JPWO2018186462A1 - Fluorescent compound, organic material composition, luminescent film, organic electroluminescent device material, and organic electroluminescent device - Google Patents

Abstract

An object of the present invention is to provide a fluorescent compound that suppresses concentration quenching in a solid state. The fluorescent compound of the present invention has a structure represented by the following general formula (1). Embedded image

Description

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

  BACKGROUND ART 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 a “light-emitting material”) is sandwiched between an anode and a cathode. Are injected and recombined to generate excitons (excitons), and emit light by utilizing light emission (fluorescence / phosphorescence) when the excitons are deactivated. The organic EL element is capable of emitting light at a low voltage of several V to several tens of volts, and is a self-luminous type, so that it has a wide viewing angle, high visibility, and is a thin-film type solid-state element. For this reason, it has attracted attention from the viewpoint 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 where molecules are aggregated, they do not emit fluorescence due to concentration quenching and excimer formation, or they do not emit when in solution. Also tended to show long wavelength emission. Therefore, there is a problem in use in an organic EL device or bioimaging.

  For example, Patent Literature 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 to suppress 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 problems and circumstances, and a solution to the problem is to provide a fluorescent compound that suppresses concentration quenching in a solid state, an organic material composition, a luminescent film, an organic electroluminescent device material, and the like. An object of the present invention is to provide an organic electroluminescence device.

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

  That is, the above object 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 of 14π electron system or more. Y represents a deuterium atom, a halogen atom, a cyano group, a nitro group, a hydroxy group, a mercapto group, an alkyl group, a 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, heteroarylsulfonyl group, amino group, fluorinated hydrocarbon group, triarylsilyl group, diarylalkylsilyl group, aryldialkylsilyl group, Trialkylsilyl group, Represents a phosphate group, a phosphite group, a phosphono group, a phenyl group, or a group having a structure represented by the following general formula (2), and these may further have a substituent. At least one is a group having a structure represented by the following general formula (2): When there are a plurality of Y, they may be the same or different from each other; Represents the number of Y that can be substituted for a hydrogen atom on the ring, and represents an integer from 1 to the maximum number.)

(In the general formula (2), R ^{1 to} R ⁵ each independently represent 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, 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 to X.)

(In the general formula (3), A represents a carbon atom or a silicon atom. R ^{6 to} R ⁸ each independently represent the same atom or substituent as R ^{1 to} R ⁵ in the 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 the general formula (4), R ⁹ and R ¹⁰ each independently represent the same atom or substituent as R ^{1 to} R ⁵ in the general formula (2), and at least one has 1 or more carbon atoms. * 3 represents a bonding site to an adjacent atom, and R ^{1 to} R ¹⁰ in the general formulas (2) to (4) represent a substituted or unsubstituted aliphatic group in which adjacent groups are bonded to each other. A ring may be formed, but the formed aliphatic ring is not further condensed with an aromatic ring.)

2. 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. 3. The fluorescent compound according to item 1 or 2, wherein the 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 of 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: at least one of Y is represented by the following general formula (2a) When there are a plurality of Y's, they may be the same or different, and n is the number of Y's which 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 an atom or a substituent with R ^{1 to} R ⁵ in the general formula (2), and at least one of R ¹ and R ⁵ is a carbon atom. It is a linear, branched or cyclic alkyl group of two or more, or at least one of R ¹ and R ² and R ⁴ and R ⁵ are bonded to each other to form a substituted or unsubstituted aliphatic ring. The aromatic ring formed at this time does not further condense with the aromatic ring.)

  4. X in the above general formula (1) or (1a), wherein X is a π-conjugated condensed ring having a structure represented by any 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 to Y in the general formula (1) or (1a), but not all are hydrogen atoms. R may be the same or different from each other.
In the general formula (20) and (21), L ^{is, -CR 11 R 12 -, -} O -, - NR 13 -, - SiR 14 R 15 - or an -S-. A plurality of L may be the same or different from each other. R and R ^{11 to} R ¹⁵ each independently represent a hydrogen atom or a bonding site to Y in the general formula (1) or (1a), but not all are hydrogen atoms. A plurality of Rs may be the same or different from each other. )

  5. X in the above general formula (1) or (1a), wherein X is a π-conjugated condensed ring having a structure represented by any 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 to Y in the general formula (1) or (1a). Rs may be the same or different.
In the general formula (50) ~ (52), L ^{is, -CR 11 R 12 -, -} O -, - NR 13 -, - SiR 14 R 15 - or an -S-. A plurality of L may be the same or different from each other. R represents a bonding site to Y in the general formula (1) or (1a). R ^{11 to} R ¹⁵ each independently represent a hydrogen atom or a bonding site to Y in the general formula (1) or (1a). A plurality of R and R ^{11 to} R ¹⁵ may be the same or different from each other. )

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

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

8. Formula (2) or ^{R 1} and ^{R 5} in (2a), represented by each of the general formula (3) or (4), and, from the first term has a different structure to paragraph 7 The fluorescent compound according to any one of the above.

  9. 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. 9. 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 light-emitting film containing the fluorescent compound according to any one of Items 1 to 8.

  12. An organic electroluminescent device 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 of 14π electron system or more. Y represents a deuterium atom, a halogen atom, a cyano group, a nitro group, a hydroxy group, a mercapto group, an alkyl group, a 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, heteroarylsulfonyl group, amino group, fluorinated hydrocarbon group, triarylsilyl group, diarylalkylsilyl group, aryldialkylsilyl group, Trialkylsilyl group, Represents a phosphate group, a phosphite group, a phosphono group, a phenyl group, or a group having a structure represented by the following general formula (2), and these may further have a substituent. At least one is a group having a structure represented by the following general formula (2): When there are a plurality of Y, they may be the same or different from each other; Represents the number of Y that can be substituted for a hydrogen atom on the ring, and represents an integer from 1 to the maximum number.)

(In the general formula (2), R ^{1 to} R ⁵ each independently represent 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, 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 to X.)

(In the general formula (3), A represents a carbon atom or a silicon atom. R ^{6 to} R ⁸ each independently represent an atom or a substituent with R ^{1 to} R ⁵ in the general formula (2). 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 the general formula (4), R ⁹ and R ¹⁰ each independently represent the same atom or substituent as R ^{1 to} R ⁵ in the general formula (2), and at least one has 1 or more carbon atoms. * 3 represents a bonding site to an adjacent atom, and R ^{1 to} R ¹⁰ in the general formulas (2) to (4) represent a substituted or unsubstituted aliphatic group in which adjacent groups are bonded to each other. A ring may be formed, but the formed aliphatic ring is not further condensed with an aromatic ring.)

13. The organic electroluminescent device 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． 14. The organic electroluminescent 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 (1a), X represents a π-conjugated condensed ring of 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: at least one of Y is represented by the following general formula (2a) When there are a plurality of Y's, they may be the same or different, and n is the number of Y's which 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), and 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 are bonded to each other to form a substituted or unsubstituted aliphatic ring. The aromatic ring formed at this time does not further condense with the aromatic ring.)

  15. X in the general formula (1) or (1a) is any one of the twelfth to fourteenth aspects, wherein X is a π-conjugated fused ring having a structure represented by any of the following general formulas (5) to (21): 9. The organic electroluminescent device material according to claim 1.

(In the general formulas (5) to (19), R represents a hydrogen atom or a bonding site to Y in the general formula (1) or (1a), but not all are hydrogen atoms. R may be the same or different from each other.
In the general formula (20) and (21), L ^{is, -CR 11 R 12 -, -} O -, - NR 13 -, - SiR 14 R 15 - or an -S-. A plurality of L may be the same or different from each other. R and R ^{11 to} R ¹⁵ each independently represent a hydrogen atom or a bonding site to Y in the general formula (1) or (1a), but not all are hydrogen atoms. A plurality of Rs may be the same or different from each other. )

  16. X in the above general formula (1) or (1a), wherein X is a π-conjugated condensed ring having a structure represented by any of the following general formulas (33) to (52): 9. The organic electroluminescent device material according to claim 1.

(In the general formulas (33) to (49), R represents a bonding site to Y in the general formula (1) or (1a). Rs may be the same or different.
In the general formula (50) ~ (52), L ^{is, -CR 11 R 12 -, -} O -, - NR 13 -, - SiR 14 R 15 - or an -S-. A plurality of L may be the same or different from each other. R represents a bonding site to Y in the general formula (1) or (1a). R ^{11 to} R ¹⁵ each independently represent a hydrogen atom or a bonding site to Y in the general formula (1) or (1a). A plurality of R and R ^{11 to} R ¹⁵ may be the same or different from each other. )

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

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

19. Items 12 to 18 in which 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 organic electroluminescent element material according to any one of the above.

20. An organic electroluminescence device having an organic functional layer including at least a light emitting layer between the anode and the cathode,
20. An organic electroluminescence device, wherein the organic functional layer contains the organic electroluminescence device material according to any one of items 12 to 19.

  By the above means of the present invention, it is possible to provide a fluorescent compound, an organic material composition, a luminescent film, an organic electroluminescent device material, and an organic electroluminescent device which suppress concentration quenching in a solid state.

  Although the mechanism of manifestation and action of the effect of the present invention has not been clarified, it is speculated as follows.

  As a result of intensive studies, the present inventors have found that when a π-conjugated condensed ring of 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 by having a substituent having a height higher than that of an ethyl group, luminescence in a solution state can be maintained even in a solid state.

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

  ΔG = ΔH−TΔS (1)

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

To make ΔG a negative value or a smaller value, it is conceivable to reduce ΔH or increase ΔS.
In the related art, ΔG is controlled by introducing a group that becomes a steric hindrance to reduce intermolecular interaction and reduce 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 employing a benzene ring which is a non-fused aromatic hydrocarbon as a substituent (substituent Y in the general formula (1)) of the π-conjugated condensed ring, π is generated by steric repulsion between benzene rings between molecules. Intermolecular interaction between conjugated condensed rings can be reduced. That is, it can be considered that ΔG is reduced by reducing ΔH.
Note that, when the benzene ring has an aromatic substituent or is fused with another aromatic ring, the π plane is enlarged, so that the substitution or fused fused benzene ring has an intermolecular structure. It is considered that the contribution of the interaction increases and ΔH is not reduced as a whole. Therefore, the substituent Y of the π-conjugated condensed ring is preferably a benzene ring having no aromatic substituent, and is preferably a benzene ring not condensed with another aromatic ring.

Next, consider the contribution of ΔS. When at least one ortho position of the phenyl group is introduced with a substituent having a height higher than that of the ethyl group, the rotation of the bond between the π-conjugated condensed ring and the phenyl group is suppressed while the conformation of the substituent is ΔS can be increased by the presence of various conformers resulting from this.
For example, Japanese Patent No. 5557197 discloses a compound having a methyl group at the ortho position of a phenyl group. Although the rotation of the bond between the π-conjugated condensed ring and the phenyl group is suppressed by the steric hindrance of the methyl group, the methyl group cannot form a conformer, so that ΔS has little contribution to ΔG and ΔH has no contribution. It is considered only.
On the other hand, when a substituent having a height higher than that of an 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 due to the high degree of structural freedom due to the generation of countless conformations due to the rotation and vibration of the substituent.
Consider an ethyl group as an example. The carbon on the side closer to the phenyl group among the two carbon atoms of the ethyl group, that is, the methylene group (—CH ₂ —) suppresses 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, although the terminal methyl group can rotate freely, a relatively stable conformation occurs 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 antiperiplanar exist. In fact, the stability of this conformation depends on the degree of freedom of rotation, that is, the steric environment in which the ethyl group is located. It is possible to distinguish them. In any case, if the bulk is higher than the ethyl group, various conformations are generated, and their contribution can increase ΔS. In particular, in the present invention, it is considered that this increase in ΔS greatly contributes to reducing ΔG.

  As described above, employing a benzene ring as a substituent (reducing ΔH), and arranging a substituent having a height higher than that of an ethyl group in at least one ortho position of a phenyl group (increasing ΔS). Thus, it is presumed that luminescence in a solution state can be maintained even in a solid state.

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

  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 in particular, may be 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.

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

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

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

  The present invention can provide an organic material composition containing the above 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 above-mentioned fluorescent compound.

  The present invention can provide an organic electroluminescent device 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 embodiments and modes for carrying out the present invention will be described in detail. In the present application, “to” representing a numerical range is used to mean that the numerical values described before and after it are included as the lower limit and the upper limit.

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

  In the general formula (1), X represents a π-conjugated condensed ring of 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, cycloalkylthio, arylthio, alkoxycarbonyl, aryloxycarbonyl, sulfamoyl, acyl, acyloxy, amide, carbamoyl, ureido, sulfinyl, alkylsulfonyl, arylsulfonyl, heteroaryl Sulfonyl group, amino group, fluorinated hydrocarbon group, triarylsilyl group, diarylalkylsilyl group, aryldialkylsilyl group, trialkylsilyl group, phosphate group, phosphite 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 Y, they may be the same or different. n represents the number of Y that can be substituted for a 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. Those having the structure represented by 32) are preferable.

In the general formulas (5) to (19) and (22) to (32), R represents a hydrogen atom or a bonding site to Y in the general formula (1), but not all hydrogen atoms. A plurality of Rs may be the same or different from each other.
In the general formula (20) and (21), L ^{is, -CR 11 R 12 -, -} O -, - NR 13 -, - SiR 14 R 15 - or an -S-. A plurality of L may be the same or different from each other. R and R ^{11 to} R ¹⁵ each independently represent a hydrogen atom or a bonding site to Y in the general formula (1), but not all hydrogen atoms. A plurality of Rs may be the same or different from each other.

  Among them, 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 a film state, R ^{11 to} R ¹⁵ are a linear, branched or cyclic alkyl group, and any one of R is a general formula. It preferably has a group having the structure represented by (2).

Further, among the exemplified Xs, from the height of the fluorescence quantum yield, they are represented by the above general formulas (5), (7), (8), (13), (15) to (18) or (20). A π-conjugated condensed ring having a structure of
Further, from the viewpoint of maintaining the fluorescence quantum yield in a film state, those having a substitution form represented by the following general formulas (33) to (52) can be particularly preferably used.

In the general formulas (33) to (49), R represents a bonding site to Y in the general formula (1) or (1a). R may be the same or different from each other.
In the general formula (50) ~ (52), L ^{is, -CR 11 R 12 -, -} O -, - NR 13 -, - SiR 14 R 15 - or an -S-. A plurality of L may be the same or different from each other. R represents a bonding site to Y in the general formula (1) or (1a). R ^{11 to} R ¹⁵ each independently represent a hydrogen atom or a bonding site to Y in the general formula (1) or (1a). A plurality of R and R ^{11 to} R ¹⁵ may be the same or different from each other.

  As Y in the general formula (1), specifically, 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 groups (e.g., methoxy, ethoxy, propyloxy, Tyloxy 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 (E.g., methylthio, ethylthio, propylthio, pentylthio, hexylthio, octylthio, dodecylthio, etc.), cycloalkylthio (e.g., cyclopentylthio, cyclohexylthio, etc.), arylthio (e.g., phenylthio, Naphthylthio group, etc.), alkoxycarbonyl group (eg, methyloxycarbonyl group, ethyloxycarbonyl group, butyloxycarbonyl group, octyloxycarbonyl group, dodecyloxycarbonyl group, etc.), aryl Oxycarbonyl 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, 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, methylcarbonylamino group) Group, ethylcarbonylamino group, dimethylcarbonylamino group, propylcarbonylamino group, pentylcarbonylamino group, cyclohexylcarbonylamino group, 2-ethylhexylcarbonylamino group, octylcarbonylamino group, dodecylcarbonylamino group, phenylcarbonylamino group, naphthyl Carbonylamino group, etc.), carbamoyl group (for example, aminocarbonyl group, methylaminocarbonyl group, dimethylaminocarbonyl group, Nyl group, pentylaminocarbonyl group, cyclohexylaminocarbonyl group, octylaminocarbonyl group, 2-ethylhexylaminocarbonyl group, dodecylaminocarbonyl 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-pyridylaminoureide group, etc.), sulfinyl group (for example, methylsulfinyl group) , Ethylsulfinyl group, butylsulfinyl group, cyclohexylsulfinyl group, 2-ethylhexylsulfinyl group, dodecylsulfinyl group, phenylsulfinyl group , Naphthylsulfinyl, 2-pyridylsulfinyl, etc.), alkylsulfonyl (eg, methylsulfonyl, ethylsulfonyl, butylsulfonyl, cyclohexylsulfonyl, 2-ethylhexylsulfonyl, dodecylsulfonyl, etc.), aryl A sulfonyl group or a heteroarylsulfonyl group (eg, phenylsulfonyl group, naphthylsulfonyl group, 2-pyridylsulfonyl group, etc.), an 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, fluoride Hydrocarbon groups (eg, fluoromethyl group, trifluoromethyl group, pentafluoroethyl group, pentafluorophenyl group, etc.), triarylsilyl groups (eg, triphenylsilyl group, tri (4-methylphenyl) silyl group, (3,5-dimethylphenyl) silyl group, etc.), diarylalkylsilyl group (eg, t-butyldiphenylsilyl group, isopropyldiphenylsilyl group, etc.), aryldialkylsilyl group (eg, dimethylphenylsilyl group, isopropyldi (4 -Methylphenyl) silyl group, etc.), trialkylsilyl group (eg, trimethylsilyl group, triisopropylsilyl group, t-butyldimethylsilyl group, etc.), phosphate group (eg, dihexylphosphoryl group, etc.), phosphite ester Groups (eg diphenylphosphine) Alkylsulfonyl group), a phosphono group, a phenyl group, and the like. These substituents may be further substituted with the same substituents.

In the general formula (2), R ^{1 to} R ⁵ each independently represent 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, 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, 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 to X.

In the general formula (3), A represents a carbon atom or a silicon atom. R ^{6 to} R ⁸ each independently represent 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 the general formula (4), R ⁹ and R ¹⁰ each independently represent the same atom or substituent as R ^{1 to} R ⁵ in the general formula (2), and at least one is an alkyl having 1 or more carbon atoms. Group. * 3 represents a bonding site with an adjacent atom. In the general formulas (2) to (4), R ^{1 to} R ¹⁰ may be such that adjacent groups may be bonded to each other to form a substituted or unsubstituted aliphatic ring. The aromatic ring does not condense.

As 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), specifically, a hydrogen atom, a deuterium atom , A halogen atom (eg, 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 (eg, a methyl group, an ethyl group, a propyl group, an isopropyl group, a 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.), heterocyclic group (eg, pyrrolidyl group, imidazolidyl group, morpho group An alkoxy group (for example, a methoxy group, an ethoxy group, a propyloxy group, a pentyloxy group, a hexyloxy group, an octyloxy group, a dodecyloxy group), a cycloalkoxy group (for example, a 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.), Cycloalkylthio group (eg, cyclopentylthio group, cyclohexylthio group, etc.), arylthio group (eg, phenylthio group, naphthylthio group, etc.), alkoxycarbonyl group (eg, methyloxycarbonyl group, ethyloxycarbonyl Butyloxycarbonyl, octyloxycarbonyl, dodecyloxycarbonyl, etc.), aryloxycarbonyl (eg, phenyloxycarbonyl, naphthyloxycarbonyl, etc.), sulfamoyl (eg, aminosulfonyl, methylaminosulfonyl) Dimethylaminosulfonyl, butylaminosulfonyl, hexylaminosulfonyl, cyclohexylaminosulfonyl, octylaminosulfonyl, dodecylaminosulfonyl, phenylaminosulfonyl, naphthylaminosulfonyl, 2-pyridylaminosulfonyl, etc.), acyl Groups (eg, acetyl, ethylcarbonyl, propylcarbonyl, pentylcarbonyl, cyclohexylcarbonyl, octylcarbonyl, -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 (for example, 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 naphthylureide group) Group, 2-pyridylaminoureido group, etc.), sulfinyl group (for example, methylsulfinyl group, ethylsulfinyl group, butylsulfinyl group, cyclohexyl group) 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 Amino group, dimethylamino group, butylamino group, cyclopentylamino group, 2-ethylhexylamino group, dodecylamino group, anilino group, naphthylamino group, 2-pyridylamino , Piperidyl group (also called piperidinyl group), 2,2,6,6-tetramethylpiperidinyl group, etc., fluorinated hydrocarbon group (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 group (eg, dimethylphenylsilyl group, isopropyldi (4-methylphenyl) silyl group, etc.), trialkylsilyl group (eg, trimethylsilyl group, triisopropyl Silyl group, t-butyldimethylsilyl group, etc.), Examples include a phosphoric ester group (eg, a dihexyl phosphoryl group), a phosphite group (eg, a 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 a methyl group, an ethyl group, a propyl group, an isopropyl group, a tert-butyl group, a pentyl group, a hexyl group, an octyl group, a dodecyl group, and a tridecyl group. Group, tetradecyl group, pentadecyl group and the like.

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

At least one of R ¹ and R ⁵ in the general formula (2) is preferably represented by the general formula (3).
Further, it is preferable that R ¹ and R ⁵ in the general formula (2) are each represented by the general formula (3) or (4), and have different structures.

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

  In the general formula (1a), X represents a π-conjugated condensed ring of 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); Further, it 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 Y, they may be the same or different. n represents the number of Y that can be substituted for a hydrogen atom on the π-conjugated condensed ring, and represents an integer from 1 to the maximum number.

In Formula (2a), R ^{1 to} R ⁵ each independently represent the same atom or substituent as R ^{1 to} R ⁵ in Formula (2), but at least one of R ¹ and R ⁵ is carbon. It is a linear, branched or cyclic alkyl group of two or more, or at least one of R ¹ and R ² and R ⁴ and R ⁵ are bonded to each other to form a substituted or unsubstituted aliphatic ring. The aromatic ring formed at this time does not further condense with the aromatic ring.

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

  In the above general formulas (33) to (52), R is a group having a structure represented by the general formula (2a), or one of Rs is a triarylsilyl group, and the other R Is preferably a group 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 formula (2a-1), ring Z3 represents a substituted or unsubstituted aliphatic ring, but the aliphatic ring is not further condensed with an aromatic 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), and 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 to X.

In Formula (2a-2), Ring Z3 and Ring Z4 each represent a substituted or unsubstituted aliphatic ring, but the aromatic ring is not further condensed with the aliphatic ring. 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), and 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), and 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 represent 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 substitutable R ²³ in place of the hydrogen atoms on the ring Z4, represents an integer from 0 to the maximum number. * 1 represents a binding site to X.

In the 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), and 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), and 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 represent an integer of 0 to 2. * 1 represents a binding site to 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 include a ring Z1 and a ring Z2 in the general formula (DP) described later. And the same substituents as those described above.

  Hereinafter, exemplary compounds of the fluorescent compound of the present invention are shown, but are not limited thereto.

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

<Synthesis of Exemplified Compound 6>
Perylene tetraboronic acid pinacol ester (3.0 g), triisopropylbromobenzene (6.1 g), and potassium phosphate (13 g) were placed in a reaction vessel, and the system was purged with nitrogen. After adding 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 the mixture was stirred for 4 hours under reflux with heating. After allowing the reaction mixture to cool, extraction with toluene and washing with a saturated saline solution were performed. The crude product was purified by column chromatography to obtain Exemplified Compound 6 (1.16 g, yield: 28%).
The obtained product was measured by ESI-MS, and identified as Exemplified Compound 6 (molecular weight: 1061.7, detected value: 1062).

<Synthesis of Exemplified Compound 34>
(Synthesis of Intermediate 1)
In a reaction vessel, under a nitrogen atmosphere, [Ir (OMe) (cod)] ₂ (cod = 1,5-cyclooctadiene, 0.15 g), 4,4′-di-tert-butyl-2,2′- 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 the mixture was stirred at 40 ° C. Subsequently, Chem. Commun. , Vol. 52, p. 1124, and planarized 9-phenylanthracene (1.0 g) synthesized with reference to 2016, and the mixture was stirred at 60 ° C. for 8 hours. After allowing to cool, the mixture was purified 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 placed 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) and stirred for 4 hours under heated reflux. After allowing the reaction mixture to cool, extraction with toluene and washing with a saturated saline solution were performed. 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 placed 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 the mixture was stirred, followed by extraction with dichloromethane and washing with saturated saline. The crude product was purified by column chromatography to obtain Intermediate 3 (0.81 g, yield: 92%).

(Synthesis of Exemplified Compound 34)
Intermediate 3 (0.81 g), phenylboronic acid (0.20 g), and potassium carbonate (0.33 g) were placed in a reaction vessel, and 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 under heated reflux for 4 hours. After allowing the reaction mixture to cool, extraction with toluene and washing with a saturated saline solution were performed. The crude product was purified by column chromatography to obtain Exemplified Compound 34 (0.63 g, yield: 78%).
The obtained product was measured by ESI-MS, and identified as Exemplified Compound 34 (molecular weight: 1017.6, detection value: 1018).

《Luminescent 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 light emitting materials. The light emitting material may contain other components as necessary, in addition to the π-conjugated compound. 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 is characterized by containing a fluorescent compound having the structure represented by the general formula (1) and a phosphorescent compound or a thermally activated delayed fluorescent compound. I do. Further, 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.
Preferably, it is a phosphorescent compound having a structure represented by the following general formula (DP). By using the phosphorescent compound, not only the exciton can be further 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) can be improved. Can be increased, and as a result, the exciton can be more effectively used for light emission, and as a result, the lifetime of the element can be further extended.

In the 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, a substituted or unsubstituted 5- or 6-membered aromatic heterocyclic ring formed with A ¹ and A ² , or any of these rings. Represents an aromatic fused ring containing at least one of the following. 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. The carbon atoms in the ring Z1 and the ring Z2 may be carbene carbon atoms. ^One of the bond between A ¹ and M and the bond between B ¹ and M represents a coordination bond, and the other represents a covalent bond. At this time, the condensed ring structure may be formed by bonding the substituents of the ring Z1 and the ring Z2. Further, the ligands represented by two or three rings Z1 and Z2 may be directly connected to each other or via a linker portion (connecting group) in the ring Z1 or the ring Z2. L represents a monoanionic bidentate ligand coordinated to M, and may have a substituent. m represents an integer of 0 to 2. n represents an integer of 1 to 3. When M is Ir, m + n is 3, and when M is Pt, m + n is 2. When m or n is 2 or more, the ligands represented by the plurality of rings Z1 and the plurality of rings Z or the plurality of Ls may be the same or different from each other. The ligand represented by the ring Z1 and the ring Z2 may be linked to L.

  Examples of the substituent which the ring Z1 and the ring Z2 may have include an alkyl group (for example, a methyl group, an ethyl group, a propyl group, an isopropyl group, a tert-butyl group, a pentyl group, a hexyl group, an octyl group, a 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 groups (also referred to as aromatic carbocyclic groups, aryl groups, etc., for example, phenyl, p-chlorophenyl, mesityl, tolyl, xylyl, naphthyl, anthryl, azulenyl, acenaphthenyl) , Fluorenyl group, phenanthryl group, indenyl group, pyrenyl group, biphenylyl group ), Aromatic heterocyclic groups (e.g., furyl, thienyl, pyridyl, pyridazinyl, pyrimidinyl, pyrazinyl, triazinyl, imidazolyl, pyrazolyl, thiazolyl, quinazolinyl, carbazolyl, carbolinyl, dia Zacarbazolyl group (showing one in which one of the carbon atoms constituting the carboline ring of the carbolinyl group is replaced by a nitrogen atom), phthalazinyl group, etc.), heterocyclic group (for example, pyrrolidyl group, imidazolidyl group, morpholyl) Group, oxazolidyl group, etc.), alkoxy group (for example, methoxy group, ethoxy group, propyloxy group, pentyloxy group, hexyloxy group, octyloxy group, dodecyloxy group, etc.), cycloalkoxy group (for example, cyclopentyloxy group, Cyclohexyloxy group, etc.) Oxy 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.), cycloalkylthio group (eg, cyclopentylthio group) Group, cyclohexylthio group, etc.), arylthio group (eg, phenylthio group, naphthylthio group, etc.), alkoxycarbonyl group (eg, methyloxycarbonyl group, ethyloxycarbonyl group, butyloxycarbonyl group, octyloxycarbonyl group, dodecyloxycarbonyl Group), an aryloxycarbonyl group (eg, phenyloxycarbonyl group, naphthyloxycarbonyl group, etc.), a 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, 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 groups (eg, acetyloxy group, ethylcarbonyloxy group, butylcarbonyloxy group, octylcarbonyloxy group, dodecyl Rubornyloxy 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, dodecylaminocar Enyl 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, cycloalkyl) Rohexylsulfonyl 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), , 2,6,6-tetramethylpiperidinyl group, etc.), halogen atom (eg, fluorine atom, chlorine atom, bromine atom, etc.), fluorinated hydrocarbon group (eg, fluoromethyl group, trifluoromethyl group, pentane Fluoroethyl group, pentafluoro Phenyl group), cyano group, nitro group, hydroxy group, mercapto group, silyl group (eg, trimethylsilyl group, triisopropylsilyl group, triphenylsilyl group, phenyldiethylsilyl group, etc.), phosphate group (eg, dihexyl) A phosphoryl group), a phosphite group (eg, a diphenylphosphinyl group), a phosphono group, and the like.

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

Ring Z2 is preferably a 5-membered aromatic heterocyclic ring, it is preferred that at least one of B ¹ and B ² is 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 the general formula (DP-1), M, A ¹ , A ² , B ¹ , B ² , the ring Z1, L, m, and n represent M, A ¹ , A ² , B ¹ , It has the same meaning as B ² , ring Z1, L, m and n.

B ^{3 to} B ⁵ are each a group of atoms forming an aromatic heterocyclic ring, and each independently represents a carbon atom, a nitrogen atom, an oxygen atom or a 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 the ring Z2 may have in the general formula (DP).

In the general formula (DP-1), the aromatic heterocyclic ring formed by B ^{1 to} B ⁵ is represented by any of the following general formulas (DP-1a), (DP-1b) and (DP-1c) It preferably has a structure.

Formula (DP-1a), in (DP-1b) and (DP-1c), * 4 represents a binding site to ^{A 2} in the general formula (DP-1). * 5 represents a binding site to M.
Rb ³ ~Rb ⁵ represents a hydrogen atom or a substituent. As the substituent represented by Rb ³ ~Rb ^5, ring Z1 and the ring Z2 is identical group and the substituent which may have the general formula (DP).
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. B ³ .about.B ⁵ is preferably at least one 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 preferably have 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 further preferably the aromatic ring is any one of a benzimidazole ring, an imidazopyridine ring, an imidazopyrazine ring and a purine ring.
Rb ⁵ is preferably an alkyl group or an aryl group, and more preferably a phenyl group.

  Examples of the phosphorescent compound having a structure represented by the general formula (DP) are shown below, but the invention is not limited thereto.

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

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), WO 2009/100991, WO 2008/101842, WO 2003/040257, U.S. Patent Application Publication No. 2006/835469, U.S. Patent Application Publication 2006/2006. No. 0202194, U.S. Patent Application Publication No. 2007/0087321, U.S. Patent Application Publication No. 2005/02444673, 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), WO 2009/050290, WO 2002/015645, WO 2009/000673, U.S. Patent Application Publication No. 2002/0034656, U.S. Patent No. 7,332,232 U.S. Patent Application Publication No. 2009/0108737, U.S. Patent Application Publication No. 2009/0039776, U.S. Patent No. 6,921,915, U.S. Patent No. 6,687,266, U.S. Patent Application Publication No. 2007/0190359. Specification, U.S. Patent Application Publication No. 2006/0008670, U.S. Patent Application Publication No. 2009/0165846, U.S. Patent Application Publication No. 2008/0015355, U.S. Patent No. 7,250,226, U.S. 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. 2005/0193373, International Publication No. 2005/123873, International Publication No. 2005/123873, WO 2007/004380, WO 2006/082742, U.S. Patent Application Publication No. 2006/0251923, U.S. Patent Application Publication No. 2005/0260441, U.S. Patent No. 7393599. Specification, U.S. Patent No. 7,534,505, U.S. Patent No. 7,445,855, U.S. Patent Application Publication No. 2007/0190359, U.S. Patent Application Publication No. 2008/0297033, U.S. Patent No. 7,338,722 , US special Patent Application Publication No. 2002/0134984, U.S. Patent 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, WO 2010/032663, WO 2008/140115, WO 2007/052431, WO 2011/134013, WO 2011/157339, WO 2010/086089, WO 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. 2012/228584, USA Patent Application Publication No. 2012/212126, JP-A-2012-069737, JP-A-2012-195554, JP-A-2009-114086, JP-A-2003-81988, JP-A-2002-302671 And JP-A-2002-363552.
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, WO2005 / 0193373, WO2006 / 056418, The carbene complexes described in WO 2005/113704, WO 2007/115970, WO 2007/115981, and WO 2008/000727 can be suitably used.

<Heat-activated delayed fluorescent compound>
The heat-activated delayed fluorescent compound according to the present invention utilizes a phenomenon in which reverse intersystem crossing from triplet exciton to singlet exciton (Reverse Intersystem Crossing: hereinafter, abbreviated as “RISC” as appropriate). There is no particular limitation as long as fluorescence emission using a phenomenon (thermally activated delayed fluorescence (also referred to as “thermally excited delayed fluorescence”: Thermally Activated Delayed Fluorescence: hereinafter abbreviated as “TADF” as appropriate)) is observed.

  Hereinafter, exemplary compounds of the heat-activated delayed fluorescent compound will be described, but the present invention is not limited thereto.

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

Known heat-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-A-2013-116975, Nature, 2012, 492, 234, Nature, Photonics, 2014, 8, 326, Adv. Mater. 2014, 26, 7931 can be suitably 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.
Hereinafter, the host compound according to the present invention will be described.

  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 device or the like, it is possible to adjust the transfer of electric charges, and high efficiency can be realized.

  There is no particular limitation on the host compound according to the present invention, and for example, compounds conventionally used in organic EL devices 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 It represents a group having a structure represented by the following general formula (HC), and in at least one of the groups having a structure represented by the following general formula (HC), Ar represents a carbazolyl group.

General formula (HC)
Ar- (L ') n- *

  In the general formula (HC), L ′ represents a divalent linking group derived from an aromatic hydrocarbon ring or an aromatic heterocycle. n represents an integer of 0 to 3, and when n is 2 or more, a plurality of L's may be the same or different. * Represents a binding site to 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 represent C (R ″) or N, and R ′ and R ″ represent a hydrogen atom, a substituent or a bonding site to L ′ in the general formula (HC). * Represents a binding site to L ′ in the general formula (HC).

  In the compound having a 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.

  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-mentioned general formula (DP) )) And the same substituents as the rings Z1 and 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 the carbon atoms constituting the carboline ring is replaced by a nitrogen atom), and a phthalazine ring.

  Hereinafter, as specific examples of the host compound according to the present invention, in addition to the compound having the structure represented by the above general formula (HA) or (HB), compounds applicable to the present invention are listed. Is not particularly limited.

  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, JP-A-2002-308855, JP-A-2001-313179, JP-A-2002-319492, JP-A-2001-357977, JP-A-2002-334786, JP-A-2002-8860, JP-A-2002-334787, JP-A-2002-15871, JP-A-2002-334788, JP-A-2002-43056, JP-A-2002-334789, JP-A-2002-75645, JP-A-2002-338579, and JP-A-2002-338579. JP-A-2002-105445, JP-A-2002-343568, JP-A-2002-141173, JP-A-2002-352957, JP-A-2002-203683, JP-A-2002-363227, JP-A-2002-231453, and JP-A-2002-231453. No. 003-3165, No. 2002-234888, No. 2003-27048, No. 2002-255934, No. 2002-260861, No. 2002-280183, No. 2002-299060, No. 2002 JP-A-302516, JP-A-2002-305083, JP-A-2002-305084, JP-A-2002-308837, U.S. Patent Application Publication No. 2003/0175555, U.S. Patent Application Publication No. 2006/0280965, U.S. Patent Application Publication No. 2005/0112407, U.S. Patent Application Publication No. 2009/0017330, U.S. Patent Application Publication No. 2009/0030202, U.S. Patent Application Publication No. 2005/0238919, International Publication No. 001/039234, WO 2009/021126, WO 2008/056746, WO 2004/093207, WO 2005/089025, WO 2007/063796, WO 2007/063796. WO63 / 75482, WO2004 / 107822, WO2005 / 030900, WO2006 / 114966, WO2009 / 086028, WO2009 / 003898, WO2012 / 023947. JP-A-2008-074939, JP-A-2007-254297, and EP2034538. Furthermore, compounds H-1 to H-230 described in paragraphs [0255] to [0293] of JP-A-2015-38941 can also be suitably used.

As described above, the fluorescent compound, the phosphorescent compound or the heat-activated delayed fluorescent compound, and the host compound contained in the organic material composition of the present invention have been described separately. It may be a combination of an activated delayed fluorescent compound and a host compound.
In addition, a plurality of the above-mentioned phosphorescent compounds or heat-activated delayed fluorescent compounds may be used in combination, and a plurality of the above-mentioned host compounds may be used in combination.

<< Organic EL device >>
The fluorescent compound having the structure represented by the general formula (1) of the present invention can be used for 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. It is contained.

<Constituent layer of organic EL element>
Representative device configurations in the organic EL device of the present invention include the following configurations (1) to (7), 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 / emission layer / electron transport layer / electron injection layer / cathode (6) anode / hole injection layer / hole transport layer / emission 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-described typical device configuration, a layer excluding the anode and the cathode is called 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, and when there are a plurality of light emitting layers, a non-light emitting intermediate layer may be provided between each light emitting layer.
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, respectively. 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) and a hole injection layer (also referred to as an anode buffer layer) may be provided between them.

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

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

  As a typical element configuration of the tandem structure, for example, the following configuration can be given.

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. Also, two light emitting units may be the same, and the other one may be different.

  Further, the third light emitting unit may not be provided, and 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 stacked directly or may be stacked via an intermediate layer.
The intermediate layer is generally referred to as an intermediate electrode, an intermediate conductive layer, a charge generation layer, an electron extraction layer, a connection layer, or an intermediate insulating layer. Electrons are provided in an adjacent layer on the anode side, and holes are provided in an adjacent layer on the cathode side. A known material configuration can be used as long as the layer has a function of supplying the material.

As a material used for the intermediate layer, for example, 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 or the like multilayer film _also, fullerenes such as _{C 60,} conductive such as oligothiophene Organic layers, conductive organic compound layers such as metal phthalocyanines, metal-free phthalocyanines, metal porphyrins, and metal-free porphyrins, and the like. The present invention is not limited thereto.

  Preferred configurations in the light-emitting unit include, for example, the configurations (1) to (7) described in the above-described typical device configurations, except that the anode and the cathode are excluded, but the present invention is not limited thereto. Not done.

  Specific examples of the tandem type organic EL device 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. Patent No. 6,337,492, International Publication No. 2005/009087, JP-A-2006-228712, JP-A-2006-24791, JP-A-2006-49393, and JP-A-2006-49394. JP-A-2006-49396, JP-A-2011-96679, JP-A-2005-340187, JP-A-47111424, JP-A-3496681, JP-A-38884564, JP-A-42131169, JP 2010-192719 A, JP Nos. 009-076929, JP-A-2008-078414, JP-A-2007-059848, JP-A-2003-272860, JP-A-2003-045676, and International Publication No. 2005/094130. Although a configuration and a constituent material are exemplified, the present invention is not limited to these.

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

<Light-emitting layer>
The light emitting layer according to the present invention provides a field where electrons and holes injected from an electrode or an adjacent layer (hereinafter, also referred to as “adjacent layer”) recombine and emit light via excitons. The layer that emits light may be inside the layer of the light emitting layer or at the interface between the light emitting layer and an adjacent layer.

  There is no particular limitation on the total thickness of the light emitting layer, but the uniformity of the film to be formed, the prevention of applying an unnecessary high voltage at the time of light emission, and the improvement of the stability of the emission color with respect to the driving current are improved. 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 still 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 a range of 2 nm to 1 μm, more preferably adjusted within a range of 2 to 200 nm, and still more preferably set within a range of 3 to 150 nm. Will be adjusted within.

(Light emitting 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 Is a more preferred embodiment.
Further, 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) Light-Emitting Dopant It is preferable to use a phosphorescent compound (also referred to as a phosphorescent dopant or a phosphorescent compound) and a fluorescent compound (a fluorescent dopant or a fluorescent compound) in combination.

  In the present invention, a plurality of phosphorescent compounds may be used in combination, or a combination of dopants having different structures may be used. Thereby, an arbitrary luminescent color can be obtained.

  The emission color of 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 Color Society of Japan, published by The University of Tokyo, 1985), and is shown in FIG. It is determined by the color when the result measured by Minolta Co., Ltd. is applied to the CIE chromaticity coordinates.

In the present invention, it is also preferable that one or more light-emitting layers contain a plurality of light-emitting dopants having different emission colors and emit white light.
There is no particular limitation on the combination of the light-emitting dopant that exhibits white, and examples thereof include a combination of blue and orange, 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 closer to orange or white closer to blue. However, when the 2 ° viewing angle front luminance is measured by the above method. In addition, it is preferable that the chromaticity in the CIE1931 color system at 1000 cd / m ^{2 be} in the range 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, and specifically, a compound that emits phosphorescence at room temperature (25 ° C.). The compound is defined as a compound having a phosphorescence quantum yield of 0.01 or more at 25 ° C., and a 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 Spectroscopy II, pp. 398 (1992 edition, Maruzen) of the fourth edition of Experimental Chemistry Lecture 7. Although the phosphorescence quantum yield in a solution can be measured using various solvents, in the present invention, the phosphorescent compound achieves the above-mentioned phosphorescence quantum yield (0.01 or more) in any of the solvents. It should be done.

There are two types of light emission principles of phosphorescent compounds. One is that the recombination of carriers occurs on the host compound where the carriers are transported, and the excited state of the host compound is generated. This is an energy transfer type in which light is emitted from a phosphorescent compound by being transferred to a compound.
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, so that light emission from the phosphorescent compound is obtained.
In either 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 a light emitting layer of an organic EL device. Specific examples include a phosphorescent compound having a structure represented by the general formula (DP) described above, a known phosphorescent compound described in the above-cited literature, and the like.
Among them, preferred phosphorescent compounds include organometallic complexes having Ir as a central metal. More preferably, a complex containing at least one coordination mode among a metal-carbon bond, a metal-nitrogen bond, a metal-oxygen bond, and a 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 another fluorescent compound different from this. 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 emission from singlet excitation is observed.

  Other fluorescent compounds include, for example, 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, squarium 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 also 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, JP-A-2011-213643, and JP-A-2010-93181. 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 substantially no light emission of itself is observed in the organic EL device.

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

  Further, 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 transfer of charges, and the efficiency of the organic EL device can be increased.

  There is no particular limitation on the host compound, and compounds used in conventional organic EL devices 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, it has a hole-transporting ability or an electron-transporting ability, prevents a long wavelength of light emission, and furthermore, stabilizes the organic EL element against heat generation during high-temperature driving or element driving. From the viewpoint of operating at high temperature, it is preferable to have a high glass transition temperature (Tg). Preferably, Tg is 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).

  As the known host compound used in the organic EL device of the present invention, those similar to the host compound in the above-described organic material composition can be exemplified.

  Further, 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 may be made of a material having a function of transporting electrons, and may 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.

  In the case of an organic EL device, when light generated in a light emitting layer is extracted from an electrode, light extracted directly from the light emitting layer interferes with light extracted after being reflected by an electrode for extracting light and an electrode located on a counter electrode. It is known to cause When light is reflected by the cathode, the interference effect can be efficiently used 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 have any of an electron injecting or transporting property and a hole blocking property, and may be any of conventionally known compounds. Can be selected and used.

  For example, nitrogen-containing aromatic heterocyclic derivatives (carbazole derivatives, azacarbazole derivatives (where 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, benzothiazole derivatives, etc.), dibenzofuran derivatives, Examples include dibenzothiophene derivatives, silole derivatives, aromatic hydrocarbon ring derivatives (naphthalene derivatives, anthracene derivatives, triphenylene, etc.).

In addition, metal complexes having a quinolinol skeleton or a dibenzoquinolinol skeleton as a ligand, for example, 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), and metal complexes thereof Can also be used as the electron transporting material in which the central metal of the above is replaced by In, Mg, Cu, Ca, Sn, Ga or Pb.

  In addition, metal-free or metal phthalocyanine, or those whose terminals are substituted with an alkyl group, a sulfonic acid group, or the like can be preferably used as the electron transporting material. Also, a distyrylpyrazine derivative can be used as an electron transporting material, and inorganic semiconductors such as n-type Si and n-type SiC as well as a hole injection layer and a hole transporting layer can be used as an electron transporting material. Can be.

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

  In the electron transport layer, a doping material may be doped as a guest material in the electron transport layer 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 compounds such as metal complexes and metal halides. Specific examples of the electron transport layer having such a configuration include, for example, JP-A-4-297076, JP-A-10-270172, JP-A-2000-196140, JP-A-2001-102175, and J.P. Appl. Phys. , 95, 5773 (2004).

  Specific examples of known and preferred 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.

  U.S. Patent No. 6,528,187, U.S. Patent No. 7,230,107, U.S. Patent Application Publication No. 2005/0025993, U.S. Patent Application Publication No. 2004/0036077, U.S. Patent Application Publication No. 2009/0115316 US Patent Application Publication No. 2009/0101870, US Patent Application Publication No. 2009/0179554, International Publication No. 2003/060956, International Publication No. 2008/132805, 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. 7,964,293, U.S. Patent Application Publication No. 2009/030202, International Publication No. 2004/080975, International Publication No. 2004/063159, International Publication No. 2005/085387. WO 2006/067931, WO 2007/086552, WO 2008/114690, WO 2009/069442, WO 2009/066779, WO 2009/054253, International WO 2011/086935, WO 2010/150593, WO 2010/047707, EP 231826, JP 2010-251675, JP 2009-209133, JP 2009 −1241 4, JP-A-2008-277810, JP-A-2006-156445, JP-A-2005-340122, JP-A-2003-45662, JP-A-2003-31367, and JP-A-2003-282270. Gazette, WO 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 transporting layer in a broad sense, and is preferably made of a material having a function of transporting electrons and having a small ability to transport holes. , The probability of recombination of electrons and holes can be improved.

  Further, the above-described structure 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 light emitting layer on the cathode side.

  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 described above is preferably used, and the material used for the host compound described above 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 for lowering driving voltage and improving light emission luminance. 2nd Chapter, Chapter 2, "Electrode Materials" (Nov. 30, 1998, published by NTTS)) (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 its thickness is preferably in the range of 0.1 to 5 nm, depending on the material. Further, the film may be a non-uniform film in which the constituent material is present intermittently.

  The details of the electron injection layer are also described in JP-A-6-325871, JP-A-9-17574, and JP-A-10-74586. Specific examples of materials preferably used for the electron injection layer include: , Metals such as strontium and aluminum, alkali metal compounds such as lithium fluoride, sodium fluoride, and potassium fluoride; alkaline earth metal compounds such as magnesium fluoride and calcium fluoride; Examples include metal oxides represented by aluminum, metal complexes represented by lithium 8-hydroxyquinolate (Liq), and the like. Further, the above-described electron transport materials can be used.

  The material 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.

  The material used for the hole transporting layer (hereinafter, referred to as a hole transporting material) may have any of a hole injecting or transporting property and an electron barrier property. Any one can be selected from 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, polyvinylcarbazole, polymer materials or oligomers having aromatic amines introduced into the main chain or side chain, polysilane, conductive Polymer or oligomer (for example, PEDOT: PSS, aniline-based copolymer, polyaniline, polythiophene, etc.).

  Examples of the triarylamine derivative include a benzidine type represented by α-NPD, a star burst type represented by MTDATA, and a compound having fluorene or anthracene in a triarylamine-linked core portion.

  Further, a hexaazatriphenylene derivative described in JP-T-2003-519432, JP-A-2006-135145, or the like can also be used as a hole transport material.

  Further, a highly p-type hole transporting layer doped with impurities can be used. Examples thereof include JP-A-4-297076, JP-A-2000-196140, JP-A-2001-102175, and J.P. Appl. Phys. , 95, 5773 (2004).

Also, JP-A-11-251067, J.P. Huang et. al. A so-called p-type hole transporting material or an inorganic compound such as p-type-Si or p-type-SiC as described in a written reference (Applied Physics Letters 80 (2002), p. 139) can also be used. Further, an orthometalated organometallic complex having Ir or Pt as a central metal, such as Ir (ppy) ₃ , is also preferably used.

  As the hole transporting material, those described above can be used, but a triarylamine derivative, a carbazole derivative, an indolocarbazole derivative, an azatriphenylene derivative, an organometallic complex, or an aromatic amine is introduced into a main chain or a side chain. Polymer materials or oligomers are preferably used.

  Specific examples of known preferable hole transporting materials used for 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 above-mentioned documents.

  For example, Appl. Phys. Lett. 69, 2160 (1996); 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); 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. 2006/02420279, U.S. Patent Application Publication No. 2008 / No. 0220265, U.S. Pat. No. 5,061,569, International Publication No. 2007/002683, International Publication No. 2009/018809, European Patent No. 6509555, U.S. Patent Application Publication No. 2008/0124572, U.S. 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, JP-T-2003-519432, Open 2006-135 45 No. is US Patent Application No. 13/585981 Patent like.

  The hole transporting 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 having a small ability to transport electrons. , The probability of recombination of electrons and holes can be improved.

  In addition, the above-described structure of the hole transport layer can be used as an electron blocking layer, if necessary.

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

  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 above-described hole transporting layer is preferably used, and the material used for the above host compound is also preferably used for the electron blocking layer.

<Hole injection layer>
A hole injection layer (also referred to as an “anode buffer layer”) is a layer provided between an anode and a light-emitting layer for lowering driving voltage and improving light emission luminance. (Nov. 30, 1998, published by NTT Corporation) ", Vol. 2, Chapter 2," Electrode Materials "(pages 123 to 166).

  In the present invention, the hole injection layer may be provided as needed, 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 also described in JP-A-9-45479, JP-A-9-260062, JP-A-8-288069, and the like. As a material used for the hole injection layer, for example, And the materials used for the above-described hole transport layer.

  Above all, phthalocyanine derivatives represented by copper phthalocyanine, hexaazatriphenylene derivatives described in JP-T-2003-519432 and JP-A-2006-135145, metal oxides represented by vanadium oxide, amorphous Carbon, conductive polymers such as polyaniline (emeraldine) and polythiophene, ortho-metalated 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.

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

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

  The content of the content can be arbitrarily determined, but is preferably 1000 ppm or less, more preferably 500 ppm or less, and still more preferably 50 ppm or less based on 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, the purpose of making the energy transfer of excitons advantageous, and the like.

<Method of 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 adopted.
Hereinafter, a method of forming an organic functional layer (a hole injection layer, a hole transport layer, an electron blocking layer, a light emitting layer, a hole blocking layer, an electron transport layer, an electron injection layer, and the like) will be described.

  The method for forming the organic functional layer according to the present invention is not particularly limited. For example, a vacuum deposition method such as a dry process, a formation method using a wet process, or the like can be used. A method may be used in which an organic functional layer is formed by laminating a wet process or a dry process in accordance with the material and selectively stacking the layers. Here, it is preferable that the organic functional layer is a layer formed by a wet process. That is, it is preferable to manufacture an organic EL element by a wet process. By manufacturing an organic EL element by a wet process, it is possible to obtain effects such as easy formation of a uniform film (coating) and generation of pinholes. Here, the film (coating film) is a film that has been dried after being applied by a wet process.

  Examples of the wet process include a spin coating method, a casting method, an inkjet method, a printing method, a die coating method, a blade coating method, a roll coating method, a spray coating method, a curtain coating method, an LB method (Langmuir-Blodgett method), and the like. From the viewpoint of easily obtaining a uniform thin film and high productivity, a method having high suitability for a roll-to-roll method 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 an evaporation method (resistance heating, an EB method, and the like), a sputtering method, a CVD method, and the like.

  In the present invention, as a liquid medium for dissolving or dispersing the organic EL element material constituting each layer, for example, methyl ethyl ketone, ketones such as 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.

  In addition, as a dispersing method, dispersing can be performed by a dispersing method such as ultrasonic wave, high shearing force dispersion, and media dispersion.

Further, a different film formation method may be applied to each layer. When a vapor deposition method is used for film formation, the vapor deposition conditions vary depending on the type of the compound used, etc., 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 appropriately select 0.01 to 50 nm / sec, a substrate temperature of -50 to 300 ° C., and a thickness of 0.1 nm to 5 μm, preferably 5 to 200 nm.

  The organic functional layer according to the present invention is preferably formed from the hole injection layer to the cathode consistently by a single evacuation, but may be taken out in the middle and subjected to a different film formation method. In that case, it is preferable to perform the operation in a dry inert gas atmosphere.

<anode>
As the anode in the organic EL device, a material having a large work function (4 eV or more, preferably 4.5 eV or more), a metal, an alloy, an electrically conductive compound, or a mixture thereof as an electrode material 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, a material such as IDIXO (In ₂ O ₃ —ZnO) that can form an amorphous and transparent conductive film may be used.

  The anode may form a thin film by a method such as vapor deposition or sputtering of these electrode substances and form a pattern of a desired shape by a photolithography method, or when a pattern precision is not required so much (about 100 μm or more). ), A pattern may be formed through a mask having a desired shape at the time of vapor deposition or sputtering of an electrode material.

  Alternatively, when a substance that can be applied such as an organic conductive compound is used, a wet film formation method such as a printing method and a coating method can be used. When light emission is extracted from this anode, it is desirable to make the light transmittance 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 in the range of 10 nm to 1 μm, preferably in the range of 10 to 200 nm.

<cathode>
As the cathode, a material having a low work function (4 eV or less) metal (referred to as an electron injecting metal), an alloy, an electrically conductive compound, and a mixture thereof is used. Specific examples of such an electrode material 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 them, a mixture of an electron-injecting metal and a second metal that is a stable metal having a large work function value, such as a magnesium / silver mixture, from the viewpoint of durability against electron injection and oxidation. Preferred are a magnesium / aluminum mixture, a magnesium / indium mixture, an aluminum / aluminum oxide (Al ₂ O ₃ ) mixture, a lithium / aluminum mixture, aluminum and the like.

  The cathode can be manufactured by forming a thin film from these electrode substances by a method such as evaporation or sputtering. The sheet resistance as a cathode is several hundred Ω / sq. The following is preferred, and the thickness is usually selected in the range of 10 nm to 5 μm, preferably in the range of 50 to 200 nm.

  In order to transmit emitted light, it is convenient if either the anode or the cathode of the organic EL element is transparent or translucent to increase the emission luminance.

  Also, after preparing the metal in the thickness of 1 to 20 nm on the cathode, by producing the conductive transparent material mentioned in the description of the anode thereon, it is possible to produce a transparent or translucent cathode, By applying this, an element in which both the anode and the cathode have light transmittance can be manufactured.

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

  Examples of the resin film include polyester such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyethylene, polypropylene, cellophane, cellulose diacetate, cellulose triacetate (TAC), cellulose acetate butyrate, and cellulose acetate propionate ( CAP), cellulose esters such as cellulose acetate phthalate and cellulose nitrate or derivatives thereof, polyvinylidene chloride, polyvinyl alcohol, polyethylene vinyl alcohol, syndiotactic polystyrene, polycarbonate, norbornene resin, polymethylpentene, polyetherketone, polyimide , Polyether sulfone (PES), polyphenylene sulfide, polysulfones, Cycloethers such as reetherimide, polyetherketoneimide, polyamide, fluororesin, nylon, polymethylmethacrylate, acrylic, or polyarylate, ARTON (trade name, manufactured by JSR) or Apel (trade name, manufactured by Mitsui Chemicals) Base resin and the like.

An inorganic or organic coating or a hybrid coating 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. And a relative humidity (90 ± 2)% RH) of 0.01 g / (m ² · 24 h) or less. Further, the film is measured by a method in accordance with JIS K 7126: 1987. oxygen ^{permeability, 1 × 10 -3 mL / (} m 2 · 24h · atm) or less, the water vapor permeability ^{is, 1 × 10 -5 g / (} m 2 · 24h) that following a high gas barrier film Is preferred.

  As a material for forming the gas barrier film, any material that causes deterioration of the element such as moisture or oxygen and has a function of suppressing intrusion may be used, and examples thereof include silicon oxide, silicon dioxide, and silicon nitride. Further, in order to improve the brittleness of the film, it is more preferable to have a laminated structure of these inorganic layers and a layer made of an organic material. The order of laminating the inorganic layer and the organic layer is not particularly limited, but it is preferable that both are alternately laminated plural times.

  There is no particular limitation on the method of forming the gas barrier film, and examples thereof include a vacuum deposition method, a sputtering method, a reactive sputtering method, a molecular beam epitaxy method, a cluster ion beam method, an ion plating method, a plasma polymerization method, and an atmospheric pressure plasma weight method. Although a legal method, a plasma CVD method, a laser CVD method, a thermal CVD method, a coating method, and the like can be used, an atmospheric pressure plasma polymerization method described in JP-A-2004-68143 is particularly preferable.

  Examples of the opaque support substrate include a metal plate such as aluminum and stainless steel, a film, an opaque resin substrate, and a ceramic substrate.

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

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

  Further, a hue improving filter such as a color filter or the like may be used in combination, or a color conversion filter for converting the emission color of 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. The sealing member may be disposed so as to cover the display area of the organic EL element, and may have a concave plate shape or a flat plate shape. In addition, 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 or a metal film can be preferably used because the organic EL element can be thinned. Furthermore, the polymer film JIS K 7126: oxygen permeability measured in compliance with the method 1987 is ^{1 × 10 -3 mL / (m} 2 · 24h · atm) or less, JIS K 7129: a method conforming to 1992 the measured water vapor transmission rate (25 ± 0.5 ° C., relative humidity (90 ± 2)%) is preferably that of ^{1 × 10 -3 g / (m} 2 · 24h) or less.

  To process the sealing member into a concave shape, sand blasting, chemical etching, or the like is used.

  Specific examples of the adhesive include an acrylic acid-based oligomer, a photocurable and thermosetting adhesive having a reactive vinyl group of a methacrylic acid-based oligomer, and a moisture-curable adhesive such as 2-cyanoacrylate. be able to. In addition, a heat and chemical curing type (two-liquid mixture) of an epoxy type or the like can be used. In addition, hot melt type polyamide, polyester, and polyolefin can be used. In addition, a cation-curable ultraviolet-curable epoxy resin adhesive can be used.

  In addition, since the organic EL element may be deteriorated by the heat treatment, it is preferable that the organic EL element can be adhesively cured from room temperature (25 ° C.) to 80 ° C. Further, a desiccant may be dispersed in the adhesive. A commercially available dispenser may be used for applying the adhesive to the sealing portion, or printing may be performed like screen printing.

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

  Further, in order to improve the brittleness of the film, it is preferable to have a laminated structure of these inorganic layers and a layer made of an organic material. The method for forming these films is not particularly limited, and examples thereof include a vacuum deposition method, a sputtering method, a reactive sputtering method, a molecular beam epitaxy method, a cluster ion beam method, an ion plating method, a plasma polymerization method, and an atmospheric pressure plasma pressure method. A legal 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 a fluorinated hydrocarbon or silicon oil may be injected in a gas phase or a liquid phase. preferable. It is also possible to make a vacuum. Further, a hygroscopic compound can be sealed inside.

  Examples of the hygroscopic compound include metal oxides (eg, sodium oxide, potassium oxide, calcium oxide, barium oxide, magnesium oxide, aluminum oxide, etc.) and sulfates (eg, 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, etc.), and sulfates, metal halides and perchloric acids are preferably anhydrous salts.

《Protective film, protective plate》
A protective film or a protective plate may be provided outside the sealing film or the sealing film on the side facing the support substrate with the organic functional layer interposed therebetween in order to increase the mechanical strength of the element. In particular, when sealing is performed by a sealing film, the mechanical strength is not always 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, a glass plate, a polymer plate / film, a metal plate / film, etc. similar to those used for the above-mentioned sealing can be used. It is preferable to use

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

  As a method for improving the light extraction efficiency, for example, a method of forming irregularities on the surface of a transparent substrate to prevent total reflection at the interface between the transparent substrate and air (for example, US Pat. No. 4,774,435), A method of improving efficiency by imparting light condensing property (for example, JP-A-63-31479), a method of forming a reflection surface on a side surface of an element or the like (for example, JP-A-1-220394), A flat layer having an intermediate refractive index between the substrate and the luminous body to form an anti-reflection film (for example, JP-A-62-172691). (For example, Japanese Unexamined Patent Application Publication No. 2001-202827), and a method of forming a diffraction grating between any one of the substrate, the transparent electrode layer, and the light-emitting layer (including between the substrate and the outside world). (Japanese Unexamined Patent Publication No. JP), etc. -283751 and the like.

  In the present invention, these methods can be used in combination with the organic EL element 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-emitting body, or a method of introducing the substrate into a transparent layer A method of forming a diffraction grating between any of the electrode layers and the light emitting layer (including between the substrate and the outside world) can be suitably used.

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

  When a medium with a low refractive index is formed between the transparent electrode and the transparent substrate with a thickness longer than the wavelength of light, the light emitted 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. Further, it is more preferable to be 1.35 or less.

  Further, the thickness of the low refractive index medium is desirably 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 thickness of the electromagnetic wave oozed by evanescent enters the substrate.

  The method of introducing a diffraction grating into an interface that causes total reflection or any of the media is characterized by a high effect of improving light extraction efficiency. 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, and it is generated from the light-emitting layer. Of the light, the light that cannot escape outside due to total reflection between layers, etc., is diffracted by introducing a diffraction grating into any layer or medium (in a transparent substrate or a transparent electrode), It tries to take light out.

The diffraction grating to be introduced preferably has a two-dimensional periodic refractive index. This is because light emitted from the light-emitting layer is randomly generated in all directions, so that a general one-dimensional diffraction grating having a periodic refractive index distribution only in a certain direction diffracts only light traveling in a specific direction. However, 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 increases.

  The position where the diffraction grating is introduced may be between any layers or in a medium (in a transparent substrate or a transparent electrode), but is preferably near 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.

《Light collecting sheet》
The organic EL element of the present invention is processed, for example, so as to provide a structure on a microlens array on the light extraction side of a support substrate (substrate), or is combined with a so-called light-collecting sheet to form a specific direction, for example, By condensing light 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 the microlens array, quadrangular pyramids having a side of 30 μm and an apex angle of 90 degrees are two-dimensionally arranged on the light extraction side of the substrate. One side is preferably in the range of 10 to 100 μm. If it is smaller than this, the effect of diffraction occurs and coloring occurs, and if it is too large, the thickness becomes undesirably thick.

  As the condensing sheet, for example, a sheet practically used in an LED backlight of a liquid crystal display device can be used. 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, a △ -shaped stripe having a vertex angle of 90 degrees and a pitch of 50 μm may be formed on the substrate, or a shape in which the vertex angle is rounded, and the pitch is randomly changed. The shape may be a bent shape or another shape.

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

《Applications》
The organic EL element of the present invention can be used as a display device, a display, and various light emission light sources.

  Examples of light emitting light sources include lighting devices (home lighting, car interior lighting), clocks and backlights for LCDs, signboard advertisements, traffic lights, light sources for optical storage media, light sources for electrophotographic copiers, light sources for optical communication processors, and light sources. Examples include, but are not limited to, a light source for a sensor, but the present invention can be effectively used particularly as a backlight for 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 inkjet printing method, or the like at the time of film formation, if necessary. When patterning, only the electrode may be patterned, the electrode and the light emitting layer may be patterned, or all the layers of the element may be patterned. In the production of the element, a conventionally known method is used. Can be.

《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 a configuration of a display device including an organic EL element according to the present invention. The display device displays image information by emitting light from the organic EL element. 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 section B is electrically connected to the display section A. The control unit B sends a scanning signal and an image data signal to each of the plurality of pixels based on external image information. 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 section A has a wiring section including a plurality of scanning lines 5 and data lines 6 and a plurality of pixels 3 on a substrate.

  The main members 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 white arrow direction (downward). The scanning lines 5 and the plurality of data lines 6 of the wiring portion are each 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 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 in accordance with the received image data.

  By arranging pixels in a red region, pixels in a green region, and pixels in a blue region with appropriate colors in parallel on the same substrate, a full-color display is possible.

《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, and a 300 μm-thick glass substrate is used as a sealing substrate, and an epoxy-based photocurable adhesive (Lux made by Toagosei Co., Ltd.) Track LC0629B) is applied, superimposed on the cathode, brought into close contact with the transparent support substrate, irradiated with UV light from the glass substrate side, cured, sealed, and illuminated as shown in FIGS. Can be formed.

  FIG. 3 is a schematic view of a lighting device, in which the organic EL element 101 of the present invention is covered with a glass cover 102 (the sealing operation with the glass cover involves bringing the organic EL element 101 into contact with the atmosphere. In a glove box under a nitrogen atmosphere (in an atmosphere of a high-purity nitrogen gas having a purity of 99.999% or more).)

  FIG. 4 is 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 a nitrogen gas 108 and a water catching agent 109 is provided.

  Hereinafter, the present invention will be described specifically with reference to examples, but the present invention is not limited thereto.

[Example 1]
With respect to 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 a solution state and a film state were evaluated.

《Measurement of absolute quantum yield in solution state》
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 device C9920-02 (manufactured by Hamamatsu Photonics).

《Absolute quantum yield measurement in film state》
A quartz substrate having a size of 30 mm × 30 mm and a thickness of 0.7 mm was subjected to ultrasonic cleaning 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 evaporation apparatus.
Each of the fluorescent compounds shown in Tables I-1 and I-2 was filled in a crucible for vapor deposition in the vacuum vapor deposition apparatus in an optimum amount for a single film of the fluorescent compound. The crucible for vapor deposition used was made of a molybdenum or tungsten resistance heating material.
After the pressure was reduced to a degree of vacuum of 1 × 10 ⁻⁴ Pa, each fluorescent compound was deposited at a deposition rate of 0.1 nm / sec to form a single film having a thickness of 30 nm.
The absolute quantum yield (PLQE) of each of the prepared fluorescent compound single films was measured. The absolute quantum yield was measured using an absolute quantum yield measuring device C9920-02 (manufactured by Hamamatsu Photonics).

"Evaluation results"
For each fluorescent compound, the value of the ratio of the measured absolute quantum yield in the 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.

◎: Absolute quantum yield in film state / absolute quantum yield in 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)
×: Absolute quantum yield in film state / absolute quantum yield in solution state is less than 0.5 (poor, failed)

As is clear from Tables I-1 and I-2, the fluorescent compound of the present invention shows a smaller decrease in the absolute quantum yield in the film state as compared with 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 considered to be because the fluorescent compound of the present invention has a substituent Y, so that spontaneous aggregation of molecules and the like hardly occur, and as a result, concentration quenching did not occur even in a solid state. Can be
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 a solid state.

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

<Production of lighting device 201 for evaluation>
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 subjected to a cleaning treatment. 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 is formed on the ITO film. A film was formed.
Next, N, N'-di-[(1-naphthyl) -N, N'-diphenyl] -1,1 "-biphenyl) -4,4'-diamine is formed as a hole transport material. (25 nm).
Next, as a light emitting material (fluorescent compound), a film in which 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 ) is deposited as an electron transporting material (30 nm), and then lithium fluoride (LiF) (1.0 nm) is used as an electron injecting material and aluminum is used 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 having 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 photocurable adhesive (Lux Track LC0629B manufactured by Toagosei Co., Ltd.) is applied as a sealant around the periphery, and this is superimposed on the cathode, brought into 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 lighting device 201 having a configuration as shown in FIGS.

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

《Evaluation》
Luminous efficiency and half-life were evaluated for the manufactured evaluation lighting devices 201 to 270.
The evaluation results are shown in Tables II-1 and II-2.

<Measurement of luminous efficiency>
Each of the manufactured lighting devices for evaluation was lit at room temperature (25 ° C.) under a constant current density condition of ^2.5 mA / cm ² , and emitted light using a spectroradiometer CS-2000 (manufactured by Konica Minolta). The luminance was measured, and the luminous efficiency (external quantum efficiency) at the current value was determined.
In Tables II-1 and II-2, the luminous efficiencies are indicated by relative values. For example, the luminous efficiencies of the lighting devices 201, 202, and 204 to 219 are assumed to be 1.0 for the luminous efficiency of the lighting device 203. It is a relative value of time.

<Measurement of half life>
The luminance of each of the manufactured lighting devices for evaluation was measured using a spectral radiance meter CS-2000, and the time (LT50) at which the measured luminance was reduced by half was determined as the 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-life of the lighting devices 201, 202, and 204 to 219 is 1.0 with the half-life of the lighting device 203 set to 1.0. It is a relative value of time.

  As is clear from Tables II-1 and II-2, the lighting device containing the fluorescent compound of the present invention has higher luminous efficiency and a half reduction than the lighting device containing the comparative compound of the comparative example. It can be seen that the life is extended. This is because the fluorescent compound of the present invention has a substituent Y, so that spontaneous aggregation or the like of molecules is unlikely to 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 lighting device for evaluation >>
The lighting devices for evaluation 301 to 318 were manufactured as follows.

<Preparation of lighting device 301 for evaluation>
(Formation of anode)
On a 50 mm × 50 mm, 0.7 mm thick glass substrate (transparent substrate), a 150 nm thick ITO (indium tin oxide) film was formed as an anode, and after patterning, this ITO transparent electrode was The attached transparent substrate was subjected to ultrasonic cleaning with isopropyl alcohol, dried with dry nitrogen gas, and subjected to UV ozone cleaning for 5 minutes.
In each of the resistance heating boats for vapor deposition in the vacuum vapor deposition apparatus, the constituent material of each layer was filled in an amount optimal for producing each element. The resistance heating boat was made of molybdenum or tungsten.

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

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

(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, so that the host compound H-1, the phosphorescent compound Dp-1 and the fluorescent light are emitted. The deposition rates were 0.56 ° / sec, 0.1 ° / sec, and 0.006 ° / sec, respectively, so that the comparative compound 4 as the neutral compound was 84.5% by volume, 15% by volume, and 0.5% by volume, respectively. Was 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 as an electron transport layer on the light emitting layer. Specifically, HB-1 was deposited at a deposition rate of 1.0 ° / sec to form a 30 nm-thick first electron transport layer. Further, ET-1 was deposited thereon at a deposition rate of 1.0 ° / sec to form a second electron transport layer having a thickness of 30 nm.

(Formation of cathode)
After that, lithium fluoride was evaporated to a thickness of 0.5 nm, and aluminum was evaporated to a thickness of 100 nm to form a cathode, thereby producing an organic EL device 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 having 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 photocurable adhesive (Lux Track LC0629B manufactured by Toagosei Co., Ltd.) is applied as a sealant around the periphery, and this is superimposed on the cathode, brought into 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 lighting device 301 having a configuration as shown in FIGS.

<Production of lighting devices 302 to 318 for evaluation>
The lighting devices for evaluation 302 to 318 were manufactured in the same manner as in the manufacturing of the lighting device for evaluation 301 except that the fluorescent compound was changed as shown in Table III.

《Evaluation》
The luminous efficiency of the produced evaluation lighting devices 301 to 318 was evaluated.
Table III shows the evaluation results.

<Measurement of luminous efficiency>
Each of the manufactured lighting devices for evaluation was lit at room temperature (25 ° C.) under a constant current density condition of ^2.5 mA / cm ² , and emitted light using a spectroradiometer CS-2000 (manufactured by Konica Minolta). The luminance was measured, and the luminous efficiency (external 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, 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 a substituent Y, so that spontaneous aggregation or the like of molecules is unlikely to 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 lighting device for evaluation >>
Illumination devices 401 to 420 for evaluation were prepared 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 manufactured evaluation lighting devices 401 to 420 was evaluated.
The evaluation results are shown in Table IV.

<Measurement of luminous efficiency>
Each of the manufactured lighting devices for evaluation was lit at room temperature (25 ° C.) under a constant current density condition of ^2.5 mA / cm ² , and emitted light using a spectroradiometer CS-2000 (manufactured by Konica Minolta). The luminance was measured, and the luminous efficiency (external 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 clear 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 a substituent Y, so that spontaneous aggregation or the like of molecules is unlikely to 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 lighting device for evaluation >>
The lighting devices for evaluation 501 to 519 were manufactured as follows.

<< Preparation of evaluation lighting device 501 >>
As a positive electrode, after patterning a substrate (NA45 manufactured by NH Techno Glass Co., Ltd.) on which 100 nm of ITO (indium tin oxide) was formed on a glass substrate of 100 mm × 100 mm × 1.1 mm, this ITO transparent electrode was provided. The transparent support substrate thus obtained was subjected to ultrasonic cleaning with isopropyl alcohol, dried with dry nitrogen gas, and subjected to UV ozone cleaning for 5 minutes.
On this transparent support substrate, 3000 rpm using a solution obtained by diluting poly (3,4-ethylenedioxythiophene) -polystyrene sulfonate (PEDOT / PSS, Baytron, Baytron P Al 4083) to 70% by mass with pure water. 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.

  The 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 optimal amount for producing each element. The crucible for vapor deposition used was made of a molybdenum or tungsten resistance heating material.

After the pressure was reduced to a degree of vacuum of 1 × 10 ⁻⁴ Pa, α-NPD was deposited on the hole injection layer at a deposition rate of 0.1 nm / sec to form a hole transport layer having a thickness of 40 nm.

  Next, H-2 was used as the host compound, Dp-3 was used as the thermally activated delayed fluorescent compound, and Comparative Compound 8 was used as the fluorescent compound. The ratios were 84.5% by volume, 15% by volume, and 0.5% by volume, respectively. %, And was co-deposited at a deposition rate of 0.1 nm / sec 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 / sec to form an electron transporting layer having a thickness of 30 nm.

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

  The non-light-emitting surface side of the element was covered with a can-shaped glass case in an atmosphere of high-purity nitrogen gas having a purity of 99.999% or more, and wiring for taking out electrodes was provided.

<Production of lighting devices 502 to 519 for evaluation>
Lighting devices for evaluation 502 to 519 were prepared in the same manner as in the manufacture of the lighting device for evaluation 501, except that the fluorescent compound was changed as shown in Table V.

《Evaluation》
The luminous efficiency of the manufactured evaluation lighting devices 501 to 519 was evaluated.
Table V shows the evaluation results.

<Measurement of luminous efficiency>
Each of the manufactured lighting devices for evaluation was lit at room temperature (25 ° C.) under a constant current density condition of ^2.5 mA / cm ² , and emitted light using a spectroradiometer CS-2000 (manufactured by Konica Minolta). The luminance was measured, and the luminous efficiency (external 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 evident from Table V, 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 a substituent Y, so that spontaneous aggregation or the like of molecules is unlikely to 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 preferably used to provide a fluorescent compound, an organic material composition, a luminescent film, an organic electroluminescent device material, and an organic electroluminescent device that suppress concentration quenching in a solid state. .

Reference Signs List 1 display 3 pixel 5 scanning 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 catching agent A Display unit B Control unit

Claims (20)

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 of 14π electron system or more. Y represents a deuterium atom, a halogen atom, a cyano group, a nitro group, a hydroxy group, a mercapto group, an alkyl group, a 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, heteroarylsulfonyl group, amino group, fluorinated hydrocarbon group, triarylsilyl group, diarylalkylsilyl group, aryldialkylsilyl group, Trialkylsilyl group, Represents a phosphate group, a phosphite group, a phosphono group, a phenyl group, or a group having a structure represented by the following general formula (2), and these may further have a substituent. At least one is a group having a structure represented by the following general formula (2): when there are a plurality of Y, they may be the same or different from each other; Represents the number of Y that can be substituted for a hydrogen atom on the ring, and represents an integer from 1 to the maximum number.)

(In the general formula (2), R ^{1 to} R ⁵ each independently represent 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, 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 to X.)

(In the general formula (3), A represents a carbon atom or a silicon atom. R ^{6 to} R ⁸ each independently represent the same atom or substituent as R ^{1 to} R ⁵ in the 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 the general formula (4), R ⁹ and R ¹⁰ each independently represent the same atom or substituent as R ^{1 to} R ⁵ in the general formula (2), and at least one has 1 or more carbon atoms. * 3 represents a bonding site to an adjacent atom, and R ^{1 to} R ¹⁰ in the general formulas (2) to (4) represent a substituted or unsubstituted aliphatic group in which adjacent groups are bonded to each other. A ring may be formed, but the formed aliphatic ring is not further condensed with an aromatic 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 of 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: at least one of Y is represented by the following general formula (2a) When there are a plurality of Y's, they may be the same or different, and n is the number of Y's which 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), and 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 are bonded to each other to form a substituted or unsubstituted aliphatic ring. The aromatic ring formed at this time does not further condense with the aromatic ring.) 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 fluorescent compound according to claim 1.

(In the general formulas (5) to (19), R represents a hydrogen atom or a bonding site to Y in the general formula (1) or (1a), but not all are hydrogen atoms. R may be the same or different from each other.
In the general formula (20) and (21), L ^{is, -CR 11 R 12 -, -} O -, - NR 13 -, - SiR 14 R 15 - or an -S-. A plurality of L may be the same or different from each other. R and R ^{11 to} R ¹⁵ each independently represent a hydrogen atom or a bonding site to Y in the general formula (1) or (1a), but not all are hydrogen atoms. A plurality of Rs may be the same or different from each other. ) 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 (33) to (52). The fluorescent compound according to claim 1.

(In the general formulas (33) to (49), R represents a bonding site to Y in the general formula (1) or (1a). Rs may be the same or different.
In the general formula (50) ~ (52), L ^{is, -CR 11 R 12 -, -} O -, - NR 13 -, - SiR 14 R 15 - or an -S-. A plurality of L may be the same or different from each other. R represents a bonding site to Y in the general formula (1) or (1a). R ^{11 to} R ¹⁵ each independently represent a hydrogen atom or a bonding site to Y in the general formula (1) or (1a). A plurality of R and R ^{11 to} R ¹⁵ may be the same or different from each other. )   The fluorescent compound according to claim 5, wherein Rs in the general formulas (33) to (52) are all groups having a structure represented by the general formula (2a).   The fluorescence according to claim 5, wherein one of Rs in the general formulas (33) to (52) is a triarylsilyl group, and all the other Rs are groups having a structure represented by the general formula (2a). Luminescent compound. The R ¹ and R ⁵ in the general formula (2) or (2a) are each represented by the general formula (3) or (4), 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 comprising the fluorescent compound according to any one of claims 1 to 8. An organic electroluminescent device 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 of 14π electron system or more. Y represents a deuterium atom, a halogen atom, a cyano group, a nitro group, a hydroxy group, a mercapto group, an alkyl group, a 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, heteroarylsulfonyl group, amino group, fluorinated hydrocarbon group, triarylsilyl group, diarylalkylsilyl group, aryldialkylsilyl group, Trialkylsilyl group, Represents a phosphate group, a phosphite group, a phosphono group, a phenyl group, or a group having a structure represented by the following general formula (2), and these may further have a substituent. At least one is a group having a structure represented by the following general formula (2): when there are a plurality of Y, they may be the same or different from each other; Represents the number of Y that can be substituted for a hydrogen atom on the ring, and represents an integer from 1 to the maximum number.)

(In the general formula (2), R ^{1 to} R ⁵ each independently represent 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, 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 to X.)

(In the general formula (3), A represents a carbon atom or a silicon atom. R ^{6 to} R ⁸ each independently represent the same atom or substituent as R ^{1 to} R ⁵ in the 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 the general formula (4), R ⁹ and R ¹⁰ each independently represent the same atom or substituent as R ^{1 to} R ⁵ in the general formula (2), and at least one has 1 or more carbon atoms. * 3 represents a bonding site to an adjacent atom, and R ^{1 to} R ¹⁰ in the general formulas (2) to (4) represent a substituted or unsubstituted aliphatic group in which adjacent groups are bonded to each other. A ring may be formed, but the formed aliphatic ring is not further condensed with an aromatic ring.) Wherein at least one of R ¹ and R ⁵ in the general formula (2) The organic electroluminescent device material according to claim 12 represented by the general formula (3). 14. The organic electroluminescent device material according to claim 12, 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 of 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: at least one of Y is represented by the following general formula (2a) When there are a plurality of Y's, they may be the same or different, and n is the number of Y's which 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), and 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 are bonded to each other to form a substituted or unsubstituted aliphatic ring. The aromatic ring formed at this time does not further condense with the aromatic ring.) 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). 9. The organic electroluminescent device material according to claim 1.

(In the general formulas (5) to (19), R represents a hydrogen atom or a bonding site to Y in the general formula (1) or (1a), but not all are hydrogen atoms. R may be the same or different from each other.
In the general formula (20) and (21), L ^{is, -CR 11 R 12 -, -} O -, - NR 13 -, - SiR 14 R 15 - or an -S-. A plurality of L may be the same or different from each other. R and R ^{11 to} R ¹⁵ each independently represent a hydrogen atom or a bonding site to Y in the general formula (1) or (1a), but not all are hydrogen atoms. A plurality of Rs may be the same or different from each other. ) 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 (33) to (52). 9. The organic electroluminescent device material according to claim 1.

(In the general formulas (33) to (49), R represents a bonding site to Y in the general formula (1) or (1a). Rs may be the same or different.
In the general formula (50) ~ (52), L ^{is, -CR 11 R 12 -, -} O -, - NR 13 -, - SiR 14 R 15 - or an -S-. A plurality of L may be the same or different from each other. R represents a bonding site to Y in the general formula (1) or (1a). R ^{11 to} R ¹⁵ each independently represent a hydrogen atom or a bonding site to Y in the general formula (1) or (1a). A plurality of R and R ^{11 to} R ¹⁵ may be the same or different from each other. )   17. The organic electroluminescent device material according to claim 16, wherein Rs in the general formulas (33) to (52) are all groups having a structure represented by the general formula (2a).   The organic compound according to claim 16, wherein one of Rs in the general formulas (33) to (52) is a triarylsilyl group, and all other Rs are groups having a structure represented by the general formula (2a). Electroluminescent device material. 19. The method according to claim 12, wherein R ¹ and R ⁵ in the general formula (2) or (2a) are each represented by the general formula (3) or (4), and have different structures. The organic electroluminescence device material according to any one of the above. An organic electroluminescence device having an organic functional layer including at least a light emitting layer between the anode and the cathode,
20. An organic electroluminescent device, wherein the organic functional layer contains the organic electroluminescent device material according to claim 12.

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