not all of them are hydrogen atoms. R may be the same as or different from each other.
In the general formulas (20) and (21), L represents —CR 11 R 12 —, —O—, —NR 13 —, —SiR 14 R 15 —, or —S—. The plurality of L may be the same as or different from each other. R and R 11 to R 15 each independently represent a hydrogen atom or a bonding site with Y in the general formula (1) or (1a), but not all are hydrogen atoms. Several R may mutually be same or different. )
The X in the general formula (1) or (1a) is a π-conjugated condensed ring having a structure represented by any one of the following general formulas (33) to (52). The fluorescent compound according to claim 1.

(In the general formulas (33) to (49), R represents a bonding site with Y in the general formula (1) or (1a). R may be the same or different from each other.
In the general formulas (50) to (52), L represents —CR 11 R 12 —, —O—, —NR 13 —, —SiR 14 R 15 —, or —S—. The plurality of L may be the same as or different from each other. R represents a binding site with Y in the general formula (1) or (1a). R 11 to R 15 each independently represent a hydrogen atom or a bonding site with Y in the general formula (1) or (1a). The plurality of R and R 11 to R 15 may be the same as or different from each other. )
6. The fluorescent compound according to claim 5, wherein all Rs in the general formulas (33) to (52) are groups having a structure represented by the general formula (2a).
6. The fluorescence according to claim 5, wherein one of R in the general formulas (33) to (52) is a triarylsilyl group, and the other Rs are all groups having the structure represented by the general formula (2a). Luminescent compound.
R 1 and R 5 in the general formula (2) or (2a) are represented by the general formula (3) or (4), respectively, and have different structures. The fluorescent compound according to any one of the above.
An organic material composition comprising the fluorescent compound according to any one of claims 1 to 8, and a phosphorescent compound or a thermally activated delayed fluorescent compound.
An organic material composition comprising the fluorescent compound according to any one of claims 1 to 8, a phosphorescent compound or a thermally activated delayed fluorescent compound, and a host compound.
A luminescent film containing the fluorescent compound according to any one of claims 1 to 8.
An organic electroluminescent element material containing a fluorescent compound having a structure represented by the following general formula (1).

(In the general formula (1), X represents a π-conjugated condensed ring having a 14π electron system or more. Y represents a deuterium atom, halogen atom, cyano group, nitro group, hydroxy group, mercapto group, alkyl group, cycloalkyl group. Group, alkenyl group, alkynyl group, heterocyclic group, alkoxy group, cycloalkoxy group, aryloxy group, alkylthio group, cycloalkylthio group, arylthio group, alkoxycarbonyl group, aryloxycarbonyl group, sulfamoyl group, acyl group, acyloxy group Amide group, carbamoyl group, ureido group, sulfinyl group, alkylsulfonyl group, arylsulfonyl group, heteroarylsulfonyl group, amino group, fluorinated hydrocarbon group, triarylsilyl group, diarylalkylsilyl group, aryldialkylsilyl group, Trialkylsilyl group, An acid ester group, a phosphite group, a phosphono group, a phenyl group, or a group having a structure represented by the following general formula (2) is represented, and these may further have a substituent. At least one is a group having a structure represented by the following general formula (2): Y may be the same as or different from each other when there are a plurality of Y. n is the π-conjugated condensation. Represents the number of Ys that can be substituted for hydrogen atoms on the ring, and represents an integer from 1 to the maximum number.)

(In the general formula (2), R 1 to R 5 are each independently a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a nitro group, a hydroxy group, a mercapto group, an alkyl group, a cycloalkyl group, or an alkenyl group. Alkynyl group, heterocyclic group, alkoxy group, cycloalkoxy group, aryloxy group, alkylthio group, cycloalkylthio group, arylthio group, alkoxycarbonyl group, aryloxycarbonyl group, sulfamoyl group, acyl group, acyloxy group, amide group, Carbamoyl group, ureido group, sulfinyl group, alkylsulfonyl group, arylsulfonyl group or heteroarylsulfonyl group, amino group, fluorinated hydrocarbon group, triarylsilyl group, diarylalkylsilyl group, aryldialkylsilyl group, trialkylsilyl group , Represents an ester group, a phosphite group, or a phosphono group, tables in at least one of these further may have a substituent .R 1 and R 5, the following general formula (3) or (4) * 1 represents a binding site with X.)

(In General Formula (3), A represents a carbon atom or a silicon atom. R 6 to R 8 each independently represents the same atom or substituent as R 1 to R 5 in General Formula (2). However, at least one of R 6 to R 8 is an alkyl group having 1 or more carbon atoms. * 2 represents a bonding site with an adjacent atom.)

(In General Formula (4), R 9 and R 10 each independently represent the same atom or substituent as R 1 to R 5 in General Formula (2), but at least one of them has 1 or more carbon atoms. * 3 represents a bonding site with an adjacent atom, R 1 to R 10 in the general formulas (2) to (4) are substituted or unsubstituted aliphatic groups bonded to each other. A ring may be formed, but an aromatic ring is not further condensed to the formed aliphatic ring.)
The organic electroluminescent element material according to claim 12, wherein at least one of R 1 and R 5 in the general formula (2) is represented by the general formula (3).
The organic electroluminescent element material according to claim 12 or 13, wherein the fluorescent compound having a structure represented by the general formula (1) has a structure represented by the following general formula (1a).

(In the general formula (1a), X represents a π-conjugated condensed ring having a 14π electron system or more. Y represents a deuterium atom, a triarylsilyl group, a diarylalkylsilyl group, an aryldialkylsilyl group, a trialkylsilyl group, A phenyl group or a group having a structure represented by the following general formula (2a), which may further have a substituent, wherein at least one of Y is represented by the following general formula (2a); Y may be the same or different when there are a plurality of groups, and n is the number of Ys that can be substituted for hydrogen atoms on the π-conjugated condensed ring. Represents an integer from 1 to the maximum number.)

(In the general formula (2a), R 1 to R 5 each independently represent the same atom or substituent as R 1 to R 5 in the general formula (2), but at least one of R 1 and R 5 Is a linear, branched or cyclic alkyl group having 2 or more carbon atoms, or at least one of R 1 and R 2 and R 4 and R 5 is bonded to each other to form a substituted or unsubstituted aliphatic ring. (The aromatic ring is not further condensed to the aliphatic ring formed at this time.)
The X in the general formula (1) or (1a) is a π-conjugated condensed ring having a structure represented by any of the following general formulas (5) to (21). The organic electroluminescence element material according to claim 1.

(In the general formulas (5) to (19), R represents a hydrogen atom or a bonding site with Y in the general formula (1) or (1a), but not all of them are hydrogen atoms. R may be the same as or different from each other.
In the general formulas (20) and (21), L represents —CR 11 R 12 —, —O—, —NR 13 —, —SiR 14 R 15 —, or —S—. The plurality of L may be the same as or different from each other. R and R 11 to R 15 each independently represent a hydrogen atom or a bonding site with Y in the general formula (1) or (1a), but not all are hydrogen atoms. Several R may mutually be same or different. )
The X in the general formula (1) or (1a) is a π-conjugated condensed ring having a structure represented by any one of the following general formulas (33) to (52). The organic electroluminescence element material according to claim 1.

(In the general formulas (33) to (49), R represents a bonding site with Y in the general formula (1) or (1a). R may be the same or different from each other.
In the general formulas (50) to (52), L represents —CR 11 R 12 —, —O—, —NR 13 —, —SiR 14 R 15 —, or —S—. The plurality of L may be the same as or different from each other. R represents a binding site with Y in the general formula (1) or (1a). R 11 to R 15 each independently represent a hydrogen atom or a bonding site with Y in the general formula (1) or (1a). The plurality of R and R 11 to R 15 may be the same as or different from each other. )
The organic electroluminescent element material according to claim 16, wherein all Rs in the general formulas (33) to (52) are groups having a structure represented by the general formula (2a).
The organic group according to claim 16, wherein one of R in the general formulas (33) to (52) is a triarylsilyl group, and the other Rs are all groups having the structure represented by the general formula (2a). Electroluminescence element material.
The R 1 and R 5 in the general formula (2) or (2a) are represented by the general formula (3) or (4), respectively, and have different structures. Organic electroluminescent element material as described in any one of these.
An organic electroluminescence device having an organic functional layer including at least a light emitting layer between an anode and a cathode,
The organic electroluminescent element in which the organic electroluminescent element material as described in any one of Claim 12 to 19 is contained in the said organic functional layer.