CN112341469A

CN112341469A - Organic compound, light-emitting device, light-emitting apparatus, electronic device, and lighting apparatus

Info

Publication number: CN112341469A
Application number: CN202010788941.1A
Authority: CN
Inventors: 原朋香; 吉住英子; 濑尾哲史
Original assignee: Semiconductor Energy Laboratory Co Ltd
Current assignee: Semiconductor Energy Laboratory Co Ltd
Priority date: 2019-08-07
Filing date: 2020-08-07
Publication date: 2021-02-09
Also published as: JP2021024863A; KR20210018142A

Abstract

Provided is a benzofuran-pyridazine derivative of a novel organic compound. The organic compound is represented by the following general formula (G1).

In the general formula (G1), Q represents oxygen or sulfur. A is a group having 12 to 100 carbon atoms in total, and has a structure containing a benzene ring, a naphthalene ring, a fluorene ring, a phenanthrene ring, and a triphenylene ringOne or more of a heteroaromatic ring of a dibenzothiophene ring, a heteroaromatic ring comprising a dibenzofuran ring, a heteroaromatic ring comprising a carbazole ring, a benzimidazole ring, and a triphenylamine structure. In addition, R¹To R⁵Each independently represents hydrogen, an alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted monocyclic saturated hydrocarbon having 5 to 7 carbon atoms, a substituted or unsubstituted polycyclic saturated hydrocarbon having 7 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 13 carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 to 12 carbon atoms.

Description

Organic compound, light-emitting device, light-emitting apparatus, electronic device, and lighting apparatus

Technical Field

One embodiment of the present invention relates to an organic compound, a light-emitting device, an electronic apparatus, and a lighting device. Note that one embodiment of the present invention is not limited to the above-described technical field. That is, one embodiment of the present invention relates to an object, a method, a manufacturing method, or a driving method. Alternatively, one embodiment of the present invention relates to a process (process), machine (machine), product (manufacture), or composition (machine). Specifically, a semiconductor device, a display device, a liquid crystal display device, and the like can be given as examples.

Background

Since a light-emitting device (also referred to as an organic EL element) including an EL layer between a pair of electrodes has characteristics such as a thin and lightweight structure, high-speed response to an input signal, and low power consumption, a display using the light-emitting device has been rapidly developed and receives great attention.

In the light-emitting device, when a voltage is applied between a pair of electrodes, electrons and holes injected from the respective electrodes are recombined in the EL layer, and a light-emitting substance (organic compound) included in the EL layer is brought into an excited state, and light is emitted when the excited state returns to a ground state. Further, as the kind of excited state, a singlet excited state (S) may be mentioned^*) And triplet excited state (T)^*) In this case, light emission from a singlet excited state is referred to as fluorescence, and light emission from a triplet excited state is referred to as phosphorescence. In addition, in the light-emitting device, the statistical generation ratio of the singlet excited state and the triplet excited state is considered to be S^*：T^*1: 3. an emission spectrum obtained from a luminescent material is peculiar to the luminescent material, and by using different kinds of organic compounds as the luminescent material, a light emitting device emitting various luminescent colors can be obtained.

In such a light-emitting device, improvement of an element structure, development of a material, and the like are actively performed in order to improve element characteristics (for example, see patent document 1).

[ patent document 1] Japanese patent application laid-open No. 2010-182699

Disclosure of Invention

Accordingly, one embodiment of the present invention provides a novel organic compound. In addition, one embodiment of the present invention provides a novel organic compound having a benzofuro [3,2-c ] pyridazine skeleton or a benzothieno [3,2-c ] pyridazine skeleton. In addition, one embodiment of the present invention provides a novel organic compound which can be used for a light-emitting device. In addition, one embodiment of the present invention provides a novel organic compound which can be used for an EL layer of a light-emitting device. In addition, one embodiment of the present invention provides a novel light-emitting device with high reliability using the novel organic compound of one embodiment of the present invention. In addition, one embodiment of the present invention provides a novel light-emitting device, a novel electronic device, or a novel lighting device. Note that the description of these objects does not hinder the existence of other objects. Note that one mode of the present invention is not required to achieve all the above-described objects. Note that, the objects other than the above-described object are obvious from the description of the specification, the drawings, the claims, and the like, and the objects other than the above-described object can be obtained from the description of the specification, the drawings, the claims, and the like.

One embodiment of the present invention is a benzofuropyridazine derivative, which is an organic compound represented by the following general formula (G1). Further, the organic compound represented by the following general formula (G1) has a benzofuro [3,2-c ] pyridazine skeleton or a benzothieno [3,2-c ] pyridazine skeleton.

[ chemical formula 1]

In the above general formula (G1), Q represents oxygen or sulfur. In addition, a is a group having 12 to 100 total carbon atoms, and has one or more of a benzene ring, a naphthalene ring, a fluorene ring, a phenanthrene ring, a triphenylene ring, a heteroaromatic ring of a dibenzothiophene ring, a heteroaromatic ring of a dibenzofuran ring, a heteroaromatic ring of a carbazole ring, a benzimidazole ring, and a triphenylamine structure. In addition, R¹To R⁵Each independently represents hydrogen, an alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted monocyclic saturated hydrocarbon having 5 to 7 carbon atoms, a substituted or unsubstituted polycyclic saturated hydrocarbon having 7 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 13 carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 to 12 carbon atoms.

In another embodiment of the present invention, the benzothienopyridazine derivative is an organic compound represented by the following general formula (G2). Further, as shown by the following general formula (G2), the compound has a hole-transporting skeleton in three positions of a benzofuro [3,2-c ] pyridazine skeleton or a benzothieno [3,2-c ] pyridazine skeleton.

[ chemical formula 2]

In the above general formula (G2), Q represents oxygen or sulfur. In addition, α represents a substituted or unsubstituted phenylene group, and n represents an integer of 0 to 4. In addition, Ht_uniRepresents a skeleton having a hole-transporting property. In addition, R¹To R⁵Represents hydrogen, an alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted monocyclic saturated hydrocarbon having 5 to 7 carbon atoms, a substituted or unsubstituted polycyclic saturated hydrocarbon having 7 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 13 carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 to 12 carbon atoms.

In another embodiment of the present invention, the benzofuropyridazine derivative is an organic compound represented by the following general formula (G3). Further, as shown by the following general formula (G3), the compound has a hole-transporting skeleton in three positions of a benzofuro [3,2-c ] pyridazine skeleton or a benzothieno [3,2-c ] pyridazine skeleton.

[ chemical formula 3]

In the above general formula (G3), Q represents oxygen or sulfur.In addition, Ht_uniRepresents a skeleton having a hole-transporting property. In addition, R¹To R⁵Represents hydrogen, an alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted monocyclic saturated hydrocarbon having 5 to 7 carbon atoms, a substituted or unsubstituted polycyclic saturated hydrocarbon having 7 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 13 carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 to 12 carbon atoms.

In each of the above structures, Ht in the general formulae (G2) and (G3) is_uniEach independently has any one of a pyrrole ring structure, a furan ring structure and a thiophene ring structure.

In each of the above structures, Ht in the general formulae (G2) and (G3) is_uniEach independently represented by any one of the following general formulae (Ht-1) to (Ht-26).

[ chemical formula 4]

[ chemical formula 5]

In the above general formulae (Ht-1) to (Ht-26), Q represents oxygen or sulfur. In addition, R²To R⁷¹Each represents a substituent of 1 to 4, and each independently represents any of hydrogen, an alkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted phenyl group. In addition, Ar¹Represents a substituted or unsubstituted aryl group having 6 to 13 carbon atoms.

Another embodiment of the present invention is an organic compound represented by any one of structural formulae (100) and (101).

[ chemical formula 6]

Another embodiment of the present invention is a light-emitting device using the organic compound according to the above-described embodiment of the present invention. Further, a light-emitting device containing not only the above-described organic compound but also a guest material is also included in the scope of the present invention.

Another embodiment of the present invention is a light-emitting device using the organic compound according to the above-described embodiment of the present invention. In addition, a light-emitting device in which an EL layer between a pair of electrodes and a light-emitting layer in the EL layer are formed using an organic compound which is one embodiment of the present invention is also included in the scope of the present invention. In addition, the present invention includes a light-emitting device including, in addition to the above-described light-emitting device, a layer which is in contact with an electrode and includes an organic compound (e.g., a cap layer). Further, a light-emitting device including a transistor, a substrate, or the like is included in the scope of the invention in addition to the light-emitting device. Further, an electronic device and a lighting device including a microphone, a camera, an operation button, an external connection portion, a housing, a cover, a support base, a speaker, and the like, in addition to the light-emitting device are also included in the scope of the invention.

One embodiment of the present invention includes not only a light-emitting device including a light-emitting device but also a lighting device including a light-emitting device. Therefore, the light-emitting device in this specification refers to an image display device or a light source (including a lighting device). In addition, the light-emitting device further includes the following modules: a module that connects a connector such as an FPC (Flexible printed circuit) or a TCP (Tape Carrier Package) to the light emitting device; a module for arranging the printed circuit board at the end of the TCP; or a module in which an IC (integrated circuit) is directly mounted On a light emitting device by a COG (Chip On Glass) method.

One embodiment of the present invention can provide a novel organic compound. In addition, one embodiment of the present invention can provide a novel organic compound having a benzofuro [3,2-c ] pyridazine skeleton or a benzothieno [3,2-c ] pyridazine skeleton. In addition, one embodiment of the present invention can provide a novel organic compound which can be used for a light-emitting device. In addition, one embodiment of the present invention can provide a novel organic compound which can be used for an EL layer of a light-emitting device. In addition, by using the novel organic compound according to one embodiment of the present invention, a novel light-emitting device with high reliability can be provided. In addition, a novel light-emitting device, a novel electronic apparatus, or a novel lighting device can be provided.

Drawings

Fig. 1A, 1B, 1C, 1D, and 1E are diagrams illustrating the structure of a light emitting device;

fig. 2A is a diagram illustrating a light-emitting device, fig. 2B is a diagram illustrating a light-emitting device, and fig. 2C is a diagram illustrating a light-emitting device;

fig. 3A is a plan view illustrating a light emitting device, and fig. 3B is a sectional view illustrating the light emitting device;

fig. 4A is a diagram illustrating a mobile computer, fig. 4B is a diagram illustrating a portable image reproduction apparatus, fig. 4C is a diagram illustrating a digital camera, fig. 4D is a diagram illustrating a portable information terminal, fig. 4E is a diagram illustrating a portable information terminal, fig. 4F is a diagram illustrating a television apparatus, and fig. 4G is a diagram illustrating a portable information terminal;

fig. 5A is a diagram illustrating an electronic apparatus, fig. 5B is a diagram illustrating an electronic apparatus, and fig. 5C is a diagram illustrating an electronic apparatus;

fig. 6A is a diagram illustrating an automobile, and fig. 6B is a diagram illustrating an automobile;

fig. 7A is a diagram illustrating an illumination device, and fig. 7B is a diagram illustrating an illumination device;

FIG. 8 shows a schematic view of an organic compound represented by the structural formula (100)¹H-NMR spectrum;

FIG. 9 is an ultraviolet-visible absorption spectrum and an emission spectrum of the organic compound represented by the structural formula (100);

FIG. 10 is a phosphorescence spectrum of the organic compound represented by structural formula (100);

FIG. 11 shows a schematic view of an organic compound represented by the structural formula (101)¹H-NMR spectrum;

fig. 12 shows an ultraviolet-visible absorption spectrum and an emission spectrum of the organic compound represented by structural formula (101).

Detailed Description

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. Note that the present invention is not limited to the following description, and the mode and the details thereof may be changed into various forms without departing from the spirit and the scope of the present invention. Therefore, the present invention should not be construed as being limited to the description of the embodiments shown below.

For convenience of understanding, the positions, sizes, ranges, and the like of the respective components shown in the drawings and the like do not indicate actual positions, sizes, ranges, and the like. Accordingly, the disclosed invention is not necessarily limited to the positions, sizes, ranges, etc., disclosed in the drawings and the like.

Note that in this specification and the like, when the structure of the invention is described with reference to the drawings, symbols indicating the same parts may be used in common in different drawings.

Embodiment mode 1

In this embodiment, an organic compound according to one embodiment of the present invention is described. An organic compound according to one embodiment of the present invention is an organic compound having a benzofuro [3,2-c ] pyridazine skeleton or benzothieno [3,2-c ] pyridazine skeleton represented by the following general formula (G1).

[ chemical formula 7]

Another embodiment of the present invention is an organic compound represented by the following general formula (G2). Further, the organic compound according to one embodiment of the present invention has a hole-transporting skeleton in three positions of a benzofuro [3,2-c ] pyridazine skeleton or benzothieno [3,2-c ] pyridazine skeleton, as shown in the following general formula (G2).

[ chemical formula 8]

Another embodiment of the present invention is an organic compound represented by the following general formula (G3). Further, the organic compound according to one embodiment of the present invention has a hole-transporting skeleton in three positions of a benzofuro [3,2-c ] pyridazine skeleton or benzothieno [3,2-c ] pyridazine skeleton, as shown in the following general formula (G3).

[ chemical formula 9]

In the above general formula (G3), Q represents oxygen or sulfur. In addition, Ht_uniRepresents a skeleton having a hole-transporting property. In addition, R¹To R⁵Represents hydrogen, an alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted monocyclic saturated hydrocarbon having 5 to 7 carbon atoms, a substituted or unsubstituted polycyclic saturated hydrocarbon having 7 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 13 carbon atoms, or a substituted or unsubstituted carbon atomHeteroaryl groups having a sub-number of 3 to 12.

Furthermore, Ht in the above general formulae (G2) and (G3)_uniEach independently has any one of a pyrrole ring structure, a furan ring structure and a thiophene ring structure.

Furthermore, Ht in the above general formulae (G2) and (G3)_uniEach independently represented by any one of the following general formulae (Ht-1) to (Ht-26).

[ chemical formula 10]

[ chemical formula 11]

Further, in the case where the substituted or unsubstituted monocyclic saturated hydrocarbon having 5 to 7 carbon atoms, the substituted or unsubstituted polycyclic saturated hydrocarbon having 7 to 10 carbon atoms, the substituted or unsubstituted aryl group having 6 to 13 carbon atoms or the substituted or unsubstituted heteroaryl group having 3 to 12 carbon atoms in the above general formulae (G1), (G2) and (G3) has a substituent, examples of the substituent include an alkyl group having 1 to 7 carbon atoms such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a pentyl group and a hexyl group, a cycloalkyl group having 5 to 7 carbon atoms such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group and an 8,9, 10-trinorborneyl group, an aryl group having 6 to 12 carbon atoms such as a phenyl group, a naphthyl group and a biphenyl group, and a heteroaryl group having 6 to 13 carbon atoms such as a dibenzothienyl group, a dibenzofuranyl group and a carbazolyl group.

As in the above general formulae (G1), (G2) and (G3)R of (A) to (B)¹To R⁵Specific examples of the monocyclic saturated hydrocarbon having 5 to 7 carbon atoms include cyclopentyl, cyclohexyl, 1-methylcyclohexyl, cycloheptyl, and the like.

R in the above general formulae (G1), (G2) and (G3)¹To R⁵Specific examples of the polycyclic saturated hydrocarbon having 7 to 10 carbon atoms include norbornyl, adamantyl, decahydronaphthyl, tricyclodecanyl and the like.

R in the general formulae (G1), (G2) and (G3)¹To R⁵Specific examples of the aryl group having 6 to 13 carbon atoms include phenyl, o-tolyl, m-tolyl, p-tolyl, mesityl, o-biphenyl, m-biphenyl, p-biphenylyl, 1-naphthyl, 2-naphthyl, and fluorenyl groups.

R in the general formulae (G1), (G2) and (G3)¹To R⁵Specific examples of the alkyl group having 1 to 6 carbon atoms include methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, isobutyl, tert-butyl, pentyl, isopentyl, sec-pentyl, tert-pentyl, neopentyl, hexyl, isohexyl, 3-methylpentyl, 2-ethylbutyl, 1, 2-dimethylbutyl, and 2, 3-dimethylbutyl.

R in the general formulae (G1), (G2) and (G3)¹To R⁵Specific examples of the heteroaryl group having 3 to 12 carbon atoms include triazinyl, pyrazinyl, pyrimidinyl, pyridyl, quinolyl, isoquinolyl, benzothienyl, benzofuranyl, indolyl, dibenzothienyl, dibenzofuranyl, carbazolyl and the like.

Due to R in the above general formulae (G1), (G2), (G3)¹To R⁵Since the organic compound of one embodiment of the present invention has the group shown in the above specific example, it has high thermal stability and physicochemical stability. In particular, at R³Having the group shown in the above specific example, the structure thereof leads to an improvement in thermal stability and has high electron resistance because LUMO is stable, so that light emission is produced by using such a materialThe device can obtain a light-emitting device with high reliability.

Next, a specific structural formula of the organic compound according to one embodiment of the present invention is shown below. Note that the present invention is not limited thereto.

[ chemical formula 12]

[ chemical formula 13]

[ chemical formula 14]

Note that the organic compounds represented by the structural formulae (100) to (121) described above are an example of the organic compound represented by the general formula (G1) described above, but the organic compound of one embodiment of the present invention is not limited thereto.

Method for synthesizing organic Compound represented by general formula (G1)

Next, a method for synthesizing an organic compound having a benzofuro [3,2-c ] pyridazine skeleton or a benzothieno [3,2-c ] pyridazine skeleton represented by the following general formula (G1) will be described.

[ chemical formula 15]

In the above general formula (G1), Q represents oxygen or sulfur. In addition, a is a group having 12 to 100 total carbon atoms, and has one or more of a benzene ring, a naphthalene ring, a fluorene ring, a phenanthrene ring, a triphenylene ring, a heteroaromatic ring of a dibenzothiophene ring, a heteroaromatic ring of a dibenzofuran ring, a heteroaromatic ring of a carbazole ring, a benzimidazole ring, and a triphenylamine structure.In addition, R¹To R⁵Each independently represents hydrogen, an alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted monocyclic saturated hydrocarbon having 5 to 7 carbon atoms, a substituted or unsubstituted polycyclic saturated hydrocarbon having 7 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 13 carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 to 12 carbon atoms.

The following shows a synthesis scheme (a) of the organic compound represented by the above general formula (G1). As shown in the following synthesis scheme (a), the compound represented by the general formula (G1) is obtained by reacting a halogen compound (a1) having a benzofuropyridazine skeleton or benzothienopyridazine skeleton, a boronic acid compound (a2), and a boronic acid compound (A3).

[ chemical formula 16]

In the synthesis scheme (A), Q represents oxygen or sulfur. In addition, a is a group having 12 to 100 total carbon atoms, and has one or more of a benzene ring, a naphthalene ring, a fluorene ring, a phenanthrene ring, a triphenylene ring, a heteroaromatic ring of a dibenzothiophene ring, a heteroaromatic ring of a dibenzofuran ring, a heteroaromatic ring of a carbazole ring, a benzimidazole ring, and a triphenylamine structure. In addition, R¹To R⁵Each independently represents hydrogen, an alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted monocyclic saturated hydrocarbon having 5 to 7 carbon atoms, a substituted or unsubstituted polycyclic saturated hydrocarbon having 7 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 13 carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 to 12 carbon atoms. In addition, X¹、X²Represents halogen, preferably chlorine, bromine or iodine. Y is¹、Y²Represents boric acid, boric acid ester, or cyclic triol borate. Further, as the cyclic triol borate, a potassium salt or a sodium salt may be used in addition to a lithium salt.

In addition, R in the halogen compound (A1) used in the above-mentioned synthesis scheme (A)¹In the case of hydrogen, it can be synthesized as shown in the following synthesis scheme (B)The halogen compound (A1). That is, the intermediate (B4) can be obtained by reacting the halogenated benzofuran-3-one derivative or benzothien-3-one derivative (B1) with glyoxylic acid ester (B2) to obtain intermediate (B3) and then reacting with hydrazine monohydrate. By reacting this intermediate (B4) with a halogenating agent, a halogen compound (a1) having a benzofuropyridazine skeleton or benzothienopyridazine skeleton can be synthesized.

[ chemical formula 17]

In the above synthesis scheme (B), Q represents oxygen or sulfur. In addition, X¹、X²Represents halogen, preferably chlorine, bromine or iodine. In the formula, R⁶Represents an alkyl group, preferably a methyl group or an ethyl group. In addition, glyoxylic acid esters (B2) prepared from a solution or in a polymer form may also be used.

The halogen compound (a1) used in the synthesis scheme (a) can also be synthesized by the method shown in the following synthesis scheme (C). That is, the halogen compound (a1) can also be obtained by cyclizing an intermediate (C3) obtained by reacting a dihalogen compound (C1) with a pyridazine compound (C2) substituted with a hydroxyl group or a mercapto group.

[ Compound 18]

In the synthesis scheme (C), Q represents oxygen or sulfur. In addition, X¹To X⁴Represents halogen, X¹To X³Preferably chlorine, bromine or iodine, X⁴Preferably fluorine or chlorine.

As the compounds (a1), (a2), (A3), (B1), (B2), (B3), (C1), (C2) and (C3) used in the above-mentioned synthesis schemes (a) to (C), various kinds of compounds are commercially available or can be synthesized, so that a wide variety of organic compounds represented by the general formula (G1) can be synthesized. Therefore, the compound according to one embodiment of the present invention has a wide variety of features.

Although the method for synthesizing an organic compound according to one embodiment of the present invention has been described above, the present invention is not limited thereto, and may be synthesized by any other synthesis method.

The structure described in this embodiment can be implemented in appropriate combination with the structures described in the other embodiments.

Embodiment mode 2

In this embodiment mode, a light-emitting device using the organic compound described in embodiment mode 1 will be described with reference to fig. 1A to 1E.

Basic Structure of light emitting device

First, a basic structure of the light emitting device is explained. Fig. 1A shows an example of a light-emitting device having an EL layer including a light-emitting layer between a pair of electrodes. Specifically, the light-emitting device has a structure in which the EL layer 103 is sandwiched between the first electrode 101 and the second electrode 102.

Fig. 1B shows an example of a light-emitting device having a stacked-layer structure (series structure) of a plurality of (two layers in fig. 1B) EL layers (103a and 103B) between a pair of electrodes and a charge generation layer 104 between the EL layers. The EL layers to be stacked do not need to be two layers, and may be three or more layers.

The charge generation layer 104 has the following functions: when a voltage is applied to the first electrode 101 and the second electrode 102, electrons are injected into one EL layer (103a or 103b) and holes are injected into the other EL layer (103b or 103 a). Thus, in fig. 1B, when a voltage is applied so that the potential of the first electrode 101 is higher than that of the second electrode 102, the charge generation layer 104 injects electrons into the EL layer 103a and injects holes into the EL layer 103B.

In addition, from the viewpoint of light extraction efficiency, the charge generation layer 104 preferably has a light-transmitting property with respect to visible light (specifically, the visible light transmittance of the charge generation layer 104 is 40% or more). In addition, the charge generation layer 104 can function even if it has lower conductivity than the first electrode 101 or the second electrode 102.

Fig. 1C shows an example of a case where the EL layer 103 shown in fig. 1A (the same applies to a case where the EL layers (103a and 103B) in fig. 1B have a stacked structure) has a stacked structure. Note that in this case, the first electrode 101 is used as an anode. The EL layer 103 has a structure in which a hole injection layer 111, a hole transport layer 112, a light-emitting layer 113, an electron transport layer 114, and an electron injection layer 115 are sequentially stacked over the first electrode 101. In the case where a plurality of EL layers are provided as in the tandem structure shown in fig. 1B, the EL layers are also stacked from the anode side as shown in fig. 1D. In fig. 1D, each EL layer includes a hole injection layer (111a, 111b), a hole transport layer (112a, 112b), a light emitting layer (113a, 113b), an electron transport layer (114a, 114b), and an electron injection layer (115a, 115 b). In addition, when the first electrode 101 is a cathode and the second electrode 102 is an anode, the order of stacking the EL layers is reversed.

The light-emitting layer 113 in the EL layers (103, 103a, and 103b) can be formed by appropriately combining a light-emitting substance and a plurality of substances, and can obtain fluorescent light emission and phosphorescent light emission which show desired light emission colors. The light-emitting layer 113 may have a stacked structure with different emission colors. In this case, different materials may be used for the light-emitting substance and the other substance used in each of the stacked light-emitting layers. Further, a structure in which different emission colors are obtained from the plurality of EL layers (103a and 103B) shown in fig. 1B may be employed. In this case, different materials may be used for the light-emitting substance and the other substance used in each light-emitting layer. In addition, an organic compound according to one embodiment of the present invention can be used for the light-emitting layer 113.

In addition, in the light-emitting device according to one embodiment of the present invention, light obtained in the EL layers (103, 103a, 103b) may be resonated between electrodes, and the obtained light may be enhanced. For example, in fig. 1C, by making the first electrode 101 a reflective electrode and the second electrode 102 a semi-transmissive-semi-reflective electrode, an optical microcavity resonator (microcavity) structure is formed, whereby light obtained from the EL layer 103 can be enhanced.

In the case where the first electrode 101 of the light-emitting device is a reflective electrode having a stacked-layer structure of a conductive material having reflectivity and a conductive material having light transmittance (a transparent conductive film), optical adjustment can be performed by controlling the thickness of the transparent conductive film. Specifically, the adjustment is preferably performed as follows: when the wavelength of light obtained from the light-emitting layer 113 is λ, the distance between the first electrode 101 and the second electrode 102 is about m λ/2 (note that m is a natural number).

In order to amplify the desired light (wavelength: λ) obtained from the light-emitting layer 113, it is preferable to adjust the following: the optical distance from the first electrode 101 to the region (light-emitting region) of the light-emitting layer 113 where desired light can be obtained and the optical distance from the second electrode 102 to the region (light-emitting region) of the light-emitting layer 113 where desired light can be obtained are both (2m '+ 1) λ/4 (note that m' is a natural number). Note that the "light-emitting region" described here refers to a recombination region of holes and electrons in the light-emitting layer 113.

By performing the optical adjustment, the spectrum of the specific monochromatic light obtained from the light-emitting layer 113 can be narrowed, and light emission with good color purity can be obtained.

In addition, in the above case, strictly speaking, the optical distance between the first electrode 101 and the second electrode 102 can be said to be the total thickness from the reflective region in the first electrode 101 to the reflective region in the second electrode 102. However, since it is difficult to accurately determine the position of the reflective region in the first electrode 101 or the second electrode 102, the above-described effects can be sufficiently obtained by assuming that any position of the first electrode 101 and the second electrode 102 is the reflective region. In addition, strictly speaking, the optical distance between the first electrode 101 and the light-emitting layer that can obtain desired light can be said to be the optical distance between the reflective region in the first electrode 101 and the light-emitting region in the light-emitting layer that can obtain desired light. However, since it is difficult to accurately determine the position of the reflective region in the first electrode 101 or the light-emitting region in the light-emitting layer from which desired light can be obtained, the above-described effects can be sufficiently obtained by assuming that an arbitrary position in the first electrode 101 is the reflective region and an arbitrary position in the light-emitting layer from which desired light can be obtained is the light-emitting region.

The light emitting device shown in fig. 1C has a microcavity structure, and thus light of different wavelengths (monochromatic light) can be extracted even with the same EL layer. Thus, separate coating (e.g., R, G, B) is not required to obtain different emission colors, and high resolution can be achieved. In addition, it may be combined with a colored layer (color filter). Further, the emission intensity in the front direction having a specific wavelength can be enhanced, and low power consumption can be achieved.

The light-emitting device shown in fig. 1E is an example of the light-emitting device having a stacked structure (series structure) shown in fig. 1B, and has a structure in which three EL layers (103a, 103B, and 103c) are stacked with charge generation layers (104a and 104B) interposed therebetween, as shown in the drawing. The three EL layers (103a, 103b, 103c) include light-emitting layers (113a, 113b, 113c), respectively, and the emission colors of the light-emitting layers can be freely combined. For example, the light-emitting

layers

113a and 113c may be blue, and the light-emitting layer 113b may be one of red, green, and yellow. For example, the light-emitting

layers

113a and 113c may be red, and the light-emitting layer 113b may be blue, green, or yellow.

In the light-emitting device according to the above-described one embodiment of the present invention, at least one of the first electrode 101 and the second electrode 102 is an electrode having light-transmitting properties (e.g., a transparent electrode, a semi-transmissive and semi-reflective electrode, etc.). When the electrode having light transmittance is a transparent electrode, the visible light transmittance of the transparent electrode is 40% or more. In the case where the electrode is a semi-transmissive-semi-reflective electrode, the visible light reflectance of the semi-transmissive-semi-reflective electrode is 20% or more and 80% or less, and preferably 40% or more and 70% or less. In addition, the resistivity of these electrodes is preferably 1 × 10^-2Omega cm or less.

In the light-emitting device according to the above-described one embodiment of the present invention, when one of the first electrode 101 and the second electrode 102 is a reflective electrode (reflective electrode), the visible light reflectance of the reflective electrode is 40% or more and 100% or less, and preferably 70% or more and 100% or less. In addition, the resistivity of the electrode is preferably 1 × 10^-2Omega cm or less.

Detailed structure and manufacturing method of light emitting device

Next, a specific structure and a manufacturing method of the light-emitting device shown in fig. 1A to 1E, which are one embodiment of the present invention, will be described. Here, not only a light-emitting device having the EL layer 103 shown in fig. 1A and 1C with a single-layer structure but also a light-emitting device having a series structure shown in fig. 1B, 1D, and 1E will be described. In the case where each of the light-emitting devices shown in fig. 1A to 1E has a microcavity structure, for example, a reflective electrode may be formed as the first electrode 101, and a semi-transmissive-semi-reflective electrode may be formed as the second electrode 102. Thus, the electrode can be formed by using a desired electrode material alone or by using a plurality of desired electrode materials in a single layer or a stacked layer. After the EL layers (103, 103b) are formed, the second electrode 102 is formed by selecting the material in the same manner as described above. The electrode may be formed by a sputtering method or a vacuum deposition method.

First and second electrodes >

As materials for forming the first electrode 101 and the second electrode 102, the following materials may be appropriately combined if the functions of the two electrodes can be satisfied. For example, metals, alloys, conductive compounds, mixtures thereof, and the like can be suitably used. Specific examples thereof include an In-Sn oxide (also referred to as ITO), an In-Si-Sn oxide (also referred to as ITSO), an In-Zn oxide, and an In-W-Zn oxide. In addition to the above, metals such as aluminum (Al), titanium (Ti), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), gallium (Ga), zinc (Zn), indium (In), tin (Sn), molybdenum (Mo), tantalum (Ta), tungsten (W), palladium (Pd), gold (Au), platinum (Pt), silver (Ag), yttrium (Y), neodymium (Nd), and alloys appropriately combining these metals may be mentioned. In addition to the above, elements belonging to group 1 or group 2 of the periodic table (for example, rare earth metals such as lithium (Li), cesium (Cs), calcium (Ca), strontium (Sr)), europium (Eu), ytterbium (Yb), etc., alloys in which these are appropriately combined, graphene, and the like can be used.

In the case where the light-emitting device shown in fig. 1A to 1E includes the EL layer 103 having the stacked-layer structure shown in fig. 1C and the first electrode 101 serving as an anode, the hole injection layer 111 and the hole transport layer 112 of the EL layer 103 are sequentially stacked on the first electrode 101 by a vacuum evaporation method. Further, as shown in fig. 1D, when a plurality of EL layers (103a, 103b) having a stacked structure are stacked with the charge generation layer 104 interposed therebetween and the first electrode 101 is an anode, the hole injection layer 111a and the hole transport layer 112a of the EL layer 103a are sequentially stacked on the first electrode 101 by a vacuum evaporation method, and after the EL layer 103a and the charge generation layer 104 are sequentially stacked, the hole injection layer 111b and the hole transport layer 112b of the EL layer 103b are sequentially stacked on the charge generation layer 104 in the same manner as described above.

< hole injection layer and hole transport layer >

The hole injection layers (111, 111a, 111b) are layers for injecting holes from the first electrode 101 or the charge generation layer (104) of the anode into the EL layers (103, 103a, 103b), and include a material having a high hole injection property.

Examples of the material having a high hole-injecting property include transition metal oxides such as molybdenum oxide, vanadium oxide, ruthenium oxide, tungsten oxide, and manganese oxide. In addition to the above, phthalocyanine-based compounds such as phthalocyanine (abbreviated as H) can be used₂Pc), copper phthalocyanine (CuPc), and the like.

In addition, aromatic amine compounds of low-molecular compounds such as 4,4 '-tris (N, N-diphenylamino) triphenylamine (abbreviated as TDATA), 4' -tris [ N- (3-methylphenyl) -N-phenylamino ] triphenylamine (abbreviated as MTDATA), 4 '-bis [ N- (4-diphenylaminophenyl) -N-phenylamino ] biphenyl (abbreviated as DPAB), 4' -bis (N- {4- [ N '- (3-methylphenyl) -N' -phenylamino ] phenyl } -N-phenylamino) biphenyl (abbreviated as DNTPD), 1,3, 5-tris [ N- (4-diphenylaminophenyl) -N-phenylamino ] benzene (abbreviated as DPA3B), and the like can be used, 3- [ N- (9-phenylcarbazol-3-yl) -N-phenylamino ] -9-phenylcarbazole (abbreviated as PCzPCA1), 3, 6-bis [ N- (9-phenylcarbazol-3-yl) -N-phenylamino ] -9-phenylcarbazole (abbreviated as PCzPCA2), 3- [ N- (1-naphthyl) -N- (9-phenylcarbazol-3-yl) amino ] -9-phenylcarbazole (abbreviated as PCzPCN1), and the like.

In addition, high molecular compounds (oligomers, dendrimers, polymers, etc.) such as Poly (N-vinylcarbazole) (abbreviated as PVK), Poly (4-vinyltriphenylamine) (abbreviated as PVTPA), Poly [ N- (4- { N '- [4- (4-diphenylamino) phenyl ] phenyl-N' -phenylamino } phenyl) methacrylamide ] (abbreviated as PTPDMA), Poly [ N, N '-bis (4-butylphenyl) -N, N' -bis (phenyl) benzidine ] (abbreviated as Poly-TPD), etc. can be used. Alternatively, a polymer compound to which an acid is added, such as poly (3, 4-ethylenedioxythiophene)/poly (styrenesulfonic acid) (abbreviated as PEDOT/PSS) or polyaniline/poly (styrenesulfonic acid) (PANI/PSS), may also be used.

As the material having a high hole-injecting property, a composite material including a hole-transporting material and an acceptor material (electron acceptor material) may be used. In this case, electrons are extracted from the hole-transporting material by the acceptor material, holes are generated in the hole-injecting layers (111, 111a, 111b), and the holes are injected into the light-emitting layers (113, 113a, 113b) through the hole-transporting layers (112, 112a, 112 b). The hole injection layers (111, 111a, and 111b) may be formed of a single layer of a composite material including a hole-transporting material and an acceptor material (electron acceptor material), or may be formed of a stack of layers formed using a hole-transporting material and an acceptor material (electron acceptor material).

The hole transport layers (112, 112a, 112b) are layers that transport holes injected from the first electrode 101 through the hole injection layers (111, 111a, 111b) into the light emitting layers (113, 113a, 113 b). The hole-transporting layer (112, 112a, 112b) is a layer containing a hole-transporting material. As the hole-transporting material used for the hole-transporting layers (112, 112a, 112b), a material having the HOMO energy level that is the same as or close to the HOMO energy level of the hole-injecting layers (111, 111a, 111b) is particularly preferably used.

As an acceptor material for the hole injection layer (111, 111a, 111b), an oxide of a metal belonging to groups 4 to 8 in the periodic table of elements can be used. Specific examples thereof include molybdenum oxide, vanadium oxide, niobium oxide, tantalum oxide, chromium oxide, tungsten oxide, manganese oxide, and rhenium oxide. Molybdenum oxide is particularly preferably used because it is also stable in the atmosphere, has low hygroscopicity, and is easy to handle. In addition to the above, examples include organic acceptors such as quinodimethane derivatives, tetrachlorobenzoquinone derivatives, and hexaazatriphenylene derivatives. As the above-mentioned compound having an electron-withdrawing group (halogeno or cyano group), there may be mentionedExamples thereof include 7, 7, 8, 8-tetracyano-2, 3,5, 6-tetrafluoroquinodimethane (abbreviated as F)₄TCNQ), chloranil, 2,3, 6, 7, 10, 11-hexacyan-1, 4, 5, 8,9, 12-hexaazatriphenylene (abbreviation: HAT-CN), 1,3,4, 5, 7, 8-hexafluorotetracyano (hexafluoroacetonitrile) -naphthoquinone dimethane (naphthoquinodimethane) (abbreviation: F6-TCNNQ), and the like. In particular, a compound in which a condensed aromatic ring having a plurality of hetero atoms such as HAT-CN is bonded to an electron-withdrawing group is preferable because it is thermally stable. Further, [ 3] comprising an electron-withdrawing group (particularly, a halogen group such as a fluoro group, a cyano group)]The axine derivative is particularly preferable because it has a very high electron-accepting property. Specifically, there may be mentioned: alpha, alpha' -1,2, 3-cyclopropane triylidene tris [ 4-cyano-2, 3,5, 6-tetrafluorophenylacetonitrile]Alpha, alpha' -1,2, 3-cyclopropane triylidenetris [2, 6-dichloro-3, 5-difluoro-4- (trifluoromethyl) benzeneacetonitrile]Alpha, alpha' -1,2, 3-cyclopropane triylidene tris [2, 3,4, 5, 6-pentafluorophenylacetonitrile]And the like.

The hole-transporting material used for the hole-injecting layers (111, 111a, 111b) and the hole-transporting layers (112, 112a, 112b) is preferably one that is applied at an electric field strength [ V/cm ]]Has a square root of 1 × 10 when it is 600^-6cm²A substance having a hole mobility of greater than/Vs. In addition, any substance other than the above may be used as long as it has a hole-transporting property higher than an electron-transporting property.

The hole-transporting material is preferably a material having high hole-transporting property, such as a pi-electron-rich heteroaromatic compound (e.g., carbazole derivative or furan derivative) or an aromatic amine (compound having an aromatic amine skeleton).

Examples of the carbazole derivative (compound having a carbazole skeleton) include a biscarbazole derivative (for example, 3, 3' -biscarbazole derivative), an aromatic amine having a carbazole group, and the like.

Specific examples of the bicarbazole derivative (for example, 3,3 '-bicarbazole derivative) include 3, 3' -bis (9-phenyl-9H-carbazole) (PCCP), 9 '-bis (1, 1' -biphenyl-4-yl) -3,3 '-bi-9H-carbazole, 9' -bis (1,1 '-biphenyl-3-yl) -3, 3' -bi-9H-carbazole, 9- (1,1 '-biphenyl-3-yl) -9' - (1,1 '-biphenyl-4-yl) -9H, 9' H-3,3 '-bicarbazole (mBPCCBP), 9- (2-naphthyl) -9' -phenyl-9H, 9 'H-3, 3' -bicarbazole (abbreviated as. beta. NCCP), and the like.

Specific examples of the aromatic amine having a carbazole group include 4-phenyl-4 '- (9-phenyl-9H-carbazol-3-yl) triphenylamine (abbreviated to PCBA1BP), N- (4-biphenyl) -N- (9, 9-dimethyl-9H-fluoren-2-yl) -9-phenyl-9H-carbazol-3-amine (abbreviated to pcpef), N- (1, 1' -biphenyl-4-yl) -N- [4- (9-phenyl-9H-carbazol-3-yl) phenyl ] -9, 9-dimethyl-9H-fluoren-2-amine (abbreviated to PCBBiF), and 4,4 ' -diphenyl-4 ' - (9-phenyl-9H-carbazol-3-yl) triphenylamine (abbreviated as PCBBi1BP), 4- (1-naphthyl) -4 ' - (9-phenyl-9H-carbazol-3-yl) triphenylamine (abbreviated as PCBANB), 4 ' -bis (1-naphthyl) -4 ' - (9-phenyl-9H-carbazol-3-yl) triphenylamine (abbreviated as PCBNBB), 4-phenyldiphenyl- (9-phenyl-9H-carbazol-3-yl) amine (abbreviated as PCA1BP), N ' -bis (9-phenylcarbazol-3-yl) -N, N ' -diphenylbenzene-1, 3-diamine (PCA 2B), N ' -triphenyl-N, N ' -tris (9-phenylcarbazol-3-yl) benzene-1, 3, 5-triamine (PCA 3B), 9-dimethyl-N-phenyl-N- [4- (9-phenyl-9H-carbazol-3-yl) phenyl ] fluorene-2-amine (PCBAF), N-phenyl-N- [4- (9-phenyl-9H-carbazol-3-yl) phenyl ] spiro-9, 9 ' -bifluorene-2-amine (PCBASF), 3- [ N- (9-phenylcarbazol-3-yl) -N-phenylamino ] -9-phenylcarbazole (PCA 1), 3, 6-bis [ N- (9-phenylcarbazol-3-yl) -N-phenylamino ] -9-phenylcarbazole (abbreviation: PCzPCA2), 3- [ N- (1-naphthyl) -N- (9-phenylcarbazol-3-yl) amino ] -9-phenylcarbazole (abbreviation: PCzPCN1), 3- [ N- (4-diphenylaminophenyl) -N-phenylamino ] -9-phenylcarbazole (abbreviation: PCzDPA1), 3, 6-bis [ N- (4-diphenylaminophenyl) -N-phenylamino ] -9-phenylcarbazole (abbreviation: PCzDPA2), 3, 6-bis [ N- (4-diphenylaminophenyl) -N- (1-naphthyl) amino ] -9-phenylcarbazole (abbreviation: PCzTPN2) ) 2- [ N- (9-phenylcarbazol-3-yl) -N-phenylamino ] spiro-9, 9' -bifluorene (abbreviation: PCASF), N- [4- (9H-carbazol-9-yl) phenyl ] -N- (4-phenyl) phenylaniline (abbreviation: YGA1BP), N '-bis [4- (carbazol-9-yl) phenyl ] -N, N' -diphenyl-9, 9-dimethylfluorene-2, 7-diamine (abbreviation: YGA2F), 4', 4 ″ -tris (carbazol-9-yl) triphenylamine (abbreviation: TCTA), and the like.

As the carbazole derivative, in addition to the above, examples thereof include 3- [4- (9-phenanthryl) -phenyl ] -9-phenyl-9H-carbazole (abbreviated as PCPPn), 3- [4- (1-naphthyl) -phenyl ] -9-phenyl-9H-carbazole (abbreviated as PCPN), 1, 3-bis (N-carbazolyl) benzene (abbreviated as mCP), 4' -bis (N-carbazolyl) biphenyl (abbreviated as CBP), 3, 6-bis (3, 5-diphenylphenyl) -9-phenylcarbazole (abbreviated as CZTP), 1,3, 5-tris [4- (N-carbazolyl) phenyl ] benzene (abbreviated as TCPB), 9- [4- (10-phenyl-9-anthracyl) phenyl ] -9H-carbazole (abbreviated as CZPA) and the like.

Specific examples of the furan derivative (compound having a furan skeleton) include compounds having a thiophene skeleton such as 4,4 ', 4 "- (benzene-1, 3, 5-triyl) tris (dibenzothiophene) (abbreviated as DBT3P-II), 2, 8-diphenyl-4- [4- (9-phenyl-9H-fluoren-9-yl) phenyl ] dibenzothiophene (abbreviated as DBTFLP-III), 4- [4- (9-phenyl-9H-fluoren-9-yl) phenyl ] -6-phenyldibenzothiophene (abbreviated as DBTFLP-IV), and 4, 4', 4" - (benzene-1, 3, 5-triyl) tris (dibenzofuran) (abbreviated as DBF3P-II), 4- {3- [3- (9-phenyl-9H-fluoren-9-yl) phenyl ] phenyl } dibenzofuran (mmDBFFLBi-II).

Specific examples of the aromatic amine include 4,4 ' -bis [ N- (1-naphthyl) -N-phenylamino ] biphenyl (abbreviated as NPB or. alpha. -NPD), N ' -bis (3-methylphenyl) -N, N ' -diphenyl- [1,1 ' -biphenyl ] -4,4 ' -diamine (abbreviated as TPD), 4 ' -bis [ N- (spiro-9, 9 ' -difluoren-2-yl) -N-phenylamino ] biphenyl (abbreviated as BSPB), 4-phenyl-4 ' - (9-phenylfluoren-9-yl) triphenylamine (abbreviated as BPAFLP), 4-phenyl-3 ' - (9-phenylfluoren-9-yl) triphenylamine (abbreviated as mBPAFLP), N- (9, 9-dimethyl-9H-fluoren-2-yl) -N- {9, 9-dimethyl-2- [ N ' -phenyl-N ' - (9, 9-dimethyl-9H-fluoren-2-yl) amino ] -9H-fluoren-7-yl } phenylamine (abbreviated: DFLADFL), N- (9, 9-dimethyl-2-diphenylamino-9H-fluoren-7-yl) diphenylamine (abbreviated: DPNF), 2- [ N- (4-diphenylaminophenyl) -N-phenylamino ] spiro-9, 9 ' -bifluorene (abbreviated: DPASF), 2, 7-bis [ N- (4-diphenylaminophenyl) -N-phenylamino ] spiro-9, 9 ' -bifluorene (abbreviated as DPA2SF), 4 ' -tris [ N- (1-naphthyl) -N-phenylamino ] triphenylamine (abbreviated as 1 ' -TNATA), 4 ' -tris (N, N-diphenylamino) triphenylamine (abbreviated as TDATA), 4 ' -tris [ N- (3-methylphenyl) -N-phenylamino ] triphenylamine (abbreviated as m-MTDATA), N ' -bis (p-tolyl) -N, N ' -diphenyl-p-phenylenediamine (abbreviated as DTDPPA), 4 ' -bis [ N- (4-diphenylaminophenyl) -N-phenylamino ] biphenyl (abbreviated as DPAB), N ' -bis {4- [ bis (3-methylphenyl) amino ] phenyl } -N, n ' -diphenyl- (1,1 ' -biphenyl) -4,4 ' -diamine (abbreviated as DNTPD), 1,3, 5-tris [ N- (4-diphenylaminophenyl) -N-phenylamino ] benzene (abbreviated as DPA3B), and the like.

As the hole transporting material, a polymer compound such as Poly (N-vinylcarbazole) (abbreviated as PVK), Poly (4-vinyltriphenylamine) (abbreviated as PVTPA), Poly [ N- (4- { N '- [4- (4-diphenylamino) phenyl ] phenyl-N' -phenylamino } phenyl) methacrylamide ] (abbreviated as PTPDMA), Poly [ N, N '-bis (4-butylphenyl) -N, N' -bis (phenyl) benzidine ] (abbreviated as Poly-TPD) or the like can be used.

Note that the hole-transporting material is not limited to the above-described materials, and one or a combination of a plurality of known materials can be used as the hole-transporting material for the hole injection layers (111, 111a, 111b) and the hole transport layers (112, 112a, 112 b). The hole transport layers (112, 112a, 112b) may be formed of a plurality of layers. That is, for example, the first hole transport layer and the second hole transport layer may be stacked.

In the light-emitting device shown in fig. 1A to 1E, the light-emitting layer (113, 113a) is formed on the hole-transporting layer (112, 112a) in the EL layer (103, 103a) by a vacuum evaporation method. In the case of the light-emitting device having the tandem structure shown in fig. 1D, after the EL layer 103a and the charge generation layer 104 are formed, the light-emitting layer 113b is formed on the hole transport layer 112b in the EL layer 103b by a vacuum evaporation method.

< light-emitting layer >

The light-emitting layers (113, 113a, 113b, 113c) are layers containing a light-emitting substance. As the light-emitting substance, a substance exhibiting a light-emitting color such as blue, violet, bluish-violet, green, yellowish green, yellow, orange, or red is suitably used. Further, by using different light-emitting substances for each of the plurality of light-emitting layers (113a, 113b, and 113c), different light-emitting colors can be obtained (for example, white light can be obtained by combining light-emitting colors in a complementary color relationship). Further, a stacked structure in which one light-emitting layer includes different light-emitting substances may be employed.

The light-emitting layers (113, 113a, 113b, and 113c) may contain one or more organic compounds (host materials, etc.) in addition to the light-emitting substance (guest material). As the one or more kinds of organic compounds, one or both of the organic compound of one embodiment of the present invention, the hole-transporting material and the electron-transporting material described in this embodiment can be used.

The light-emitting substance that can be used for the light-emitting layers (113, 113a, 113b, and 113c) is not particularly limited, and a light-emitting substance that converts singlet excitation energy into light in the visible light region or a light-emitting substance that converts triplet excitation energy (energy difference between the base state and the triplet excited state) into light in the visible light region can be used.

Examples of the other luminescent materials include the following.

Examples of the light-emitting substance which converts a single excitation energy into light emission include substances which emit fluorescence (fluorescent materials), and examples thereof include pyrene derivatives, anthracene derivatives, triphenylene derivatives, fluorene derivatives, carbazole derivatives, dibenzothiophene derivatives, dibenzofuran derivatives, dibenzoquinoxaline derivatives, quinoxaline derivatives, pyridine derivatives, pyrimidine derivatives, phenanthrene derivatives, and naphthalene derivatives. In particular, the pyrene derivative is preferable because the luminescence quantum yield is high. Specific examples of the pyrene derivative include N, N ' -bis (3-methylphenyl) -N, N ' -bis [3- (9-phenyl-9H-fluoren-9-yl) phenyl ] pyrene-1, 6-diamine (abbreviated as 1, 6mMemFLPAPRn), N ' -diphenyl-N, N ' -bis [4- (9-phenyl-9H-fluoren-9-yl) phenyl ] pyrene-1, 6-diamine (abbreviated as 1, 6FLPAPRn), N ' -bis (dibenzofuran-2-yl) -N, N ' -diphenylpyrene-1, 6-diamine (abbreviated as 1, 6FrAPrn), N ' -bis (dibenzothiophene-2-yl) -N, n '-Diphenylpyrene-1, 6-diamine (abbreviated as 1, 6ThAPrn), N' - (pyrene-1, 6-diyl) bis [ (N-phenylbenzo [ b ] naphtho [1,2-d ] furan) -6-amine ] (abbreviated as 1, 6BnfAPrn), N '- (pyrene-1, 6-diyl) bis [ (N-phenylbenzo [ b ] naphtho [1,2-d ] furan) -8-amine ] (abbreviated as 1, 6BnfAPrn-02), N' - (pyrene-1, 6-diyl) bis [ (6, N-diphenylbenzo [ b ] naphtho [1,2-d ] furan) -8-amine ] (abbreviated as 1, 6BnfAPrn-03), and the like.

In addition to the above, 5, 6-bis [4- (10-phenyl-9-anthracenyl) phenyl ] -2, 2 '-bipyridine (abbreviated as PAP2BPy), 5, 6-bis [ 4' - (10-phenyl-9-anthracenyl) biphenyl-4-yl ] -2, 2 '-bipyridine (abbreviated as PAPP2BPy), N' -bis [4- (9H-carbazol-9-yl) phenyl ] -N, N '-diphenylstilbene-4, 4' -diamine (abbreviated as YGA2S), 4- (9H-carbazol-9-yl) -4 '- (10-phenyl-9-anthracenyl) triphenylamine (abbreviated as YGAPA), 4- (9H-carbazol-9-yl) -4' - (9H-carbazol-9-yl) triphenylamine (abbreviated as YGAPA), 10-diphenyl-2-anthryl) triphenylamine (abbreviation: 2YGAPPA), N, 9-diphenyl-N- [4- (10-phenyl-9-anthracenyl) phenyl ] -9H-carbazol-3-amine (abbreviation: PCAPA), 4- (10-phenyl-9-anthracenyl) -4' - (9-phenyl-9H-carbazol-3-yl) triphenylamine (abbreviation: PCBAPA), 4- [4- (10-phenyl-9-anthracenyl) phenyl ] -4' - (9-phenyl-9H-carbazol-3-yl) triphenylamine (abbreviation: pcbappaba), perylene, 2, 5, 8, 11-tetra- (tert-butyl) perylene (abbreviation: TBP), N ″ - (2-tert-butylanthracene-9, 10-diylbis-4, 1-phenylene) bis [ N, N' -triphenyl-1, 4-phenylenediamine ] (abbreviation: DPABPA), N, 9-diphenyl-N- [4- (9, 10-diphenyl-2-anthracenyl) phenyl ] -9H-carbazol-3-amine (abbreviation: 2PCAPPA), N- [4- (9, 10-diphenyl-2-anthryl) phenyl ] -N, N' -triphenyl-1, 4-phenylenediamine (abbreviation: 2DPAPPA), and the like.

Examples of the light-emitting substance which converts triplet excitation energy into light emission include a substance which emits phosphorescence (phosphorescent material) and a Thermally Activated Delayed Fluorescence (TADF) material which exhibits Thermally activated delayed fluorescence.

Examples of the phosphorescent material include an organometallic complex, a metal complex (platinum complex), a rare earth metal complex, and the like. Such substances exhibit different emission colors (emission peaks), and are selected and used as needed.

The following can be mentioned as examples of phosphorescent materials which exhibit blue or green color and have an emission spectrum with a peak wavelength of 450nm to 570 nm.

For example, tris {2- [5- (2-methylbenzene)Yl) -4- (2, 6-dimethylphenyl) -4H-1, 2, 4-triazol-3-yl-kappa N2]Phenyl-kappa C iridium (III) (abbreviation: [ Ir (mpptz-dmp) ]₃]) Tris (5-methyl-3, 4-diphenyl-4H-1, 2, 4-triazole) iridium (III) (abbreviation: [ Ir (Mptz)₃]) Tris [4- (3-biphenyl) -5-isopropyl-3-phenyl-4H-1, 2, 4-triazole]Iridium (III) (abbreviation: [ Ir (iPrptz-3b)₃]) Tris [3- (5-biphenyl) -5-isopropyl-4-phenyl-4H-1, 2, 4-triazole]Iridium (III) (abbreviation: [ Ir (iPr5btz)₃]) And organometallic complexes having a 4H-triazole skeleton; tris [ 3-methyl-1- (2-methylphenyl) -5-phenyl-1H-1, 2, 4-triazole]Iridium (III) (abbreviation: [ Ir (Mptz1-mp)₃]) Tris (1-methyl-5-phenyl-3-propyl-1H-1, 2, 4-triazole) iridium (III) (abbreviation: [ Ir (Prptz1-Me)₃]) And the like organometallic complexes having a 1H-triazole skeleton; fac-tris [1- (2, 6-diisopropylphenyl) -2-phenyl-1H-imidazole]Iridium (III) (abbreviation: [ Ir (iPrpmi)₃]) Tris [3- (2, 6-dimethylphenyl) -7-methylimidazo [1, 2-f ]]Phenanthridino (phenanthrinato)]Iridium (III) (abbreviation: [ Ir (dmpimpt-Me)₃]) And the like organic metal complexes having an imidazole skeleton; and bis [2- (4 ', 6' -difluorophenyl) pyridinato-N, C^2’]Iridium (III) tetrakis (1-pyrazolyl) borate (FIr 6 for short), bis [2- (4 ', 6' -difluorophenyl) pyridinato-N, C^2’]Iridium (III) picolinate (FIrpic), bis {2- [3 ', 5' -bis (trifluoromethyl) phenyl]pyridinato-N, C^2’Iridium (III) picolinate (abbreviation: [ Ir (CF)₃ppy)₂(pic)]) Bis [2- (4 ', 6' -difluorophenyl) pyridinato-N, C^2’]Organometallic complexes in which an electron-withdrawing group-containing phenylpyridine derivative is a ligand, such as iridium (III) acetylacetonate (FIr (acac)).

The phosphorescent material exhibiting green or yellow color and having an emission spectrum with a peak wavelength of 495nm or more and 590nm or less includes the following materials.

For example, tris (4-methyl-6-phenylpyrimidine) iridium (III) (abbreviation: [ Ir (mppm))₃]) Tris (4-tert-butyl-6-phenylpyrimidine) iridium (III) (abbreviation: [ Ir (tBuppm)₃]) And (acetylacetonate) bis (6-methyl-4-phenylpyrimidine) iridium (III) (abbreviation: [ Ir (mppm)₂(acac)]) And (acetylacetonate) bis (6-tert-butyl-4-phenylpyrimidine) iridium (III) (abbreviation: [ Ir (tBuppm)₂(acac)]) (Acetylacetonate) bis [6- (2-norbornyl) -4-phenylpyrimidine]Iridium (III) (abbreviation: [ Ir (nbppm)₂(acac)]) (Acetylacetonate) bis [ 5-methyl-6- (2-methylphenyl) -4-phenylpyrimidine]Iridium (III) (abbreviation: [ Ir (mpmppm))₂(acac)]) (Acetylacetonate) bis {4, 6-dimethyl-2- [6- (2, 6-dimethylphenyl) -4-pyrimidinyl-. kappa.N 3]Phenyl-. kappa.C } Iridium (III) (abbreviation: [ Ir (dmppm-dmp) ]₂(acac)]) And (acetylacetonate) bis (4, 6-diphenylpyrimidine) iridium (III) (abbreviation: [ Ir (dppm)₂(acac)]) And the like organometallic iridium complexes having a pyrimidine skeleton; (Acetylacetonato) bis (3, 5-dimethyl-2-phenylpyrazine) Iridium (III) (abbreviation: [ Ir (mppr-Me)₂(acac)]) And (acetylacetonate) bis (5-isopropyl-3-methyl-2-phenylpyrazine) iridium (III) (abbreviation: [ Ir (mppr-iPr)₂(acac)]) And the like organometallic iridium complexes having a pyrazine skeleton; tris (2-phenylpyridinato-N, C)^2’) Iridium (III) (abbreviation: [ Ir (ppy)₃]) Bis (2-phenylpyridinato-N, C)^2’) Iridium (III) acetylacetone (abbreviation: [ Ir (ppy)₂(acac)]) Bis (benzo [ h ]]Quinoline) iridium (III) acetylacetone (abbreviation: [ Ir (bzq)₂(acac)]) Tris (benzo [ h ]) or a salt thereof]Quinoline) iridium (III) (abbreviation: [ Ir (bzq)₃]) Tris (2-phenylquinoline-N, C)^2’) Iridium (III) (abbreviation: [ Ir (pq)₃]) Bis (2-phenylquinoline-N, C)^2’) Iridium (III) acetylacetone (abbreviation: [ Ir (pq)₂(acac)]) Bis [2- (2-pyridyl-. kappa.N) phenyl-. kappa.C][2- (4-phenyl-2-pyridyl-. kappa.N) phenyl-. kappa.C]Iridium (III) (abbreviation: [ Ir (ppy)₂(4dppy)]) Bis [2- (2-pyridyl-. kappa.N) phenyl-. kappa.C][2- (4-methyl-5-phenyl-2-pyridyl-. kappa.N) phenyl-. kappa.C]And the like organometallic iridium complexes having a pyridine skeleton; bis (2, 4-diphenyl-1, 3-oxazole-N, C^2’) Iridium (III) acetylacetone (abbreviation: [ Ir (dpo)₂(acac)]) Bis {2- [ 4' - (perfluorophenyl) phenyl]pyridine-N, C^2’Iridium (III) acetylacetone (abbreviation [ Ir (p-PF-ph)₂(acac)]) Bis (2-phenylbenzothiazole-N, C)^2’) Iridium (III) acetylacetone (abbreviation: [ Ir (bt)₂(acac)]) Isoorganometallic complexes, tris (acetylacetonate) (mono-phenanthrene)Roline) terbium (III) (abbreviation: [ Tb (acac)₃(Phen)]) And the like.

The following can be mentioned as examples of phosphorescent materials which exhibit yellow or red color and have an emission spectrum with a peak wavelength of 570nm to 750 nm.

For example, bis [4, 6-bis (3-methylphenyl) pyrimidino ] isobutyrylmethanoate]Iridium (III) (abbreviation: [ Ir (5mdppm)₂(dibm)]) Bis [4, 6-bis (3-methylphenyl) pyrimidino radical](Dipivaloylmethane) Iridium (III) (abbreviation: [ Ir (5 mddppm)₂(dpm)]) And (dipivaloylmethane) bis [4, 6-di (naphthalen-1-yl) pyrimidinium radical]Iridium (III) (abbreviation: [ Ir (d1npm)₂(dpm)]) And the like organic metal complexes having a pyrimidine skeleton; (acetylacetonato) bis (2, 3, 5-triphenylpyrazine) iridium (III) (abbreviation: [ Ir (tppr))₂(acac)]) Bis (2, 3, 5-triphenylpyrazine) (dipivaloylmethane) iridium (III) (abbreviation: [ Ir (tppr)₂(dpm)]) Bis {4, 6-dimethyl-2- [3- (3, 5-dimethylphenyl) -5-phenyl-2-pyrazinyl-. kappa.N]Phenyl-kappa C } (2, 6-dimethyl-3, 5-heptanedione-kappa)²O, O') iridium (III) (abbreviation: [ Ir (dmdppr-P)₂(dibm)]) Bis {4, 6-dimethyl-2- [5- (4-cyano-2, 6-dimethylphenyl) -3- (3, 5-dimethylphenyl) -2-pyrazinyl-. kappa.N]Phenyl- κ C } (2,2,6, 6-tetramethyl-3, 5-heptanedione- κ)²O, O') iridium (III) (abbreviation: [ Ir (dmdppr-dmCP)₂(dpm)]) (acetylacetone) bis [ 2-methyl-3-phenylquinoxalineato)]-N，C^2’]Iridium (III) (abbreviation: [ Ir (mpq))₂(acac)]) (acetylacetone) bis (2, 3-diphenylquinoxalineato) -N, C^2’]Iridium (III) (abbreviation: [ Ir (dpq))₂(acac)]) (acetylacetonato) bis [2, 3-bis (4-fluorophenyl) quinoxalato)]Iridium (III) (abbreviation: [ Ir (Fdpq)₂(acac)]) And the like organic metal complexes having a pyrazine skeleton; tris (1-phenylisoquinoline-N, C)^2’) Iridium (III) (abbreviation: [ Ir (piq)₃]) Bis (1-phenylisoquinoline-N, C)^2’) Iridium (III) acetylacetone (abbreviation: [ Ir (piq)₂(acac)]) Bis [4, 6-dimethyl-2- (2-quinoline-. kappa.N) phenyl-. kappa.C](2, 4-Pentanedionato-. kappa.)²O, O') iridium (III) and the like having a pyridine skeleton; 2,3,7,8, 12,13, 17, 18-Octaethyl-21H, 23H-porphyrin platinum (II) (abbreviation [ PtOEP ]]) And platinum complexes; and tris (1, 3-diphenyl-1, 3-propanedione (monophenanthroline) europium (III) (abbreviation: [ Eu (DBM))₃(Phen)]) Tris [1- (2-thenoyl) -3,3, 3-trifluoroacetone](Monophenanthroline) europium (III) (abbreviation: [ Eu (TTA))₃(Phen)]) And the like.

As the organic compound (host material or the like) used for the light-emitting layers (113, 113a, 113b, 113c), one or more kinds of substances having a larger energy gap than that of the light-emitting substance (guest material) can be selected.

Therefore, when the light-emitting substance used in the light-emitting layers (113, 113a, 113b, and 113c) is a fluorescent material, it is preferable to use an organic compound having a large singlet excited state and a small triplet excited state as an organic compound (host material) to be used in combination with the light-emitting substance. As the organic compound (host material) used in combination with the light-emitting substance, a bipolar material or the like can be used in addition to the organic compound according to one embodiment of the present invention described in embodiment 1, the hole-transporting material (described above) or the electron-transporting material (described below) described in this embodiment. By using the organic compound according to one embodiment of the present invention shown in embodiment mode 1 for the light-emitting layer (particularly, using the organic compound as a host material), initial deterioration of the light-emitting device can be suppressed, and reliability can be improved.

Although a part of the description overlaps with the above specific examples, specific examples of the organic compound are shown below from the viewpoint of preferable combination with a light-emitting substance (a fluorescent material or a phosphorescent material).

When the light-emitting substance is a fluorescent substance, examples of the organic compound (host material) which can be used in combination with the light-emitting substance include anthracene derivatives, tetracene derivatives, phenanthrene derivatives, pyrene derivatives, and the like,

(chrysene) derivatives, dibenzo [ g, p ]]

Derivatives, and the like. In addition, an organic compound according to one embodiment of the present invention shown in embodiment 1 is preferably used.

Specific examples of the organic compound (host material) used in combination with the fluorescent light-emitting substance include 9-phenyl-3- [4- (10-phenyl-9-anthryl) phenyl]-9H-carbazole (PCzPA), 3, 6-diphenyl-9- [4- (10-phenyl-9-anthryl) phenyl]-9H-carbazole (abbreviated as DPCzPA), 3- [4- (1-naphthyl) -phenyl]-9-phenyl-9H-carbazole (PCPN), 9, 10-diphenylanthracene (DPAnth), N-diphenyl-9- [4- (10-phenyl-9-anthryl) phenyl]-9H-carbazole-3-amine (CzA 1-1 PA), 4- (10-phenyl-9-anthryl) triphenylamine (DPhPA), YGAPA, PCAPA, N, 9-diphenyl-N- {4- [4- (10-phenyl-9-anthryl) phenyl]Phenyl } -9H-carbazole-3-amine (PCAPBA), N- (9, 10-diphenyl-2-anthryl) -N, 9-diphenyl-9H-carbazole-3-amine (2 PCAPA), 6, 12-dimethoxy-5, 11-diphenyl

N, N, N ', N ', N ", N", N ' "-octaphenyldibenzo [ g, p]

-2,7, 10, 15-tetramine (DBC 1 for short) and 9- [4- (10-phenyl-9-anthryl) phenyl]-9H-carbazole (CzPA), 7- [4- (10-phenyl-9-anthryl) phenyl]-7H-dibenzo [ c, g]Carbazole (short for: cgDBCzPA), 6- [3- (9, 10-diphenyl-2-anthryl) phenyl]-benzo [ b ]]Naphtho [1,2-d ]]Furan (abbreviation: 2mBnfPPA), 9-phenyl-10- {4- (9-phenyl-9H-fluoren-9-yl) -biphenyl-4 '-yl } -anthracene (abbreviation: FLPPA), 9, 10-bis (3, 5-diphenylphenyl) anthracene (abbreviation: DPPA), 9, 10-bis (2-naphthyl) anthracene (abbreviation: DNA), 2-tert-butyl-9, 10-bis (2-naphthyl) anthracene (abbreviation: t-BuDNA), 9' -bianthracene (abbreviation: BANT), 9 '- (stilbene-3, 3' -diyl) phenanthrene (abbreviation: DPNS), 9 '- (stilbene-4, 4' -diyl) phenanthrene (abbreviation: DPNS2), 1,3, 5-tris (1-pyrene) benzene (abbreviation: TPB3), 5, 12-diphenyltetracene, 5, 12-bis (biphenyl-2-yl) tetracene, and the like.

When the light-emitting substance is a phosphorescent material, an organic compound having triplet excitation energy larger than that of the light-emitting substance may be selected as an organic compound (host material) to be used in combination with the light-emitting substance. In particular, it is preferable to select an organic compound according to one embodiment of the present invention shown in embodiment 1. Note that when a plurality of organic compounds (for example, a first host material, a second host material (or an auxiliary material), or the like) and a light-emitting substance are used in combination to form an exciplex, it is preferable to use the plurality of organic compounds in a mixture with a phosphorescent material.

By adopting such a structure, it is possible to efficiently obtain light emission of EXTET (excimer-Triplet Energy Transfer) utilizing Energy Transfer from the Exciplex to the light-emitting substance. As the combination of a plurality of organic compounds, a combination in which an exciplex is easily formed is preferably used, and a combination of a compound which easily receives holes (a hole-transporting material) and a compound which easily receives electrons (an electron-transporting material) is particularly preferable. Note that since the organic compound according to one embodiment of the present invention described in embodiment 1 has a stable triplet excited state, it is suitably used as a host material when a light-emitting substance is a phosphorescent material. When the exciplex is formed as described above, the organic compound is suitably used as an electron transporting material. Since it is a triplet excitation level, it is particularly suitable for use in combination with a phosphorescent material which emits green light.

Examples of the organic compound (host material and auxiliary material) which can be used in combination with the light-emitting substance when the light-emitting substance is a phosphorescent material include aromatic amines, carbazole derivatives, dibenzothiophene derivatives, dibenzofuran derivatives, zinc-based metal complexes or aluminum-based metal complexes, oxadiazole derivatives, triazole derivatives, benzimidazole derivatives, quinoxaline derivatives, dibenzoquinoxaline derivatives, pyrimidine derivatives, triazine derivatives, pyridine derivatives, bipyridine derivatives, phenanthroline derivatives, and the like.

Further, as specific examples of the aromatic amine (compound having an aromatic amine skeleton) of the organic compound having a high hole-transporting property, the same materials as those of the specific examples of the hole-transporting material can be given.

Further, as specific examples of the carbazole derivative of the organic compound having a high hole-transporting property, the same materials as those of the specific examples of the hole-transporting material can be given.

Specific examples of dibenzothiophene derivatives and dibenzofuran derivatives of organic compounds having high hole-transporting properties include 4- {3- [3- (9-phenyl-9H-fluoren-9-yl) phenyl ] phenyl } dibenzofuran (mmDBFFLBi-II), 4' - (benzene-1, 3, 5-triyl) tris (dibenzofuran) (DBF 3P-II), 1,3, 5-tris (dibenzothiophen-4-yl) benzene (DBT 3P-II), 2, 8-diphenyl-4- [4- (9-phenyl-9H-fluoren-9-yl) phenyl ] dibenzothiophene (DBTFLP-III), and 4- [4- (9-phenyl-9H-fluoren-9-yl) phenyl ] -6-phenyldibenzothiophene (abbreviated as DBTFLP-IV), 4- [3- (triphenylen-2-yl) phenyl ] dibenzothiophene (abbreviated as mDBTPTp-II), and the like.

Specific examples of the zinc-based metal complex and the aluminum-based metal complex of the organic compound having a high electron-transporting property include: tris (8-quinolinolato) aluminum (III) (Alq for short), tris (4-methyl-8-quinolinolato) aluminum (III) (Almq for short)₃) Bis (10-hydroxybenzo [ h ]]Quinoline) beryllium (II) (abbreviation: BeBq₂) Bis (2-methyl-8-quinolinol) (4-phenylphenol) aluminum (III) (abbreviation: BAlq), bis (8-hydroxyquinoline) zinc (II) (abbreviation: znq) and the like having a quinoline skeleton or a benzoquinoline skeleton.

In addition, metal complexes having an oxazole-based ligand or a thiazole-based ligand, such as bis [2- (2-benzoxazolyl) phenol ] zinc (II) (abbreviated as ZnPBO) and bis [2- (2-benzothiazolyl) phenol ] zinc (II) (abbreviated as ZnBTZ), can be used.

Specific examples of the oxadiazole derivative, triazole derivative, benzimidazole derivative, quinoxaline derivative, dibenzoquinoxaline derivative, and phenanthroline derivative which are organic compounds having high electron transport properties include 2- (4-biphenyl) -5- (4-tert-butylphenyl) -1,3, 4-oxadiazole (abbreviated as PBD), 1, 3-bis [5- (p-tert-butylphenyl) -1,3, 4-oxadiazol-2-yl ] benzene (abbreviated as OXD-7), 9- [4- (5-phenyl-1, 3, 4-oxadiazol-2-yl) phenyl ] -9H-carbazole (abbreviated as CO11), 3- (4-biphenyl) -4-phenyl-5- (4-tert-butylphenyl) -1,2, 4-triazole (abbreviated as TAZ), 2 '- (1,3, 5-benzenetriyl) tris (1-phenyl-1H-benzimidazole) (abbreviated as TPBI), 2- [3- (dibenzothiophen-4-yl) phenyl ] -1-phenyl-1H-benzimidazole (abbreviated as mDBTBIm-II), 4' -bis (5-methylbenzoxazol-2-yl) stilbene (abbreviated as BzOs), bathophenanthroline (abbreviated as Bphen), bathocuproin (abbreviated as BCP), 2, 9-bis (naphthalen-2-yl) -4, 7-diphenyl-1, 10-phenanthroline (abbreviated as NBphen), 2- [3- (dibenzothiophen-4-yl) phenyl ] dibenzo [ f ], h ] quinoxaline (abbreviation: 2mDBTPDBq-II), 2- [3 '- (dibenzothiophen-4-yl) biphenyl-3-yl ] dibenzo [ f, H ] quinoxaline (abbreviation: 2mDBTBPDBq-II), 2- [ 3' - (9H-carbazol-9-yl) biphenyl-3-yl ] dibenzo [ f, H ] quinoxaline (abbreviation: 2mCZBPDBq), 2- [4- (3, 6-diphenyl-9H-carbazol-9-yl) phenyl ] dibenzo [ f, H ] quinoxaline (abbreviation: 2CZPDBq-III), 7- [3- (dibenzothiophen-4-yl) phenyl ] dibenzo [ f, H ] quinoxaline (abbreviation: 7mDBTPDBq-II) and 6- [3- (dibenzothiophen-4-yl) phenyl ] dibenzo [ f, h ] quinoxaline (abbreviated as 6mDBTPDBq-II), and the like.

Specific examples of the heterocyclic compound having a diazine skeleton, the heterocyclic compound having a triazine skeleton, and the heterocyclic compound having a pyridine skeleton, which are organic compounds having a high electron-transporting property, include 4, 6-bis [3- (phenanthren-9-yl) phenyl ] pyrimidine (abbreviated as 4,6mPnP2Pm), 4, 6-bis [3- (4-dibenzothienyl) phenyl ] pyrimidine (abbreviated as 4,6mDBTP2Pm-II), 4, 6-bis [3- (9H-carbazol-9-yl) phenyl ] pyrimidine (abbreviated as 4,6mCzP2Pm), 2- {4- [3- (N-phenyl-9H-carbazol-3-yl) -9H-carbazol-9-yl ] phenyl } -4, 6-diphenyl-1, 3, 5-triazine (abbreviated as PCCzPTzn), 9- [3- (4, 6-diphenyl-1, 3, 5-triazin-2-yl) phenyl ] -9 '-phenyl-2, 3' -bi-9H-carbazole (abbreviated as mPCzPTzn-02), 3, 5-bis [3- (9H-carbazol-9-yl) phenyl ] pyridine (abbreviated as 35DCzPPy), 1,3, 5-tris [3- (3-pyridyl) phenyl ] benzene (abbreviated as TmPyPB), and the like. In particular, the organic compound according to one embodiment of the present invention described in embodiment 1 can be used.

Further, as the organic compound having a high electron-transporting property, a polymer compound such as poly (2, 5-pyridyldiyl) (abbreviated as PPy), poly [ (9, 9-dihexylfluorene-2, 7-diyl) -co- (pyridine-3, 5-diyl) ] (abbreviated as PF-Py), poly [ (9, 9-dioctylfluorene-2, 7-diyl) -co- (2,2 '-bipyridine-6, 6' -diyl) ] (abbreviated as PF-BPy) can be used.

In addition, when a plurality of organic compounds are used for the light-emitting layers (113, 113a, 113b, and 113c), two types of compounds (a first compound and a second compound) that form an exciplex and an organometallic complex may be combined. In this case, various organic compounds can be appropriately combined, but in order to efficiently form an exciplex, it is particularly preferable to combine a compound which easily receives holes (a hole-transporting material) and a compound which easily receives electrons (an electron-transporting material). As specific examples of the hole-transporting material and the electron-transporting material, materials described in this embodiment can be used. By adopting the structure, high efficiency, low voltage and long service life can be realized simultaneously.

The TADF material is a material capable of converting (up-converting) a triplet excited state into a singlet excited state (reverse intersystem crossing) by a small amount of thermal energy and efficiently emitting luminescence (fluorescence) from the singlet excited state. The conditions under which the thermally activated delayed fluorescence can be obtained with high efficiency are as follows: the energy difference between the triplet excitation level and the singlet excitation level is 0eV or more and 0.2eV or less, and preferably 0eV or more and 0.1eV or less. The delayed fluorescence emitted from the TADF material means luminescence having the same spectrum as that of general fluorescence but having a very long lifetime. Having a life of 10^-6Second or more, preferably 10^-3For more than a second.

Examples of the TADF material include fullerene or a derivative thereof, an acridine derivative such as luteolin, and eosin. Further, metal-containing porphyrins containing magnesium (Mg), zinc (Zn), cadmium (Cd), tin (Sn), platinum (Pt), indium (In), palladium (Pd), or the like can be cited. Examples of the metal-containing porphyrin include protoporphyrin-tin fluoride complex (abbreviated as SnF)₂(Proto IX)), mesoporphyrin-tin fluoride complex (abbreviation: SnF₂(Meso IX)), hematoporphyrin-tin fluoride complex (abbreviation: SnF₂(Hemato IX)), coproporphyrin tetramethyl ester-tin fluoride complex (abbreviation: SnF₂(Copro III-4Me)), octaethyl esterPorphyrin-tin fluoride complex (SnF for short)₂(OEP)), protoporphyrin-tin fluoride complex (abbreviation: SnF₂(Etio I)) and octaethylporphyrin-platinum chloride complex (abbreviation: PtCl₂OEP), and the like.

In addition to the above, 2- (biphenyl-4-yl) -4, 6-bis (12-phenylindolo [2, 3-a ] carbazol-11-yl) -1,3, 5-triazine (abbreviation: PIC-TRZ), 2- {4- [3- (N-phenyl-9H-carbazol-3-yl) -9H-carbazol-9-yl ] phenyl } -4, 6-diphenyl-1, 3, 5-triazine (abbreviation: PCCzPTzn), 2- [4- (10H-phenoxazin-10-yl) phenyl ] -4, 6-diphenyl-1, 3, 5-triazine (abbreviation: PXZ-TRZ), 3- [4- (5-phenyl-5, 10-dihydrophenazin-10-yl) phenyl ] -4, 5-diphenyl-1, 2, 4-triazole (abbreviation: PPZ-3TPT), 3- (9, 9-dimethyl-9H-acridin-10-yl) -9H-xanthen-9-one (abbreviation: ACRXTN), bis [4- (9, 9-dimethyl-9, 10-dihydroacridine) phenyl ] sulfone (abbreviation: DMAC-DPS), 10-phenyl-10H, 10 ' H-spiro [ acridine-9, 9 ' -anthracene ] -10 ' -one (abbreviation: ACRSA), etc., having a pi-electron rich heteroaromatic ring and a pi-electron deficient heteroaromatic ring. In addition, in the case where a pi-electron-rich heteroaromatic ring and a pi-electron-deficient heteroaromatic ring are directly bonded to each other, both donor and acceptor of the pi-electron-rich heteroaromatic ring are strong, and the energy difference between a singlet excited state and a triplet excited state is small, which is particularly preferable.

In addition, in the case of using a TADF material, it may be combined with other organic compounds. Particularly, the TADF material may be combined with the above-described host material, hole transporting material, and electron transporting material, and the organic compound according to one embodiment of the present invention described in embodiment 1 is preferably used as the host material combined with the TADF material.

The light-emitting layers (113, 113a, 113b) can be formed using the above materials in combination with a low-molecular material or a high-molecular material. For the film formation, a known method (vapor deposition method, coating method, printing method, or the like) can be suitably used.

In the light-emitting devices shown in fig. 1A to 1E, electron-transporting layers (114, 114a) are formed on the light-emitting layers (113, 113a) of the EL layers (103, 103 a). In the case of the light-emitting device having the series structure shown in fig. 1D, after the EL layer 103a and the charge generation layer 104 are formed, an electron transport layer 114b is further formed over the light-emitting layer 113b of the EL layer 103 b.

< Electron transport layer >

The electron transport layer (114, 114a, 114b) is a layer that transports electrons injected from the second electrode 102 by the electron injection layer (115, 115a, 115b) into the light emitting layer (113, 113a, 113 b). The electron transport layers (114, 114a, 114b) are layers containing an electron-transporting material. The electron-transporting material used for the electron-transporting layers (114, 114a, 114b) is preferably one having an electric field strength [ V/cm ]]Has a square root of 1 × 10 when it is 600^-6cm²A substance having an electron mobility of greater than/Vs. In addition, any substance other than the above may be used as long as it has a higher electron-transport property than a hole-transport property. Further, the organic compound according to one embodiment of the present invention described in embodiment 1 has excellent electron-transporting properties and can be used for an electron-transporting layer.

As the electron transporting material, a metal complex having a quinoline skeleton, a metal complex having a benzoquinoline skeleton, a metal complex having an oxazole skeleton, a metal complex having a thiazole skeleton, or the like can be used, and a material having high electron transporting properties such as an oxadiazole derivative, a triazole derivative, an imidazole derivative, an oxazole derivative, a thiazole derivative, a phenanthroline derivative, a quinoline derivative having a quinoline ligand, a benzoquinoline derivative, a quinoxaline derivative, a dibenzoquinoxaline derivative, a pyridine derivative, a bipyridine derivative, a pyrimidine derivative, a nitrogen-containing heteroaromatic compound, or the like which lacks pi-electron type heteroaromatic compound can be used.

Specific examples of the electron-transporting material include: tris (8-hydroxyquinoline) aluminum (III) (Alq for short)₃) Tris (4-methyl-8-quinolinolato) aluminum (abbreviation: almq₃) Bis (10-hydroxybenzo [ h ]]Quinoline) beryllium (abbreviation: BeBq₂) Bis (2-methyl-8-quinolinol) (4-phenylphenol) aluminum (III) (abbreviation: BAlq), bis (8-hydroxyquinoline) zinc (II) (abbreviation: znq) and the like having a quinoline skeleton or a benzoquinoline skeleton; bis [2- (2-benzoxazolyl) phenol]Zinc (II) (ZnPBO for short), bis (2)2- (2-benzothiazolyl) phenol]And metal complexes having an oxazole skeleton or a thiazole skeleton such as zinc (II) (abbreviated as ZnBTZ).

Furthermore, in addition to the metal complex, oxadiazole derivatives such as 2- (4-biphenyl) -5- (4-tert-butylphenyl) -1,3, 4-oxadiazole (abbreviated as PBD), 1, 3-bis [5- (p-tert-butylphenyl) -1,3, 4-oxadiazol-2-yl ] benzene (abbreviated as OXD-7), 9- [4- (5-phenyl-1, 3, 4-oxadiazol-2-yl) phenyl ] -9H-carbazole (abbreviated as CO11) and the like can be used; triazole derivatives such as 3- (4 '-tert-butylphenyl) -4-phenyl-5- (4' -biphenyl) -1,2, 4-triazole (abbreviated as TAZ) and 3- (4-tert-butylphenyl) -4- (4-ethylphenyl) -5- (4-biphenyl) -1,2, 4-triazole (abbreviated as p-EtTAZ); imidazole derivatives (including benzimidazole derivatives) such as 2, 2' - (1,3, 5-benzenetriyl) tris (1-phenyl-1H-benzimidazole) (abbreviated as TPBI), 2- [3- (dibenzothiophen-4-yl) phenyl ] -1-phenyl-1H-benzimidazole (abbreviated as mDBTBIm-II), and the like; oxazole derivatives such as 4, 4' -bis (5-methylbenzoxazol-2-yl) stilbene (abbreviated as BzOs); phenanthroline derivatives such as bathophenanthroline (abbreviated as BPhen), bathocuproine (abbreviated as BCP), 2, 9-bis (naphthalene-2-yl) -4, 7-diphenyl-1, 10-phenanthroline (abbreviated as NBPhen); 2- [3- (dibenzothiophen-4-yl) phenyl ] dibenzo [ f, H ] quinoxaline (abbreviated as 2mDBTPDBq-II), 2- [3 '- (dibenzothiophen-4-yl) biphenyl-3-yl ] dibenzo [ f, H ] quinoxaline (abbreviated as 2mDBTBPDBq-II), 2- [ 3' - (9H-carbazol-9-yl) biphenyl-3-yl ] dibenzo [ f, H ] quinoxaline (abbreviated as 2mCZBPDBq), 2- [4- (3, 6-diphenyl-9H-carbazol-9-yl) phenyl ] dibenzo [ f, H ] quinoxaline (abbreviated as 2CZPDBq-III), 7- [3- (dibenzothiophen-4-yl) phenyl ] dibenzo [ f, h ] quinoxaline (abbreviated as 7mDBTPDBq-II), quinoxaline derivatives such as 6- [3- (dibenzothiophen-4-yl) phenyl ] dibenzo [ f, H ] quinoxaline (abbreviated as 6mDBTPDBq-II) or dibenzoquinoxaline derivatives, pyridine derivatives such as 3, 5-bis [3- (9H-carbazol-9-yl) phenyl ] pyridine (abbreviated as 35DCzPPy) and 1,3, 5-tris [3- (3-pyridyl) phenyl ] benzene (abbreviated as TmPyPB), pyridine derivatives such as 4, 6-bis [3- (phenanthrene-9-yl) phenyl ] pyrimidine (abbreviated as 4,6 mPp 2Pm), 4, 6-bis [3- (4-dibenzothiophenyl) phenyl ] pyrimidine (abbreviated as 4,6mDBTP2Pm-II) and 4, 6-bis [3- (9H-carbazol-9-yl) phenyl ] pyrimidine (abbreviated as 4,6mCzP2Pm), and the like; triazine derivatives such as 2- {4- [3- (N-phenyl-9H-carbazol-3-yl) -9H-carbazol-9-yl ] phenyl } -4, 6-diphenyl-1, 3, 5-triazine (abbreviated as PCCzPTzn). In particular, the organic compound according to one embodiment of the present invention described in embodiment 1 can be used.

In addition, polymer compounds such as poly (2, 5-pyridyldiyl) (abbreviated as PPy), poly [ (9, 9-dihexylfluorene-2, 7-diyl) -co- (pyridine-3, 5-diyl) ] (abbreviated as PF-Py), poly [ (9, 9-dioctylfluorene-2, 7-diyl) -co- (2,2 '-bipyridine-6, 6' -diyl) ] (abbreviated as PF-BPy) can also be used.

The electron transport layers (114, 114a, 114b) may be a single layer or a stack of two or more layers containing the above substances.

Next, in the light-emitting device shown in fig. 1D, an electron injection layer 115a is formed on the electron transit layer 114a in the EL layer 103a by a vacuum evaporation method. Then, the EL layer 103a and the charge generation layer 104 are formed, and the electron transit layer 114b in the EL layer 103b is formed, and then the electron injection layer 115b is formed thereon by a vacuum evaporation method.

< Electron injection layer >

The electron injection layers (115, 115a, 115b) are layers containing a substance having a high electron injection property. As the electron injection layers (115, 115a, 115b), lithium fluoride (LiF), cesium fluoride (CsF), calcium fluoride (CaF) can be used₂) And lithium oxide (LiO)_x) And the like, alkali metals, alkaline earth metals, or compounds of these metals. In addition, erbium fluoride (ErF) may be used₃) And the like. In addition, an electron salt may be used for the electron injection layer (115, 115a, 115 b). Examples of the electron salt include a mixed oxide of calcium and aluminum to which electrons are added at a high concentration. Further, the electron transport layers (114, 114a, 114b) described above may be used.

Further, a composite material in which an organic compound and an electron donor (donor) are mixed may be used for the electron injection layers (115, 115a, 115 b). This composite material has excellent electron injection and electron transport properties because electrons are generated in an organic compound by an electron donor. In this case, the organic compound is preferably a material excellent in transporting generated electrons, and specifically, for example, an electron transporting material (metal complex, heteroaromatic compound, or the like) used for the electron transporting layers (114, 114a, 114b) as described above can be used. The electron donor may be any one that can supply electrons to the organic compound. Specifically, alkali metals, alkaline earth metals, and rare earth metals are preferably used, and examples thereof include lithium, cesium, magnesium, calcium, erbium, and ytterbium. In addition, alkali metal oxides or alkaline earth metal oxides are preferably used, and examples thereof include lithium oxide, calcium oxide, barium oxide, and the like. In addition, lewis bases such as magnesium oxide can also be used. Further, an organic compound such as tetrathiafulvalene (TTF) may be used.

For example, in the light-emitting device shown in fig. 1D, in the case of amplifying light obtained from the light-emitting layer 113b, it is preferable to form the second electrode 102 so that the optical distance from the light-emitting layer 113b is less than λ/4(λ is the wavelength of light appearing in the light-emitting layer 113 b). In this case, by changing the thickness of the electron transport layer 114b or the electron injection layer 115b, the optical distance can be adjusted.

< Charge generation layer >

In the light-emitting device shown in fig. 1D, the charge generation layer 104 has the following functions: when a voltage is applied between the first electrode 101 (anode) and the second electrode 102 (cathode), electrons are injected into the EL layer 103a and holes are injected into the EL layer 103 b. The charge generation layer 104 may have a structure in which an electron acceptor (acceptor) is added to a hole-transporting material, or may have a structure in which an electron donor (donor) is added to an electron-transporting material. Alternatively, these two structures may be stacked. Further, by forming the charge generation layer 104 using the above materials, increase in driving voltage when the EL layers are stacked can be suppressed.

When the charge generation layer 104 has a structure in which an electron acceptor is added to a hole-transporting material, the materials described in this embodiment mode can be used as the hole-transporting material. Further, as the electron acceptor, 7, 8, 8-tetracyano-2, 3,5, 6-tetrafluoroquinodimethane (abbreviated as F)₄-TCNQ), chloranil, and the like. In addition, theOxides of metals belonging to groups 4 to 8 of the periodic table of the elements can be cited. Specific examples thereof include vanadium oxide, niobium oxide, tantalum oxide, chromium oxide, molybdenum oxide, tungsten oxide, manganese oxide, and rhenium oxide.

In the case where the charge generation layer 104 has a structure in which an electron donor is added to an electron transporting material, the materials described in this embodiment mode can be used as the electron transporting material. In addition, as the electron donor, alkali metal, alkaline earth metal, rare earth metal, or metal belonging to group 2 or group 13 of the periodic table of the elements, and oxide or carbonate thereof can be used. Specifically, lithium (Li), cesium (Cs), magnesium (Mg), calcium (Ca), ytterbium (Yb), indium (In), lithium oxide, cesium carbonate, and the like are preferably used. Further, an organic compound such as tetrathianaphtalene (tetrathianaphtalene) may also be used as the electron donor.

The EL layer 103c in fig. 1E may have the same structure as the EL layers (103, 103a, 103b) described above. The

charge generation layers

104a and 104b may have the same structure as the charge generation layer 104.

< substrate >

The light-emitting device shown in this embodiment mode can be formed over various substrates. Note that there is no particular limitation on the kind of the substrate. Examples of the substrate include a semiconductor substrate (e.g., a single crystal substrate or a silicon substrate), an SOI substrate, a glass substrate, a quartz substrate, a plastic substrate, a metal substrate, a stainless steel substrate, a substrate including a stainless steel foil, a tungsten substrate, a substrate including a tungsten foil, a flexible substrate, a bonding film, a paper film including a fibrous material, a base film, and the like.

Examples of the glass substrate include barium borosilicate glass, aluminoborosilicate glass, and soda lime glass. Examples of the flexible substrate, the adhesive film, and the base film include plastics typified by polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polyether sulfone (PES), synthetic resins such as acrylic resins, polypropylene, polyester, polyvinyl fluoride, polyvinyl chloride, polyamide, polyimide, aramid resins, epoxy resins, inorganic vapor-deposited films, and paper.

In addition, when the light-emitting device described in this embodiment mode is manufactured, a vacuum process such as a vapor deposition method or a solution process such as a spin coating method or an ink jet method can be used. As the vapor deposition method, a physical vapor deposition method (PVD method) such as a sputtering method, an ion plating method, an ion beam vapor deposition method, a molecular beam vapor deposition method, or a vacuum vapor deposition method, a chemical vapor deposition method (CVD method), or the like can be used. In particular, the functional layer (the hole injection layer (111, 111a, 111b), the hole transport layer (112, 112a, 112b), the light emitting layer (113, 113a, 113b, 113c), the electron transport layer (114, 114a, 114b), the electron injection layer (115, 115a, 115b), and the charge generation layer (104, 104a, 104b)) included in the EL layer of the light emitting device can be formed by a method such as a vapor deposition method (vacuum vapor deposition method), a coating method (dip coating method, dye coating method, bar coating method, spin coating method, spray coating method), a printing method (an ink jet method, screen printing (stencil printing) method, offset printing (lithography printing) method, flexography (relief printing) method, gravure printing method, microcontact printing method, nanoimprint method), or the like.

The materials of the functional layers (the hole injection layers (111, 111a, 111b), the hole transport layers (112, 112a, 112b), the light emitting layers (113, 113a, 113b, 113c), the electron transport layers (114, 114a, 114b), the electron injection layers (115, 115a, 115b)) and the charge generation layers (104, 104a, 104b)) constituting the EL layers (103, 103a, 103b) of the light emitting device shown in this embodiment mode are not limited to the above materials, and any materials may be used in combination as long as they satisfy the functions of the respective layers. As an example, a high molecular compound (oligomer, dendrimer, polymer, etc.), a medium molecular compound (compound between low and high molecules: molecular weight 400 to 4000), an inorganic compound (quantum dot material, etc.), or the like can be used. As the quantum dot material, a colloidal quantum dot material, an alloy type quantum dot material, a Core Shell (Core Shell) type quantum dot material, a Core type quantum dot material, or the like can be used.

The structure described in this embodiment can be used in combination with the structures described in the other embodiments as appropriate.

Embodiment 3

In this embodiment, a light-emitting device according to one embodiment of the present invention will be described. The light-emitting device shown in fig. 2A is an active matrix light-emitting device in which a transistor (FET)202 and light-emitting devices (203R, 203G, 203B, and 203W) formed over a first substrate 201 are electrically connected, and a plurality of light-emitting devices (203R, 203G, 203B, and 203W) share an EL layer 204 and have a microcavity structure in which optical distances between electrodes of the light-emitting devices are adjusted according to emission colors of the light-emitting devices. In addition, a top emission type light-emitting device is used in which light obtained from the EL layer 204 is emitted through color filters (206R, 206G, 206B) formed on the second substrate 205.

In the light-emitting device shown in fig. 2A, the first electrode 207 is used as a reflective electrode, and the second electrode 208 is used as a semi-transmissive-semi-reflective electrode. As an electrode material for forming the first electrode 207 and the second electrode 208, any electrode material can be used as appropriate with reference to other embodiments.

In addition, in fig. 2A, for example, in the case where the light emitting device 203R, the light emitting device 203G, the light emitting device 203B, and the light emitting device 203W are respectively a red light emitting device, a green light emitting device, a blue light emitting device, and a white light emitting device, as illustrated in fig. 2B, the distance between the first electrode 207 and the second electrode 208 in the light emitting device 203R is adjusted to the optical distance 200R, the distance between the first electrode 207 and the second electrode 208 in the light emitting device 203G is adjusted to the optical distance 200G, and the distance between the first electrode 207 and the second electrode 208 in the light emitting device 203B is adjusted to the optical distance 200B. In addition, as shown in fig. 2B, optical adjustment can be performed by laminating the conductive layer 210R on the first electrode 207 of the light emitting device 203R and the conductive layer 210G on the first electrode 207 of the light emitting device 203G.

Color filters (206R, 206G, 206B) are formed over the second substrate 205. The color filter transmits visible light of a specific wavelength range and blocks visible light of the specific wavelength range. Therefore, as shown in fig. 2A, by providing a color filter 206R that transmits only light in the red wavelength range at a position overlapping with the light-emitting device 203R, red light can be obtained from the light-emitting device 203R. Further, by providing the color filter 206G which transmits only light in the green wavelength range at a position overlapping with the light emitting device 203G, green light can be obtained from the light emitting device 203G. Further, by providing the color filter 206B which transmits only light in the blue wavelength range at a position overlapping with the light-emitting device 203B, blue light can be obtained from the light-emitting device 203B. However, white light can be obtained from the light-emitting device 203W without providing a color filter. Further, a black layer (black matrix) 209 may be provided at an end portion of each color filter. The color filters (206R, 206G, 206B) or the black layer 209 may be covered with a protective layer made of a transparent material.

Although the light-emitting device of the structure (top emission type) in which light is extracted on the second substrate 205 side is shown in fig. 2A, a light-emitting device of the structure (bottom emission type) in which light is extracted on the first substrate 201 side where the FET202 is formed as shown in fig. 2C may be employed. In the bottom emission type light emitting device, the first electrode 207 is used as a semi-transmissive-semi-reflective electrode, and the second electrode 208 is used as a reflective electrode. As the first substrate 201, at least a substrate having a light-transmitting property is used. As shown in fig. 2C, the color filters (206R ', 206G ', 206B ') may be provided on the side closer to the first substrate 201 than the light-emitting devices (203R, 203G, 203B).

In addition, although fig. 2A illustrates a case where the light-emitting device is a red light-emitting device, a green light-emitting device, a blue light-emitting device, or a white light-emitting device, the light-emitting device according to one embodiment of the present invention is not limited to this configuration, and a yellow light-emitting device or an orange light-emitting device may be used. As a material for manufacturing an EL layer (a light-emitting layer, a hole injection layer, a hole transport layer, an electron injection layer, a charge generation layer, or the like) of these light-emitting devices, it can be used as appropriate with reference to other embodiments. In this case, the color filter needs to be appropriately selected according to the emission color of the light emitting device.

By adopting the above configuration, a light-emitting device including a light-emitting device that emits light of a plurality of colors can be obtained.

Embodiment 4

In this embodiment, a light-emitting device which is one embodiment of the present invention will be described.

By adopting the element structure of the light-emitting device according to one embodiment of the present invention, an active matrix light-emitting device or a passive matrix light-emitting device can be manufactured. In addition, the active matrix light-emitting device has a structure in which a light-emitting device and a transistor (FET) are combined. Thus, both the passive matrix light-emitting device and the active matrix light-emitting device are included in one embodiment of the present invention. Further, the light-emitting device shown in other embodiments can be applied to the light-emitting apparatus shown in this embodiment.

In this embodiment, an active matrix light-emitting device will be described with reference to fig. 3A and 3B.

Fig. 3A is a plan view of the light emitting device, and fig. 3B is a sectional view cut along a chain line a-a' in fig. 3A. An active matrix light-emitting device includes a pixel portion 302, a driver circuit portion (source line driver circuit) 303, and a driver circuit portion (gate line driver circuit) (304a and 304b) provided over a first substrate 301. The pixel portion 302 and the driver circuit portions (303, 304a, 304b) are sealed between the first substrate 301 and the second substrate 306 with a sealant 305.

A lead 307 is provided over the first substrate 301. The lead wire 307 is electrically connected to an FPC308 as an external input terminal. The FPC308 is used to transmit signals (for example, video signals, clock signals, start signals, reset signals, or the like) or potentials from the outside to the driver circuit portions (303, 304a, 304 b). In addition, the FPC308 may be mounted with a Printed Wiring Board (PWB). The state in which these FPC and PWB are mounted may be included in the category of the light-emitting device.

Fig. 3B shows a cross-sectional structure.

The pixel portion 302 is configured by a plurality of pixels each having an FET (switching FET)311, an FET (current control FET)312, and a first electrode 313 electrically connected to the FET 312. The number of FETs provided in each pixel is not particularly limited, and may be appropriately set as necessary.

The

FETs

309, 310, 311, and 312 are not particularly limited, and for example, staggered transistors, inverted staggered transistors, or the like can be used. Further, a transistor structure of a top gate type, a bottom gate type, or the like may be employed.

Further, the crystallinity of a semiconductor which can be used for the

FETs

309, 310, 311, and 312 is not particularly limited, and any of an amorphous semiconductor and a semiconductor having crystallinity (a microcrystalline semiconductor, a polycrystalline semiconductor, a single crystal semiconductor, or a semiconductor a part of which has a crystalline region) can be used. The use of a semiconductor having crystallinity is preferable because deterioration of transistor characteristics can be suppressed.

As the semiconductor, for example, a group 14 element, a compound semiconductor, an oxide semiconductor, an organic semiconductor, or the like can be used. Typically, a semiconductor containing silicon, a semiconductor containing gallium arsenide, an oxide semiconductor containing indium, or the like can be used.

The driver circuit portion 303 includes

FETs

309 and 310. The driver circuit portion 303 may be formed of a circuit including a transistor having a single polarity (either of N-type and P-type), or may be formed of a CMOS circuit including an N-type transistor and a P-type transistor. Further, a configuration having a driving circuit outside may be employed.

The end of the first electrode 313 is covered with an insulator 314. As the insulator 314, an organic compound such as a negative photosensitive resin or a positive photosensitive resin (acrylic resin) or an inorganic compound such as silicon oxide, silicon oxynitride, or silicon nitride can be used. The upper or lower end of the insulator 314 preferably has a surface with curvature. This makes it possible to provide a film formed on the insulator 314 with good coverage.

An EL layer 315 and a second electrode 316 are stacked over the first electrode 313. The EL layer 315 includes a light-emitting layer, a hole-injecting layer, a hole-transporting layer, an electron-injecting layer, a charge-generating layer, and the like.

As the structure of the light-emitting device 317 described in this embodiment mode, structures or materials described in other embodiment modes can be applied. Although not shown here, the second electrode 316 is electrically connected to the FPC308 serving as an external input terminal.

Although only one light emitting device 317 is illustrated in the cross-sectional view illustrated in fig. 3B, a plurality of light emitting devices are arranged in a matrix in the pixel portion 302. By selectively forming light-emitting devices capable of emitting light of three (R, G, B) colors in the pixel portion 302, a light-emitting device capable of full-color display can be formed. In addition to the light-emitting device capable of obtaining light emission of three colors (R, G, B), for example, a light-emitting device capable of obtaining light emission of colors such as white (W), yellow (Y), magenta (M), and cyan (C) may be formed. For example, by adding a light-emitting device capable of obtaining the above-described plurality of types of light emission to a light-emitting device capable of obtaining light emission of three (R, G, B) colors, effects such as improvement in color purity and reduction in power consumption can be obtained. Further, a light-emitting device capable of full-color display may be realized by combining with a color filter. As the kind of the color filter, red (R), green (G), blue (B), cyan (C), magenta (M), yellow (Y), or the like can be used.

By attaching the second substrate 306 to the first substrate 301 using the sealant 305, the FETs (309, 310, 311, 312) and the light emitting device 317 over the first substrate 301 are located in a region 318 surrounded by the first substrate 301, the second substrate 306, and the sealant 305. In addition, the region 318 may be filled with an inert gas (e.g., nitrogen, argon, etc.) or with an organic substance (including the sealant 305).

Epoxy or glass frit may be used as the sealant 305. As the sealing agent 305, a material which does not transmit moisture or oxygen as much as possible is preferably used. In addition, the same material as that of the first substrate 301 can be used for the second substrate 306. Thus, various substrates shown in other embodiments can be used. As the substrate, a plastic substrate made of FRP (Fiber-Reinforced Plastics), PVF (polyvinyl fluoride), polyester, acrylic resin, or the like can be used in addition to a glass substrate and a quartz substrate. In the case where glass frit is used as a sealant, a glass substrate is preferably used for the first substrate 301 and the second substrate 306 in view of adhesiveness.

As described above, an active matrix light-emitting device can be obtained.

In the case of forming an active matrix light-emitting device over a flexible substrate, the FET and the light-emitting device may be formed directly over the flexible substrate, or the FET and the light-emitting device may be formed over another substrate having a release layer, and then the FET and the light-emitting device may be separated from each other by applying heat, force, laser irradiation, or the like to the release layer and then transferred to the flexible substrate. The release layer may be, for example, a laminate of an inorganic film such as a tungsten film and a silicon oxide film, or an organic resin film such as polyimide. In addition to a substrate in which a transistor can be formed, examples of the flexible substrate include a paper substrate, a cellophane substrate, an aramid film substrate, a polyimide film substrate, a cloth substrate (including natural fibers (silk, cotton, hemp), synthetic fibers (nylon, polyurethane, polyester), regenerated fibers (acetate fibers, cuprammonium fibers, rayon, regenerated polyester), and the like), a leather substrate, a rubber substrate, and the like. By using such a substrate, it is possible to realize excellent resistance and heat resistance, and to reduce the weight and thickness of the substrate.

Embodiment 5

In this embodiment, examples of various electronic devices and automobiles each using the light-emitting device according to one embodiment of the present invention or the light-emitting device including the light-emitting device according to one embodiment of the present invention will be described. Note that the light-emitting device can be mainly used for the display portion in the electronic apparatus described in this embodiment mode.

The electronic apparatus shown in fig. 4A to 4E may include a housing 7000, a display portion 7001, a speaker 7003, an LED lamp 7004, operation keys 7005 (including a power switch or an operation switch), connection terminals 7006, a sensor 7007 (having a function of measuring a force, a displacement, a position, a velocity, an acceleration, an angular velocity, a rotational speed, a distance, light, liquid, magnetism, a temperature, a chemical substance, sound, time, hardness, an electric field, current, voltage, electric power, radiation, a flow rate, humidity, inclination, vibration, odor, or infrared ray), a microphone 7008, and the like.

Fig. 4A shows a mobile computer which may include a switch 7009, an infrared port 7010, and the like, in addition to those described above.

Fig. 4B shows a portable image reproducing apparatus (for example, a DVD reproducing apparatus) provided with a recording medium, which can include the second display portion 7002, the recording medium reading portion 7011, and the like in addition to the above.

Fig. 4C shows a digital camera having a television receiving function, which can include an antenna 7014, a shutter button 7015, an image receiving portion 7016, and the like in addition to the above.

Fig. 4D shows a portable information terminal. The portable information terminal has a function of displaying information on three or more surfaces of the display portion 7001. Here, an example is shown in which the information 7052, the information 7053, and the information 7054 are displayed on different surfaces. For example, in a state where the portable information terminal is placed in a jacket pocket, the user can confirm the information 7053 displayed at a position viewed from above the portable information terminal. The user can confirm the display without taking out the portable information terminal from the pocket and can judge whether to answer the call.

Fig. 4E shows a portable information terminal (including a smartphone), which can include a display portion 7001, operation keys 7005, and the like in a housing 7000. The portable information terminal may be provided with a speaker 9003, a connection terminal 7006, a sensor 9007, and the like. In addition, the portable information terminal can display text or image information on a plurality of surfaces thereof. Here, an example of three icons 7050 is shown. Further, information 7051 indicated by a dotted rectangle may be displayed on the other surface of the display portion 7001. Examples of the information 7051 include information for prompting reception of an email, SNS (Social Networking Services), a telephone, or the like; titles of e-mails or SNS, etc.; a sender name of an email, SNS, or the like; a date; time; the remaining amount of the battery; and antenna received signal strength, etc. Alternatively, an icon 7050 or the like may be displayed at a position where the information 7051 is displayed.

Fig. 4F is a large-sized television device (also referred to as a television or a television receiver), and may include a housing 7000, a display portion 7001, and the like. In addition, the structure of the housing 7000 supported by the stand 7018 is shown here. In addition, the television apparatus can be operated by using a remote controller 7111 or the like which is separately provided. The display portion 7001 may be provided with a touch sensor, and the display portion 7001 may be touched with a finger or the like to be operated. The remote controller 7111 may include a display unit for displaying data output from the remote controller 7111. By using an operation key or a touch panel provided in the remote controller 7111, a channel and a volume can be operated, and an image displayed on the display portion 7001 can be operated.

The electronic devices shown in fig. 4A to 4F may have various functions. For example, the following functions may be provided: a function of displaying various information (still image, moving image, character image, and the like) on the display unit; a touch panel function; a function of displaying a calendar, date, time, or the like; a function of controlling processing by using various software (programs); a wireless communication function; a function of connecting to various computer networks by using a wireless communication function; a function of transmitting or receiving various data by using a wireless communication function; a function of reading out a program or data stored in a recording medium and displaying the program or data on a display unit. Further, an electronic apparatus including a plurality of display portions may have a function of mainly displaying image information on one display portion and mainly displaying text information on another display portion, a function of displaying a three-dimensional image by displaying an image in consideration of parallax on a plurality of display portions, or the like. Further, the electronic device having the image receiving unit may have the following functions: a function of shooting a still image; a function of shooting a moving image; a function of automatically or manually correcting the captured image; a function of storing a captured image in a recording medium (external or built-in camera); a function of displaying the captured image on a display unit, and the like. Note that the functions that the electronic apparatuses shown in fig. 4A to 4F may have are not limited to the above-described functions, but may have various functions.

Fig. 4G is a wristwatch-type portable information terminal that can be used as a smart watch, for example. The wristwatch-type portable information terminal includes a housing 7000, a display portion 7001,

operation buttons

7022, 7023, a connection terminal 7024, a band 7025, a microphone 7026, a sensor 7029, a speaker 7030, and the like. Since the display surface of the display portion 7001 is curved, display can be performed along the curved display surface. Further, the wristwatch-type portable information terminal can perform a handsfree call by communicating with a headset that can perform wireless communication, for example. In addition, data transmission or charging with another information terminal can be performed by using the connection terminal 7024. Charging may also be by wireless power.

The display portion 7001 mounted in the housing 7000 also serving as a frame (bezel) portion has a display region having a non-rectangular shape. The display unit 7001 can display an icon 7027 indicating time, other icons 7028, and the like. The display portion 7001 may be a touch panel (input/output device) to which a touch sensor (input device) is attached.

The smart watch shown in fig. 4G may have various functions. For example, the following functions may be provided: a function of displaying various information (still image, moving image, character image, and the like) on the display unit; a touch panel function; a function of displaying a calendar, date, time, or the like; a function of controlling processing by using various software (programs); a wireless communication function; a function of connecting to various computer networks by using a wireless communication function; a function of transmitting or receiving various data by using a wireless communication function; a function of reading out a program or data stored in a recording medium and displaying the program or data on a display unit.

The interior of the housing 7000 may be provided with a speaker, a sensor (having a function of measuring a force, a displacement, a position, a velocity, an acceleration, an angular velocity, a rotational speed, a distance, light, liquid, magnetism, temperature, a chemical substance, sound, time, hardness, an electric field, current, voltage, electric power, radiation, flow, humidity, inclination, vibration, smell, or infrared ray), a microphone, or the like.

The light-emitting device according to one embodiment of the present invention and the display device including the light-emitting device according to one embodiment of the present invention can be used for each display portion of the electronic device described in this embodiment, whereby an electronic device having a long service life can be realized.

As an electronic device using a light-emitting device, a foldable portable information terminal shown in fig. 5A to 5C can be given. Fig. 5A shows the portable information terminal 9310 in an expanded state. Fig. 5B shows the portable information terminal 9310 in the middle of changing from one state to the other state of the expanded state and the folded state. Fig. 5C shows a portable information terminal 9310 in a folded state. The portable information terminal 9310 has good portability in the folded state and has a large display area seamlessly connected in the unfolded state, so that it has a high display list.

The display portion 9311 is supported by three housings 9315 connected by hinge portions 9313. The display portion 9311 may be a touch panel (input/output device) to which a touch sensor (input device) is attached. Further, the display portion 9311 can be reversibly changed from the folded state to the unfolded state of the portable information terminal 9310 by folding the two housings 9315 with the hinge portions 9313. A light-emitting device according to one embodiment of the present invention can be used for the display portion 9311. In addition, an electronic device having a long service life can be realized. The display region 9312 in the display portion 9311 is a display region located on the side of the portable information terminal 9310 in a folded state. An information icon, a shortcut of an application or program that is frequently used, or the like can be displayed in the display region 9312, and information can be confirmed or the application can be started smoothly.

Fig. 6A and 6B show an automobile using a light-emitting device. That is, the light emitting device may be formed integrally with the automobile. Specifically, the present invention can be applied to a lamp 5101 (including a rear body portion) on the outer side of the automobile shown in fig. 6A, a hub 5102 of a tire, a part or the whole of a door 5103, and the like. The present invention can be applied to a display portion 5104, a steering wheel 5105, a shift lever 5106, a seat 5107, an interior mirror 5108, and the like on the inside of the vehicle shown in fig. 6B. In addition to this, it can also be used for a part of a glazing.

As described above, an electronic device or an automobile using the light-emitting device and the display device according to one embodiment of the present invention can be obtained. At this time, an electronic apparatus having a long service life can be realized. The electronic device or the automobile that can be used is not limited to the electronic device or the automobile shown in this embodiment, and can be applied to various fields.

Note that the structure described in this embodiment can be used in appropriate combination with the structures described in other embodiments.

Embodiment 6

In this embodiment, a structure of an illumination device manufactured by applying a light-emitting device according to one embodiment of the present invention or a part of a light-emitting device thereof will be described with reference to fig. 7A and 7B.

Fig. 7A and 7B show examples of cross-sectional views of the illumination device. Fig. 7A is a bottom emission type lighting device extracting light on the substrate side, and fig. 7B is a top emission type lighting device extracting light on the sealing substrate side.

The lighting apparatus 4000 illustrated in fig. 7A includes a light-emitting device 4002 over a substrate 4001. In addition, the lighting device 4000 includes a substrate 4003 having irregularities on the outer side of the substrate 4001. The light-emitting device 4002 includes a first electrode 4004, an EL layer 4005, and a second electrode 4006.

The first electrode 4004 is electrically connected to the electrode 4007, and the second electrode 4006 is electrically connected to the electrode 4008. In addition, an auxiliary wiring 4009 electrically connected to the first electrode 4004 may be provided. Further, an insulating layer 4010 is formed over the auxiliary wiring 4009.

The substrate 4001 and the sealing substrate 4011 are bonded by a sealant 4012. Further, a drying agent 4013 is preferably provided between the sealing substrate 4011 and the light-emitting device 4002. Since the substrate 4003 has irregularities as shown in fig. 7A, the extraction efficiency of light generated in the light-emitting device 4002 can be improved.

The lighting device 4200 illustrated in fig. 7B includes a light emitting device 4202 on a substrate 4201. The light emitting device 4202 includes a first electrode 4204, an EL layer 4205, and a second electrode 4206.

The first electrode 4204 is electrically connected to the electrode 4207, and the second electrode 4206 is electrically connected to the electrode 4208. In addition, an auxiliary wiring 4209 electrically connected to the second electrode 4206 may be provided. In addition, an insulating layer 4210 may be provided under the auxiliary wiring 4209.

The substrate 4201 and the sealing substrate 4211 having the concave and convex are bonded by a sealant 4212. Further, a barrier film 4213 and a planarization film 4214 may be provided between the sealing substrate 4211 and the light-emitting device 4202. Since the sealing substrate 4211 has irregularities as shown in fig. 7B, the extraction efficiency of light generated in the light emitting device 4202 can be improved.

An example of an application of the lighting device is a ceiling lamp for indoor lighting. As the ceiling spotlight, there are a ceiling-mounted type lamp, a ceiling-embedded type lamp, and the like. Such lighting means may be constituted by a combination of light emitting means and a housing or cover.

In addition, the present invention can be applied to a footlight that can illuminate the ground to improve safety. For example, the footlight can be effectively used in bedrooms, stairs, passageways, and the like. In this case, the size or shape of the room may be appropriately changed according to the size or structure thereof. Further, the light emitting device and the support base may be combined to constitute a mounting type lighting device.

In addition, the present invention can also be applied to a film-like illumination device (sheet illumination). Since the sheet type lighting is used by being attached to a wall, it does not require a space and can be applied to various uses. In addition, a large area can be easily realized. Alternatively, it may be attached to a wall or housing having a curved surface.

By using the light-emitting device according to one embodiment of the present invention or a part of the light-emitting device thereof in a part of indoor furniture other than the above, a lighting device having a function of furniture can be provided.

As described above, various lighting devices using the light-emitting device can be obtained. In addition, such a lighting device is included in one embodiment of the present invention.

Example 1

Synthesis example 1

In this example, a method for synthesizing an organic compound 3- [3- (dibenzothiophen-4-yl) phenyl ] -7-phenyl [1] benzofuro [3,2-c ] pyridazine (abbreviated as 7Ph-3mDBtPBfpd), which is one embodiment of the present invention and is represented by the structural formula (100) in embodiment 1, will be described. The structure of 7Ph-3mDBtPBfpd is shown below.

[ chemical formula 19]

< step 1; synthesis of Ethyl 2- (6-chloro-3-oxo-1-benzofuran-2-yl) -2-acetoxy

First, 24mL of glyoxylic acid ethyl (polymer type) (47% toluene solution) was placed in a three-necked flask, and 230mL of toluene was added after the air in the three-necked flask was replaced with nitrogen. 0.54g (4.7mmol) of trifluoroacetic acid was added to the mixture in an ice bath, and stirring was performed at 0 ℃ for 30 minutes. 30g (178mmol) of 6-chlorobenzofuran-3-one was added thereto, and the mixture was heated to 50 ℃ and stirred for 39 hours. After a predetermined period of time had elapsed, the precipitated solid was suction-filtered and washed with water, ethanol and toluene to obtain 7.2g of a desired white solid. The aqueous layer and the organic layer were separated by adding water to the filtrate obtained here.

The organic layer was washed with saturated brine, and anhydrous magnesium sulfate was added to the organic layer to dry the organic layer, followed by gravity filtration. After the filtrate was concentrated, the solid obtained was washed with toluene to obtain 4.0g of a white solid of the objective compound. The filtrate obtained here was purified by silica gel column chromatography. As developing solvent toluene was used first, in the last ratio being toluene: ethyl acetate ═ 2: the mode 1 increases the amount of ethyl acetate added, thereby increasing the polarity. After the obtained fraction was concentrated, the obtained solid was washed with toluene to obtain 5.4g of a white solid of the objective compound (total 17g, yield 52%). (a-1) shows the synthetic scheme of step 1.

[ chemical formula 20]

< step 2; synthesis of 7-chloro [1] benzofuro [3,2-c ] pyridazin-3-one >

Then, 22g (81mmol) of ethyl 2- (6-chloro-3-oxo-1-benzofuran-2-yl) -2-acetoxyl obtained in the above step 1 and 340mL of ethanol were placed in a three-necked flask, 12g (240mmol) of hydrazine monohydrate was added thereto, and the mixture was stirred at room temperature for one night and then heated under reflux for 40 hours. The resulting reaction mixture was added to water and stirred at room temperature. The mixture was filtered with suction, and the obtained solid was washed with ethanol to obtain 5.5g of a desired product in a yield of 30% as a pale orange solid. (a-2) shows the synthetic scheme of step 2.

[ chemical formula 21]

< step 3; synthesis of 3, 7-dichloro [1] benzofuro [3,2-c ] pyridazine >

Subsequently, 5.5g (25mmol) of 7-chloro [1] benzofuro [3,2-c ] pyridazin-3-one obtained in the above step 2 and 80mL of toluene were placed in a three-necked flask, and 19g (125mmol) of phosphorus oxychloride and 0.1mL of dimethylformamide were added thereto and the mixture was refluxed for 12 hours.

In the reaction mixture obtained in the ice bath, the reaction mixture was gradually added to an aqueous sodium hydroxide solution to perform neutralization. The aqueous and organic layers were separated and the aqueous layer was extracted with toluene. The obtained organic layer was washed with saturated brine, and anhydrous magnesium sulfate was added to the organic layer to dry the organic layer. The resulting mixture was gravity-filtered, and the resulting filtrate was concentrated to obtain a solid. This solid was dissolved in heated toluene, and the mixture was filtered through a filter containing diatomaceous earth, alumina, and diatomaceous earth stacked in this order. The obtained filtrate was concentrated, and the solid was washed with ethanol to obtain 3.7g of the objective compound as a white solid with a yield of 63%. (a-3) shows the synthetic scheme of step 3.

[ chemical formula 22]

< step 4; synthesis of 7-chloro-3- [3- (dibenzothiophen-4-yl) phenyl ] [1] benzofuro [3,2-c ] pyridazine >

Then, 3.1g (13mmol) of 3, 7-dichloro [1] benzofuro [3,2-c ] pyridazine obtained in the above-mentioned step 3, 4.4g (14mmol) of 3- (dibenzothiophen-4-yl) phenylboronic acid, 9.1g (43mmol) of tripotassium phosphate, 0.22g (0.52mmol) of 2-dicyclohexylphosphino-2 ', 6' -dimethoxybiphenyl (S-phos), and 130mL of xylene were put into a reaction vessel, and the inside of the reaction vessel was degassed and the air in the vessel was replaced with nitrogen. 63mg (0.28mmol) of palladium (II) acetate was added to the mixture, and the mixture was stirred with heating at 120 ℃ for 12 hours. 0.22g (0.52mmol) of S-phos and 63mg (0.28mmol) of palladium (II) acetate were added thereto, and the mixture was stirred at 130 ℃ for 8.5 hours under heating. To this solution, 0.95g (3.1mmol) of 3- (dibenzothiophen-4-yl) phenylboronic acid, 2.0g (9.4mmol) of tripotassium phosphate, 0.21g (0.52mmol) of S-phos, and 59mg (0.27mmol) of palladium (II) acetate were further added, and the mixture was stirred at 130 ℃ for 14 hours under heating. To this solution, 0.95g (3.1mmol) of 3- (dibenzothiophen-4-yl) phenylboronic acid, 2.0g (9.4mmol) of tripotassium phosphate, 0.21g (0.52mmol) of S-phos, and 54mg (0.24mmol) of palladium (II) acetate were further added, and the mixture was stirred at 130 ℃ for 7 hours. To this solution, 0.95g (3.1mmol) of 3- (dibenzothiophen-4-yl) phenylboronic acid, 1.9g (9.0mmol) of tripotassium phosphate, 0.23g (0.56mmol) of S-phos, and 71mg (0.32mmol) of palladium (II) acetate were further added, and the mixture was stirred at 130 ℃ for 4 hours. The resulting reaction mixture was filtered with suction, and the solid was washed with water and ethanol. The solid was dissolved in heated toluene, and 90g of alumina was added thereto, followed by heating and stirring at 90 ℃. The mixture was filtered through celite with suction and washed with heated toluene. The resulting filtrate was concentrated to obtain a brown solid. The solid was recombined with toluene to obtain the desired 1.6g of a white solid with a yield of 27%. (a-4) shows the synthetic scheme of step 4.

[ chemical formula 23]

< step 5; synthesis of 3- [3- (dibenzothiophen-4-yl) phenyl ] -7-phenyl [1] benzofuro [3,2-c ] pyridazine (abbreviation: 7Ph-3mDBtPBfpd) >

Next, 0.53g (1.1mmol) of 7-chloro-3- [3- (dibenzothiophen-4-yl) phenyl ] [1] benzofuro [3,2-c ] pyridazine obtained in the above step 4, 0.18g (1.4mmol) of phenylboronic acid, 0.62g (4.1mmol) of cesium fluoride and 30mL of xylene were placed in a reaction vessel, and the atmosphere in the vessel was replaced with nitrogen. After the mixture was heated to 60 ℃ while stirring, 27mg (0.029mmol) of tris (dibenzylideneacetone) dipalladium (0) and 25mg (0.069mmol) of 2' - (dicyclohexylphosphino) acetophenone vinyl ketal were added, and the temperature was raised to 110 ℃ and stirred with heating for 23 hours.

After a predetermined period of time, 25mg (0.029mmol) of tris (dibenzylideneacetone) dipalladium (0) and 26mg (0.069mmol) of 2' - (dicyclohexylphosphino) acetophenone vinyl ketal were added to the mixture, and the mixture was stirred with heating at 120 ℃ for 39 hours.

After a predetermined period of time had elapsed, 0.086g (0.70mmol) of phenylboronic acid, 0.3g (2.0mmol) of cesium fluoride, 12mg (0.013mmol) of tris (dibenzylideneacetone) dipalladium (0) and 13mg (0.036mmol) of 2' - (dicyclohexylphosphino) acetophenone vinyl ketal were added to the mixture, and the mixture was stirred with heating for 13 hours.

The resulting mixture was filtered with suction and the solid was washed with water and ethanol. This solid was dissolved in heated toluene, and the mixture was filtered through a filter containing diatomaceous earth, alumina, and diatomaceous earth stacked in this order. The resulting filtrate was concentrated to give a solid. The solid was recombined with toluene to obtain 0.23g of the objective substance as a white solid with a yield of 40%. The following formula (a-5) shows the synthesis scheme of step 5.

[ chemical formula 24]

The following shows the nuclear magnetic resonance method of the white solid obtained in the above step 5¹H-NMR). In addition, FIG. 8 shows¹H-NMR spectrum. As a result, it was found that in this example, the organic compound of one embodiment of the present invention represented by the structural formula (100) was obtainedThe compound, i.e., 7Ph-3 mDBtPBfpd.

¹H-NMR.δ(CDCl₃):7.44-7.55(m,5H),7.60-7.64(m,2H),7.71-7.76(m,3H),7.80(dd,1H),7.86-7.88(m,2H),7.92(ddd,1H),8.05(s,1H),8.21-8.24(m,2H),8.32(d,1H),8.51(d,1H),8.57(dd,1H).

Property of 7Ph-3mDBtPBfpd

Subsequently, the ultraviolet-visible absorption spectrum (hereinafter, simply referred to as "absorption spectrum") and the emission spectrum in a toluene solution of 7Ph-3mDBtPBfpd were measured. For the measurement of the absorption spectrum in the toluene solution, an ultraviolet-visible spectrophotometer (V550 type, manufactured by japan spectrophotometers) was used. For the measurement of the emission spectrum, a fluorescence spectrophotometer (FS 920 manufactured by hamamatsu photonics corporation, japan) was used. Fig. 9 shows the measurement results of the absorption spectrum and the emission spectrum of the obtained toluene solution. The horizontal axis represents wavelength and the vertical axis represents absorption intensity.

As is clear from the results shown in FIG. 9, the toluene solution of 7Ph-3mDBtPBfpd showed absorption peaks at about 333nm and 281nm, and a luminescence wavelength peak at about 449 nm.

Next, the phosphorescence spectrum of a toluene solution of 7Ph-3mDBtPBfpd was measured. In the measurement of the phosphorescence spectrum, a toluene deoxygenated solution was placed in a quartz cell under a nitrogen atmosphere in a glove box (LABstar M13(1250/780) manufactured by Nippon Kogyo Co., Ltd.) using an absolute PL quantum yield measuring apparatus (C11347-01 manufactured by Nippon Kogyo Co., Ltd.) and was sealed, and the measurement was performed at a liquid nitrogen temperature. Fig. 10 shows the measurement results of the obtained phosphorescence spectrum. The horizontal axis represents wavelength and the vertical axis represents absorption intensity.

From the results shown in FIG. 10, it is understood that a phosphorescence spectrum is observed at 479nm in a toluene solution of 7Ph-3mDBtPBfpd at a liquid nitrogen temperature.

It can be said that the organic compound 7Ph-3mDBtPBfpd according to one embodiment of the present invention has a high T1 level and is suitable as a host material for a phosphorescent material (guest material) which emits light in the vicinity of green. Note that the organic compound 7Ph-3mDBtPBfpd which is one embodiment of the present invention can also be used as a host material or a light-emitting substance of a phosphorescent light-emitting substance in a visible region.

Example 2

Synthesis example 2

In this example, a method for synthesizing an organic compound 7- (1, 1' -biphenyl-3-yl) -3- [3- (dibenzothiophen-4-yl) phenyl ] [1] benzofuro [3,2-c ] pyridazine (abbreviated as 7mBP-3mDBtPBfpd) according to one embodiment of the present invention, which is represented by the structural formula (101) in embodiment 1, will be described. The structures of 7mBP-3mDBtPBfpd are shown below.

[ chemical formula 25]

< step 1; synthesis of 7mBP-3mDBtPBfpd >

1.6g (3.5mmol) of 7-chloro-3- [3- (dibenzothiophen-4-yl) phenyl ] [1] benzofuro [3,2-c ] pyridazine obtained in step 4 of the above-mentioned example 1 (Synthesis example 1), 0.71g (3.5mmol) of 3-biphenylboronic acid, 2.2g (11mmol) of tripotassium phosphate, 35mL of diglyme, and 0.79g (11mmol) of t-butanol were placed in a reaction vessel, and the inside of the vessel was degassed and the atmosphere inside the vessel was replaced with nitrogen.

The mixture was warmed to 60 ℃ and 16mg (0.070mmol) of palladium (II) acetate and 50mg (0.14mmol) of bis (1-adamantane) -n-butylphosphine (cataCXiumA) were added, followed by stirring at 90 ℃ for 6.5 hours. To this solution were added 8mg (0.035mmol) of palladium (II) acetate and 25mg (0.070mmol) of cataCXiumA, and the mixture was stirred at 90 ℃ for 8 hours. To the resulting reaction mixture was added water, and the solid was filtered with suction and washed with ethanol. This solid was dissolved in heated toluene, and the mixture was filtered through a filter containing diatomaceous earth, alumina, and diatomaceous earth stacked in this order.

The resulting filtrate was concentrated to give an oil. The oil was purified by silica gel column chromatography. As developing solvent, toluene was used first, and then toluene: ethyl acetate ═ 9: 1. Ethanol was added to the oily product obtained by concentrating the obtained fraction, and ultrasonic waves were irradiated thereto, whereby a solid precipitated. This solid was filtered with suction to obtain 1.45g of the objective product as a white solid with a yield of 71%. The following formula (b-1) shows the synthesis scheme of step 1.

[ chemical formula 26]

The resulting 1.4g of white solid was purified by sublimation using a gradient sublimation method. The solid was heated under sublimation purification conditions of a pressure of 2.13Pa and a heating temperature of 325 ℃. After sublimation purification, 0.72g of the recovered white solid was purified by sublimation again. Sublimation purification was carried out under a pressure of 2.45Pa and a heating temperature of 310 ℃. After sublimation purification, 7- (1, 1' -biphenyl-3-yl) -3- [3- (dibenzothiophen-4-yl) phenyl ] [1] benzofuro [3,2-c ] pyridazine (abbreviated as: 7mBP-3mDBtPBfpd) was obtained in a yield of 0.57g (white solid, recovery: 79%).

The following shows the nuclear magnetic resonance method of the white solid obtained in the above step 1: (¹H-NMR). In addition, FIG. 11 shows¹H-NMR spectrum. As a result, in this example, 7mBP-3mDBtPBfpd, which is an organic compound according to one embodiment of the present invention represented by the structural formula (101), was obtained.

¹H-NMR.δ(CD₂Cl₂):7.39-7.42(m,1H),7.49-7.54(m,4H),7.60-7.79(m,8H),7.89-7.91(m,2H),7.93(ddd,1H),7.97-7.98(m,2H),8.10(s,1H),8.25-8.27(m,2H),8.31(d,1H),8.52(d,1H),8.60(t,1H).

Properties of 7mBP-3mDBtPBfpd

Next, the ultraviolet-visible absorption spectrum (hereinafter, simply referred to as "absorption spectrum") and the emission spectrum in a toluene solution of 7mBP-3mDBtPBfpd were measured. For the measurement of the absorption spectrum in the toluene solution, an ultraviolet-visible spectrophotometer (V550 type, manufactured by japan spectrophotometers) was used. For measurement of the emission spectrum, a fluorescence spectrophotometer (FP 8600, manufactured by japan spectrophotometers) was used. Fig. 12 shows the measurement results of the absorption spectrum and the emission spectrum of the obtained toluene solution. The horizontal axis represents wavelength and the vertical axis represents absorption intensity.

From the results shown in FIG. 12, it is understood that the toluene solution of 7mBP-3mDBtPBfpd has absorption peaks at about 333nm and 281nm and a luminescence wavelength peak at about 368 nm.

It can be said that the organic compound 7mBP-3mDBtPBfpd according to one embodiment of the present invention has a high T1 level and is suitable as a host material for a phosphorescent material (guest material) which emits light in the vicinity of green. Note that the organic compound 7mBP-3mDBtPBfpd which is one embodiment of the present invention can also be used as a host material or a light-emitting substance of a phosphorescent light-emitting substance in a visible region.

Claims

1. An organic compound represented by the general formula (G1).

[ chemical formula 1]

(in the general formula, Q represents oxygen or sulfur, and A is a group having 12 to 100 total carbon atoms and having one or more of a heteroaromatic ring including a benzene ring, a naphthalene ring, a fluorene ring, a phenanthrene ring, a triphenylene ring, a dibenzothiophene ring, a heteroaromatic ring including a dibenzofuran ring, a heteroaromatic ring including a carbazole ring, a benzimidazole ring, and a triphenylamine structure¹To R⁵Each independently represents hydrogen, an alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted monocyclic saturated hydrocarbon having 5 to 7 carbon atoms, a substituted or unsubstituted polycyclic saturated hydrocarbon having 7 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 13 carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 to 12 carbon atoms. )

2. An organic compound represented by the general formula (G2).

[ chemical formula 2]

(in the formula, Q represents oxygen or sulfur.In addition, α represents a substituted or unsubstituted phenylene group, and n represents an integer of 0 to 4. In addition, Ht_uniRepresents a skeleton having a hole-transporting property. In addition, R¹To R⁵Represents hydrogen, an alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted monocyclic saturated hydrocarbon having 5 to 7 carbon atoms, a substituted or unsubstituted polycyclic saturated hydrocarbon having 7 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 13 carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 to 12 carbon atoms. )

3. An organic compound represented by the general formula (G3).

[ chemical formula 3]

(in the formula, Q represents oxygen or sulfur; further, Ht_uniRepresents a skeleton having a hole-transporting property. In addition, R¹To R⁵Represents hydrogen, an alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted monocyclic saturated hydrocarbon having 5 to 7 carbon atoms, a substituted or unsubstituted polycyclic saturated hydrocarbon having 7 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 13 carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 to 12 carbon atoms. )

4. The organic compound according to claim 2 or 3,

wherein the Ht_uniHas any one of a pyrrole ring structure, a furan ring structure and a thiophene ring structure.

5. The organic compound according to any one of claims 2 to 4,

wherein the Ht_uniRepresented by any one of the following general formulae (Ht-1) to (Ht-26).

[ chemical formula 4]

[ chemical formula 5]

(in the formula, Q represents oxygen or sulfur, and R²To R⁷¹Each represents a substituent of 1 to 4, and each independently represents any of hydrogen, an alkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted phenyl group. In addition, Ar¹Represents a substituted or unsubstituted aryl group having 6 to 13 carbon atoms. )

6. An organic compound represented by structural formula (100) or (101).

[ chemical formula 6]

7. A light-emitting device comprising the organic compound according to any one of claims 1 to 6.

8. A light emitting device comprising:

an EL layer between a pair of electrodes,

wherein the EL layer includes the organic compound according to any one of claims 1 to 6.

9. A light emitting device comprising:

an EL layer between a pair of electrodes,

wherein the EL layer includes a light emitting layer,

and the light-emitting layer includes the organic compound described in any one of claims 1 to 6.

10. A light emitting device comprising:

an EL layer between a pair of electrodes,

wherein the EL layer includes a light emitting layer,

further, the light-emitting layer includes the organic compound according to any one of claims 1 to 6 and a phosphorescent material.

11. A light emitting device comprising:

an EL layer between a pair of electrodes,

wherein the EL layer includes a light emitting layer,

and the light-emitting layer includes the organic compound according to any one of claims 1 to 6, a phosphorescent material, and a carbazole derivative.

12. The light-emitting device as set forth in claim 11,

wherein the carbazole derivative is a bicarbazole derivative.

13. A light emitting device comprising:

the light-emitting device of any one of claims 7 to 12; and

at least one of a transistor and a substrate.

14. An electronic device, comprising:

the light-emitting device according to claim 13; and

at least one of a microphone, a camera, an operation button, an external connection portion, and a speaker.

15. An illumination device, comprising:

the light-emitting device of any one of claims 7 to 12; and

at least one of a housing, a cover, and a support table.