JP2019142821A - Method of synthesizing organic compound having fused carbazole skeleton - Google Patents

Abstract

To provide a synthesis method that increases the yield of an organic compound having a fused carbazole skeleton.SOLUTION: In synthesis of an organic compound having a fused carbazole skeleton, the chlorine content in a compound having a fused carbazole skeleton used as an ingredient is made 10 ppm or less thereby allowing increase of the yield of the organic compound having the fused carbazole skeleton.SELECTED DRAWING: None

Description

One embodiment of the present invention relates to a method for synthesizing an organic compound having a condensed carbazole skeleton. In particular, the present invention relates to a method for synthesizing an organic compound having a condensed carbazole skeleton that can be synthesized at a higher yield than conventional. Note that one embodiment of the present invention is not limited to the above 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, a machine, a manufacture, or a composition (composition of matter). Specifically, a semiconductor device, a display device, a liquid crystal display device, and the like can be given as examples.

A light emitting mechanism of an organic EL element (light emitting element) formed by sandwiching an EL layer containing a light emitting substance between a pair of electrodes is a carrier injection type. That is, when a voltage is applied between the electrodes, electrons and holes injected from the electrodes are recombined to make the luminescent substance in an excited state and emit light when the excited state returns to the ground state. The types of excited states include a singlet excited state (S ^* ) and a triplet excited state (T ^* ). Light emitted from the singlet excited state is fluorescent, and light emitted from the triplet excited state is phosphorescent. being called. In addition, the statistical generation ratio of the light emitting elements is considered to be S ^* : T ^* = 1: 3.

Among the above luminescent substances, compounds that can convert energy in singlet excited state into light emission are called fluorescent compounds (fluorescent materials), and can convert energy in triplet excited state into light emission. Such a compound is called a phosphorescent compound (phosphorescent material).

Such light-emitting elements are often produced using a plurality of types of organic compounds in addition to the above light-emitting substances, and are effective in improving the element characteristics, and various reports have been made. (For example, refer to Patent Document 1).

JP 2010-182699 A

Organic compounds used for light-emitting elements have a variety of synthesis methods, and different synthesis methods can be used even when the same substance is synthesized. However, when the synthesis method is different, since the raw materials, catalysts, and the like to be used are different, problems such as differences in the yield and purity of the product arise. Since the cost of a light-emitting element can be reduced by using an organic compound with a high synthesis yield for the light-emitting element, one embodiment of the present invention provides a synthesis method for increasing the yield of an organic compound having a condensed carbazole skeleton. For the purpose. In addition, since the purity of the organic compound used for the light-emitting element affects the characteristics of the light-emitting element, an object of one embodiment of the present invention is to provide a method for efficiently synthesizing an organic compound having a condensed carbazole skeleton with high purity. And Note that the description of these problems does not disturb the existence of other problems. Note that one embodiment of the present invention does not necessarily have to solve all of these problems. Issues other than these will be apparent from the description of the specification, drawings, claims, etc., and other issues can be extracted from the descriptions of the specification, drawings, claims, etc. It is.

In one embodiment of the present invention, in the synthesis of an organic compound having a condensed carbazole skeleton, the yield of the organic compound having a condensed carbazole skeleton is increased by reducing the chlorine content in the compound having the condensed carbazole skeleton used as a raw material. It is a synthesis method that can.

Usually, a compound having a condensed carbazole skeleton as a raw material is obtained by an oxidation reaction using an oxidant, but the inventors have determined what kind of oxidant is used in the synthesis of the raw material, and an organic compound having a condensed carbazole skeleton. It was found to affect the yield of synthesis. That is, by synthesizing a compound having a condensed carbazole skeleton having a chlorine content of 10 ppm or less using an oxidizing agent not containing chlorine, and using this as a raw material, the yield of an organic compound having a condensed carbazole skeleton is increased. Can do.

Accordingly, one embodiment of the present invention is a condensed carbazole skeleton characterized by coupling a compound having a condensed carbazole skeleton having a chlorine content of 10 ppm or less and a halogenated aryl compound or a halogenated heteroaryl compound. A method for synthesizing an organic compound having

Note that in the above structure, it is more preferable to use a compound having a condensed carbazole skeleton with a chlorine content of 5 ppm or less.

Another embodiment of the present invention is to combine a compound having a condensed carbazole skeleton represented by the following general formula (G0) with a chlorine content of 10 ppm or less, and a halogenated aryl compound or a halogenated heteroaryl compound. It is a method for synthesizing an organic compound having a condensed carbazole skeleton characterized by ringing.

In General Formula (G0), at least one of positions a to c or g to i has a condensed structure with a substituted or unsubstituted benzene ring. R ^{1 to 8} each independently represent hydrogen, an alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, and n and m each represent 1 to 4 Represents an integer.

Another embodiment of the present invention is to couple a compound having a condensed carbazole skeleton obtained by a synthesis method using a chlorine-free oxidizing agent and a halogenated aryl compound or a halogenated heteroaryl compound. This is a method for synthesizing an organic compound having a condensed carbazole skeleton.

In addition, as an oxidizing agent which does not contain chlorine, a quinone oxidizing agent which does not contain chlorine can be used. Specific examples of the oxidizing agent not containing chlorine include quinones such as 1,4-benzoquinone, manganese dioxide, nickel peroxide, sulfur, sulfur in the presence of dimethyl sulfoxide, and the like.

In one embodiment of the present invention, a synthesis method for increasing the yield of an organic compound having a condensed carbazole skeleton can be provided. In another embodiment of the present invention, a method for synthesizing an organic compound having a highly purified condensed carbazole skeleton can be provided. Note that the description of these effects does not disturb the existence of other problems. One embodiment of the present invention does not necessarily have to solve all of these problems. In addition, problems other than these will be apparent from the description of the specification, drawings, claims, etc., and other problems can be extracted from the description of the specifications, drawings, claims, etc. It is.

4A and 4B illustrate a structure of a light-emitting element. FIG. 6 illustrates a light-emitting device. FIG. 6 illustrates a light-emitting device. 6A and 6B illustrate electronic devices. 6A and 6B illustrate electronic devices. The figure explaining a motor vehicle. The figure explaining an illuminating device. 1H-NMR chart of 7H-dibenzo [c, g] carbazole. 1H-NMR chart of 7H-dibenzo [c, g] carbazole. 1H-NMR chart of cgDBCzPA. 1H-NMR chart of cgDBCzPA. The figure which shows MS spectrum.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to the following description, and various changes can be made in form and details without departing from the spirit and scope of the present invention. Therefore, the present invention should not be construed as being limited to the description of the embodiments below.

Note that the position, size, range, and the like of each component illustrated in the drawings and the like may not represent the actual position, size, range, or the like for easy understanding. Therefore, the disclosed invention is not necessarily limited to the position, size, range, or the like disclosed in the drawings and the like.

Further, in this specification and the like, in describing the structure of the invention with reference to the drawings, the same reference numerals are used in different drawings.

(Embodiment 1)
In this embodiment, a method for synthesizing an organic compound having a condensed carbazole skeleton, which is one embodiment of the present invention, will be described. Note that the organic compound having a condensed carbazole skeleton shown in this embodiment is represented by the following general formula (G1).

In general formula (G1), at least one of positions a to c or g to i has a condensed structure with a substituted or unsubstituted benzene ring. R ^{1 to 8} each independently represent hydrogen, an alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, and n and m each represent 1 to 4 Represents an integer. R ′ represents a group having a substituted or unsubstituted condensed ring or heterocyclic group having 10 to 30 carbon atoms via an arylene group having 6 to 14 carbon atoms.

In the synthesis of the organic compound having a condensed carbazole skeleton represented by the above general formula (G1), a double bond of the compound (G0) having a condensed carbazole skeleton used as a raw material is formed. The oxidation reaction using an oxidizing agent as shown in FIG.

In the above synthesis scheme (A-1), at least one of the positions a to c or g to i in the general formula of each substance has a condensed structure with a substituted or unsubstituted benzene ring. R ^{1 to 8} each independently represent hydrogen, an alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, and n and m each represent 1 to 4 Represents an integer.

Note that the method for synthesizing an organic compound having a condensed carbazole skeleton which is one embodiment of the present invention is characterized in that an oxidizing agent containing no chlorine is used in the reaction shown in the synthesis scheme (A-1). As the oxidizing agent not containing chlorine, for example, a quinone oxidizing agent can be used. Specific examples of the oxidizing agent not containing chlorine include quinones such as 1,4-benzoquinone, manganese dioxide, nickel peroxide, sulfur, sulfur in the presence of dimethyl sulfoxide, and the like.

Next, by coupling the compound (G0) having a condensed carbazole skeleton and the halide (R′-X), as shown in the following synthesis scheme (A-2), an organic compound (G1 ) Can be synthesized.

In the above synthesis scheme (A-2), at least one of positions a to c or g to i in the general formula of each substance has a condensed structure with a substituted or unsubstituted benzene ring. R ^{1 to 8} each independently represent hydrogen, an alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, and n and m each represent 1 to 4 Represents an integer. R ′ represents a group having a substituted or unsubstituted condensed ring or heterocyclic group having 10 to 30 carbon atoms via an arylene group having 6 to 14 carbon atoms. X represents halogen.

Note that in the method for synthesizing an organic compound having a condensed carbazole skeleton which is one embodiment of the present invention, a halide (R′-X) is used in the reaction shown in the synthesis scheme (A-2). Examples of the halide (R′-X) include a halogenated aryl compound and a halogenated heteroaryl compound. Specific examples of the halogenated aryl compound or the halogenated heteroaryl compound include 9- (4-bromophenyl) 10-phenylanthracene, 9- (4-bromophenyl) 10- (1-naphthyl) anthracene, and the like. Is mentioned.

Note that a substituted or unsubstituted benzene ring, substituted or unsubstituted in the above-described general formula (G0), the general formula (G1), or the substances shown in the synthesis scheme (A-1) and the synthesis scheme (A-2). When the aryl group having 6 to 18 carbon atoms and the substituted or unsubstituted condensed ring or heterocyclic ring having 10 to 30 carbon atoms each have a substituent, the substituent includes a methyl group, an ethyl group, a propyl group, and isopropyl. Group, butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, alkyl group having 1 to 7 carbon atoms, cyclopentyl group, cyclohexyl group, cycloheptyl group, 8,9, C5-C7 cycloalkyl group such as 10-trinorbornanyl group, 6-carbon group such as phenyl group, naphthyl group and biphenyl group And an aryl group of 12

Specific examples of the alkyl group having 1 to 6 carbon atoms in the substances represented by the general formula (G0), the general formula (G1), or the synthesis scheme (A-1) and the synthesis scheme (A-2) Are methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, isobutyl, tert-butyl, pentyl, isopentyl, sec-pentyl, tert-pentyl, neopentyl, hexyl Group, isohexyl group, 3-methylpentyl group, 2-methylpentyl group, 2-ethylbutyl group, 1,2-dimethylbutyl group, 2,3-dimethylbutyl group, and the like.

Specific examples of the aryl group having 6 to 18 carbon atoms in the substances represented by the above general formula (G0), general formula (G1), or the synthesis scheme (A-1) and the synthesis scheme (A-2) Are phenyl group, o-tolyl group, m-tolyl group, p-tolyl group, mesityl group, o-biphenyl group, m-biphenyl group, p-biphenyl group, 1-naphthyl group, 2-naphthyl group, fluorenyl group And triphenylenyl group.

Specific examples of the arylene group having 6 to 14 carbon atoms in R ′ in the general formula (G1) or the synthesis scheme (A-2) include a phenylene group, a biphenylene group, an anthrylene group, and a phenanthrene group. Can be mentioned.

Specific examples of the group having a condensed ring or heterocyclic group having 10 to 30 carbon atoms in R ′ in the general formula (G1) or the synthesis scheme (A-2) include anthracene, diphenylanthracene, and 9 -[4- (1-naphthyl) phenyl] anthracene and the like.

Next, a specific structural formula of an organic compound having a condensed carbazole skeleton, which is synthesized by the method for synthesizing an organic compound having a condensed carbazole skeleton, which is one embodiment of the present invention described above, is shown below. However, the present invention is not limited to these.

As described above, in this embodiment, an example of a method for synthesizing an organic compound having a condensed carbazole skeleton, which is one embodiment of the present invention, and an example of an organic compound having a condensed carbazole skeleton synthesized by the synthesis method have been described.

The structure described in this embodiment can be combined as appropriate with any of the structures described in the other embodiments.

(Embodiment 2)
In this embodiment, a light-emitting element to which the organic compound synthesized by the synthesis method described in Embodiment 1 can be applied is described with reference to FIGS.

≪Basic structure of light emitting element≫
First, the basic structure of the light emitting element will be described. FIG. 1A illustrates an example of a light-emitting element having an EL layer including a light-emitting layer between a pair of electrodes. Specifically, the EL layer 103 is sandwiched between the first electrode 101 and the second electrode 102.

In FIG. 1B, a plurality of (two layers in FIG. 1B) EL layers (103a and 103b) are provided between a pair of electrodes, and the charge generation layer 104 is provided between the EL layers. An example of a light-emitting element having a stacked structure (tandem structure) is shown. A light-emitting element having a tandem structure can realize a light-emitting device that can be driven at a low voltage and has low power consumption.

When a voltage is applied to the first electrode 101 and the second electrode 102, the charge generation layer 104 injects electrons into one EL layer (103a or 103b) and the other EL layer (103b or 103a). It has a function of injecting holes. Therefore, in FIG. 1B, when a voltage is applied to the first electrode 101 so that the potential is higher than that of the second electrode 102, electrons are injected from the charge generation layer 104 into the EL layer 103a, and the EL layer 103b. Holes are injected into the.

Note that the charge generation layer 104 has a property of transmitting visible light in terms of light extraction efficiency (specifically, the visible light transmittance of the charge generation layer 104 is 40% or more). preferable. In addition, the charge generation layer 104 functions even when it has lower conductivity than the first electrode 101 or the second electrode 102.

FIG. 1C illustrates a case where the EL layer 103 illustrated in FIG. 1A (the same applies to the case where the EL layers (103a and 103b) in FIG. 1B have a stacked structure) has a stacked structure. An example is shown. However, in this case, the first electrode 101 functions 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. Have Note that in the case where a plurality of EL layers are provided as illustrated in FIG. 1B, each EL layer has a structure in which layers are sequentially stacked from the anode side. Further, when the first electrode 101 is a cathode and the second electrode 102 is an anode, the stacking order of the EL layers is reversed.

The light-emitting layer 113 included in each of the EL layers (103, 103a, and 103b) includes a light-emitting substance and a plurality of substances as appropriate, and has a structure in which fluorescence emission or phosphorescence emission having a desired emission color can be obtained. it can. Alternatively, the light-emitting layer 113 may have a stacked structure with different emission colors. Note that in this case, different materials may be used for the light-emitting substance and other substances used for the stacked light-emitting layers. Alternatively, different light emission colors may be obtained from the plurality of EL layers (103a and 103b) illustrated in FIG. In this case as well, the light-emitting substance and other substances used for each light-emitting layer may be different materials.

In the light-emitting element, for example, the first electrode 101 illustrated in FIG. 1C is a reflective electrode, the second electrode 102 is a semi-transmissive / semi-reflective electrode, and a micro optical resonator (microcavity) structure is formed. Thus, light emission obtained from the light-emitting layer 113 included in the EL layer 103 can be resonated between both electrodes, and light emission obtained from the second electrode 102 can be strengthened.

Note that in the case where the first electrode 101 of the light-emitting element is a reflective electrode having a stacked structure of a reflective conductive material and a light-transmitting conductive material (transparent conductive film), a film of the transparent conductive film Optical adjustment can be performed by controlling the thickness. Specifically, the distance between the first electrode 101 and the second electrode 102 is near mλ / 2 (where m is a natural number) with respect to the wavelength λ of light obtained from the light-emitting layer 113. It is preferable to adjust as follows.

Further, in order to amplify desired light (wavelength: λ) obtained from the light emitting layer 113, an optical distance from the first electrode 101 to a region (light emitting region) where the desired light of the light emitting layer 113 can be obtained, The optical distance from the second electrode 102 to the region (light emitting region) where desired light can be obtained from the light emitting layer 113 is adjusted to be close to (2m ′ + 1) λ / 4 (where m ′ is a natural number). It is preferable to do this. Note that the light emitting region herein refers to a recombination region between holes and electrons in the light emitting layer 113.

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

However, in the above case, the optical distance between the first electrode 101 and the second electrode 102 is strictly the total thickness from the reflective region of the first electrode 101 to the reflective region of the second electrode 102. it can. However, since it is difficult to precisely determine the reflection region in the first electrode 101 or the second electrode 102, it is assumed that any position of the first electrode 101 and the second electrode 102 is the reflection region. The above-mentioned effect can be sufficiently obtained. Strictly speaking, the optical distance between the first electrode 101 and the light emitting layer from which desired light can be obtained is the optical distance between the reflective region in the first electrode 101 and the light emitting region in the light emitting layer from which desired light can be obtained. It can be said that it is a distance. However, since it is difficult to strictly determine the reflection region in the first electrode 101 and the light-emitting region in the light-emitting layer from which desired light can be obtained, any position of the first electrode 101 can be set as the reflection region, the desired region. It is assumed that the above-described effect can be sufficiently obtained by assuming an arbitrary position of the light emitting layer from which light is obtained as a light emitting region.

Note that in the case where the light-emitting element illustrated in FIG. 1C has a microcavity structure, light having different wavelengths (monochromatic light) can be extracted even if the light-emitting element has the same EL layer. Accordingly, there is no need for separate coloring (for example, RGB) for obtaining different emission colors. Moreover, it is easy to realize high definition. A combination with a colored layer (color filter) is also possible. Furthermore, since it is possible to increase the emission intensity of the specific wavelength in the front direction, it is possible to reduce power consumption.

The light-emitting element illustrated in FIG. 1E is an example of the light-emitting element having the tandem structure illustrated in FIG. 1B. As illustrated, three EL layers (103a, 103b, and 103c) are charge generation layers. (104a, 104b). Note that the three EL layers (103a, 103b, and 103c) each have a light emitting layer (113a, 113b, and 113c), and the light emission colors of the light emitting layers can be freely combined. For example, the light-emitting layer 113a can be blue, the light-emitting layer 113b can be red, green, or yellow, and the light-emitting layer 113c can be blue, but the light-emitting layer 113a can be red and the light-emitting layer 113b can be blue, green, or yellow. In any case, the light emitting layer 113c may be red.

Note that in the above light-emitting element, at least one of the first electrode 101 and the second electrode 102 is a light-transmitting electrode (a transparent electrode, a semi-transmissive / semi-reflective electrode, or the like). When the light-transmitting electrode is a transparent electrode, the transparent electrode has a visible light transmittance of 40% or more. In the case of a semi-transmissive / semi-reflective electrode, the visible light reflectance of the semi-transmissive / semi-reflective electrode is 20% to 80%, preferably 40% to 70%. These electrodes preferably have a resistivity of 1 × 10 ⁻² Ωcm or less.

In the above light-emitting element, when one of the first electrode 101 and the second electrode 102 is a reflective electrode (reflective electrode), the reflectance of visible light of the reflective electrode is 40 % To 100%, preferably 70% to 100%. The electrode preferably has a resistivity of 1 × 10 ⁻² Ωcm or less.

<< Specific structure and manufacturing method of light-emitting element >>
Next, a specific structure and manufacturing method of the light-emitting element illustrated in FIGS. Note that here, not only the light-emitting element in which the EL layer 103 has a single-layer structure as shown in FIGS. 1A and 1C, but also FIGS. 1B, 1D, and 1C. The light-emitting element having the tandem structure shown in E) will be described together. In the case where each light-emitting element shown in FIG. 1 has a microcavity structure, for example, the first electrode 101 may be formed as a reflective electrode, and the second electrode 102 may be formed as a semi-transmissive / semi-reflective electrode. Further, a desired electrode material can be formed by using a single layer or a plurality of layers and forming a single layer or a stacked layer. The second electrode 102 is formed by selecting a material in the same manner as described above after the EL layer (103, 103b) is formed. In addition, a sputtering method or a vacuum evaporation method can be used for manufacturing these electrodes.

<First electrode and second electrode>
As materials for forming the first electrode 101 and the second electrode 102, the following materials can be used in appropriate combination as long as the functions of both electrodes described above can be satisfied. For example, a metal, an alloy, an electrically conductive compound, a mixture thereof, and the like can be used as appropriate. Specifically, 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 can be given. In addition, 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 ), A metal such as neodymium (Nd), and an alloy containing an appropriate combination thereof. In addition, elements belonging to Group 1 or Group 2 of the periodic table of elements not exemplified above (for example, lithium (Li), cesium (Cs), calcium (Ca), strontium (Sr)), europium (Eu), ytterbium Rare earth metals such as (Yb), alloys containing these in appropriate combinations, other graphene, and the like can be used.

When the first electrode 101 is an anode, the hole injection layer (111, 111a) and the hole transport layer (112, 112a) of the EL layer (103, 103a) are formed on the first electrode 101 by a vacuum deposition method. The layers are sequentially stacked. Note that in the case of the light-emitting element having a tandem structure illustrated in FIG. 1D, after the EL layer 103a and the charge generation layer 104 are sequentially formed, the hole injection layer 111b of the EL layer 103b and the charge generation layer 104 are formed. Similarly, the hole transport layer 112b is sequentially stacked.

<Hole injection layer and hole transport layer>
The hole injection layer (111, 111a, 111b) is a layer for injecting holes from the first electrode 101 serving as an anode or the charge generation layer (104) into the EL layers (103, 103a, 103b). , A layer containing a material having a high hole injection property.

Examples of the material having a high hole injection property include transition metal oxides such as molybdenum oxide, vanadium oxide, ruthenium oxide, tungsten oxide, and manganese oxide. In addition, phthalocyanine compounds such as phthalocyanine (abbreviation: H ₂ Pc) and copper phthalocyanine (abbreviation: CuPC), 4,4′-bis [N- (4-diphenylaminophenyl) -N-phenylamino] biphenyl ( Abbreviation: DPAB), N, N′-bis {4- [bis (3-methylphenyl) amino] phenyl} -N, N′-diphenyl- (1,1′-biphenyl) -4,4′-diamine ( An aromatic amine compound such as abbreviation (DNTPD) or a polymer such as poly (3,4-ethylenedioxythiophene) / poly (styrenesulfonic acid) (abbreviation: PEDOT / PSS) can be used.

As a material having a high hole-injecting property, a composite material including a hole-transporting material and an acceptor material (electron-accepting material) can also be used. In this case, electrons are extracted from the hole transporting material by the acceptor material, and holes are generated in the hole injection layer (111, 111a, 111b), via the hole transporting layer (112, 112a, 112b). Holes are injected into the light emitting layer (113, 113a, 113b). Note that the hole injection layer (111, 111a, 111b) may be formed as a single layer made of a composite material including a hole transporting material and an acceptor material (electron accepting material). The material and the acceptor material (electron-accepting material) may be stacked in separate layers.

The hole transport layer (112, 112a, 112b) is configured to transfer holes injected from the first electrode 101 or the charge generation layer 104 by the hole injection layer (111, 111a, 111b) to the light emitting layer (113, 113a, 113b). Note that the hole transport layers (112, 112a, 112b) are layers containing a hole transport material. As the hole transporting material used for the hole transport layer (112, 112a, 112b), a material having a HOMO level that is the same as or close to the HOMO level of the hole injection layer (111, 111a, 111b) should be used. Is preferred.

As an acceptor material used for the hole-injection layer (111, 111a, 111b), an oxide of a metal belonging to Groups 4 to 8 in the periodic table can be used. Specific examples include molybdenum oxide, vanadium oxide, niobium oxide, tantalum oxide, chromium oxide, tungsten oxide, manganese oxide, and rhenium oxide. Among these, molybdenum oxide is especially preferable because it is stable in the air, has a low hygroscopic property, and is easy to handle. In addition, organic acceptors such as quinodimethane derivatives, chloranil derivatives, and hexaazatriphenylene derivatives can be used. As those having an electron-withdrawing group (halogen group or cyano group), 7,7,8,8-tetracyano-2,3,5,6-tetrafluoroquinodimethane (abbreviation: F ₄ -TCNQ), chloranil, 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene (approximately: HAT-CN), 1,3,4,5,7,8- And hexafluorotetracyano-naphthoquinodimethane (abbreviation: F6-TCNNQ). In particular, a compound in which an electron withdrawing group is bonded to a condensed aromatic ring having a plurality of heteroatoms such as HAT-CN is preferable because it is thermally stable. [3] Radialene derivatives having an electron-withdrawing group (particularly a halogen group such as a fluoro group or a cyano group) are preferable because of their very high electron-accepting properties. Specifically, α, α ′, α ″ − 1,2,3-cyclopropanetriylidenetris [4-cyano-2,3,5,6-tetrafluorobenzeneacetonitrile], α, α ′, α ″ -1,2,3-cyclopropanetriylidenetris [2,6-dichloro-3,5-difluoro-4- (trifluoromethyl) benzeneacetonitrile], α, α ′, α ″ -1,2,3-cyclopropanetriylidentris [2,3,4 , 5,6-pentafluorobenzeneacetonitrile] and the like.

As a hole transporting material used for the hole injection layer (111, 111a, 111b) and the hole transport layer (112, 112a, 112b), a substance having a hole mobility of 10 ⁻⁶ cm ² / Vs or more is used. preferable. Note that other than these substances, any substance that has a property of transporting more holes than electrons can be used.

As the hole transporting material, a π-electron rich heteroaromatic compound (for example, a carbazole derivative or an indole derivative) or an aromatic amine compound is preferable. As a specific example, 4,4′-bis [N- (1-naphthyl) is preferable. ) -N-phenylamino] biphenyl (abbreviation: NPB or α-NPD), N, N′-bis (3-methylphenyl) -N, N′-diphenyl- [1,1′-biphenyl] -4,4 '-Diamine (abbreviation: TPD), 4,4'-bis [N- (spiro-9,9'-bifluoren-2-yl) -N-phenylamino] biphenyl (abbreviation: BSPB), 4-phenyl-4 '-(9-phenylfluoren-9-yl) triphenylamine (abbreviation: BPAFLP), 4-phenyl-3'-(9-phenylfluoren-9-yl) triphenylamine (abbreviation: m BPAFLP), 4-phenyl-4 ′-(9-phenyl-9H-carbazol-3-yl) triphenylamine (abbreviation: PCBA1BP), 3- [4- (9-phenanthryl) -phenyl] -9-phenyl- 9H-carbazole (abbreviation: PCPPn), N- (4-biphenyl) -N- (9,9-dimethyl-9H-fluoren-2-yl) -9-phenyl-9H-carbazol-3-amine (abbreviation: PCBiF) ), N- (1,1′-biphenyl-4-yl) -N- [4- (9-phenyl-9H-carbazol-3-yl) phenyl] -9,9-dimethyl-9H-fluorene-2- Amine (abbreviation: PCBBiF), 4,4′-diphenyl-4 ″-(9-phenyl-9-H-carbazol-3-yl) triphenylamine (abbreviation: PCBBi1B) ), 4- (1-naphthyl) -4 ′-(9-phenyl-9H-carbazol-3-yl) triphenylamine (abbreviation: PCBANB), 4,4′-di (1-naphthyl) -4 ″ -(9-phenyl-9H-carbazol-3-yl) triphenylamine (abbreviation: PCBNBB), 9,9-dimethyl-N-phenyl-N- [4- (9-phenyl-9H-carbazol-3-yl) ) Phenyl] -fluoren-2-amine (abbreviation: PCBAF), N-phenyl-N- [4- (9-phenyl-9H-carbazol-3-yl) phenyl] spiro-9,9′-bifluoren-2- Amine (abbreviation: PCBASF), 4,4 ′, 4 ″ -tris (carbazol-9-yl) triphenylamine (abbreviation: TCTA), 4,4 ′, 4 ″ -tris (N, N-diphe) Ruamino) triphenylamine (abbreviation: TDATA), 4,4 ′, 4 ″ -tris [N- (3-methylphenyl) -N-phenylamino] triphenylamine (abbreviation: MTDATA), 4,4′- A compound having an aromatic amine skeleton such as bis [N- (spiro-9,9′-bifluoren-2-yl) -N-phenylamino] biphenyl (abbreviation: BSPB), 1,3-bis (N-carbazolyl) Benzene (abbreviation: mCP), 4,4′-di (N-carbazolyl) biphenyl (abbreviation: CBP), 3,6-bis (3,5-diphenylphenyl) -9-phenylcarbazole (abbreviation: CzTP), 3 , 3′-bis (9-phenyl-9H-carbazole) (abbreviation: PCCP), 3- [N- (9-phenylcarbazol-3-yl) -N-phenylamino]- 9-phenylcarbazole (abbreviation: PCzPCA1), 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), 1,3,5-tris [4- (N-carbazolyl) phenyl] benzene ( Abbreviations: TCPB), 9- [4- (10-phenyl-9-anthracenyl) phenyl] -9H-carbazole (abbreviation: CzPA) and other compounds having a carbazole skeleton, 4,4 ′, 4 ″-(benzene- 1,3,5-triyl) tri (dibenzothiophene) (abbreviation: DBT3P-II), 2,8-diphenyl-4- [4- (9 Phenyl-9H-fluoren-9-yl) phenyl] dibenzothiophene (abbreviation: DBTFLP-III), 4- [4- (9-phenyl-9H-fluoren-9-yl) phenyl] -6-phenyldibenzothiophene (abbreviation) : DBTFLP-IV) and other compounds having a thiophene skeleton, 4,4 ′, 4 ″-(benzene-1,3,5-triyl) tri (dibenzofuran) (abbreviation: DBF3P-II), 4- {3- And compounds having a furan skeleton such as [3- (9-phenyl-9H-fluoren-9-yl) phenyl] phenyl} dibenzofuran (abbreviation: mmDBFFLBi-II).

Further, poly (N-vinylcarbazole) (abbreviation: PVK), poly (4-vinyltriphenylamine) (abbreviation: PVTPA), poly [N- (4- {N ′-[4- (4-diphenylamino)] Phenyl] phenyl-N′-phenylamino} phenyl) methacrylamide] (abbreviation: PTPDMA) poly [N, N′-bis (4-butylphenyl) -N, N′-bis (phenyl) benzidine] (abbreviation: Poly High molecular compounds such as -TPD) can also be used.

However, the hole transporting material is not limited to the above, and a hole injection layer (111, 111a, 111b) and a hole transporting layer may be used as a hole transporting material by combining one or more known various materials. (112, 112a, 112b). Note that each of the hole transport layers (112, 112a, 112b) may be formed of a plurality of layers. That is, the first hole transport layer and the second hole transport layer may be laminated.

In the light emitting element shown in FIG. 1, the light emitting layers (113, 113a) are formed on the hole transport layers (112, 112a) of the EL layers (103, 103a) by a vacuum deposition method. Note that in the case of the light-emitting element having a tandem structure illustrated in FIG. 1D, after the EL layer 103a and the charge generation layer 104 are formed, the light-emitting layer 113b is also formed on the hole-transport layer 112b of the EL layer 103b. It is formed by a vapor deposition method.

<Light emitting layer>
The light emitting layers (113, 113a, 113b, 113c) are layers containing a light emitting substance. Note that as the light-emitting substance, a substance exhibiting a luminescent color such as blue, purple, blue-violet, green, yellow-green, yellow, orange, or red is appropriately used. In addition, by using different light emitting substances for the plurality of light emitting layers (113a, 113b, 113c), a structure exhibiting different light emission colors (for example, white light emission obtained by combining light emission colors having complementary colors) can be obtained. . Furthermore, a stacked structure in which one light emitting layer includes different light emitting substances may be used.

Further, the light emitting layer (113, 113a, 113b, 113c) may include one or more organic compounds (host material, assist material) in addition to the light emitting substance (guest material). As the one or more kinds of organic compounds, one or both of a hole transporting material and an electron transporting material described in this embodiment can be used.

As a light-emitting substance that can be used for the light-emitting layers (113, 113a, 113b, and 113c), a light-emitting substance that changes singlet excitation energy into light emission in the visible light region, or light emission that changes triplet excitation energy into light emission in the visible light region. Substances can be used.

Examples of other luminescent substances include the following.

Examples of the light-emitting substance that converts singlet excitation energy into light emission include substances that emit fluorescence (fluorescent materials). For example, pyrene derivatives, anthracene derivatives, triphenylene derivatives, fluorene derivatives, carbazole derivatives, dibenzothiophene derivatives, dibenzofuran derivatives, dibenzos Examples include quinoxaline derivatives, quinoxaline derivatives, pyridine derivatives, pyrimidine derivatives, phenanthrene derivatives, and naphthalene derivatives. In particular, a pyrene derivative is preferable because of its high emission quantum yield. 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 (abbreviation: 1,6 mM emFLPAPrn), (N, N'-diphenyl-N, N'-bis [4- (9-phenyl-9H-fluoren-9-yl) phenyl] pyrene-1,6-diamine) (Abbreviation: 1,6FLPAPrn), N, N′-bis (dibenzofuran-2-yl) -N, N′-diphenylpyrene-1,6-diamine (abbreviation: 1,6FrAPrn), N, N′-bis ( Dibenzothiophen-2-yl) -N, N′-diphenylpyrene-1,6-diamine (abbreviation: 1,6ThAPrn), N, N ′-(pyrene-1,6-diyl) bis [(N-phenylbenzo [ ] Naphtho [1,2-d] furan) -6-amine] (abbreviation: 1,6BnfAPrn), N, N ′-(pyrene-1,6-diyl) bis [(N-phenylbenzo [b] naphtho [ 1,2-d] furan) -8-amine] (abbreviation: 1,6BnfAPrn-02), N, N ′-(pyrene-1,6-diyl) bis [(6, N-diphenylbenzo [b] naphtho And [1,2-d] furan) -8-amine] (abbreviation: 1,6BnfAPrn-03).

In addition, 5,6-bis [4- (10-phenyl-9-anthryl) phenyl] -2,2′-bipyridine (abbreviation: PAP2BPy), 5,6-bis [4 ′-(10-phenyl-) 9-anthryl) biphenyl-4-yl] -2,2′-bipyridine (abbreviation: PAPP2BPy), N, N′-bis [4- (9H-carbazol-9-yl) phenyl] -N, N′-diphenyl Stilbene-4,4′-diamine (abbreviation: YGA2S), 4- (9H-carbazol-9-yl) -4 ′-(10-phenyl-9-anthryl) triphenylamine (abbreviation: YGAPA), 4- ( 9H-carbazol-9-yl) -4 ′-(9,10-diphenyl-2-anthryl) triphenylamine (abbreviation: 2YGAPPA), N, 9-diphenyl-N- [4- (10 Phenyl-9-anthryl) phenyl] -9H-carbazol-3-amine (abbreviation: PCAPA), 4- (10-phenyl-9-anthryl) -4 ′-(9-phenyl-9H-carbazol-3-yl) Triphenylamine (abbreviation: PCBAPA), 4- [4- (10-phenyl-9-anthryl) phenyl] -4 ′-(9-phenyl-9H-carbazol-3-yl) triphenylamine (abbreviation: PCBAPBA) Perylene, 2,5,8,11-tetra-tert-butylperylene (abbreviation: TBP), N, N ″-(2-tert-butylanthracene-9,10-diyldi-4,1-phenylene) bis [N, N ′, N′-triphenyl-1,4-phenylenediamine] (abbreviation: DPABPA), N, 9-diphenyl-N- [4- (9 10-diphenyl-2-anthryl) phenyl] -9H-carbazol-3-amine (abbreviation: 2PCAPPA), N- [4- (9,10-diphenyl-2-anthryl) phenyl] -N, N ′, N ′ -Triphenyl-1,4-phenylenediamine (abbreviation: 2DPAPPA) or the like can be used.

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

Examples of phosphorescent materials include organometallic complexes, metal complexes (platinum complexes), and rare earth metal complexes. Since these exhibit different emission colors (emission peaks) for each substance, they are appropriately selected and used as necessary.

Examples of phosphorescent materials that exhibit blue or green color and whose emission spectrum peak wavelength is 450 nm or more and 570 nm or less include the following substances.

For example, tris {2- [5- (2-methylphenyl) -4- (2,6-dimethylphenyl) -4H-1,2,4-triazol-3-yl-κN2] phenyl-κC} iridium (III ) (Abbreviation: [Ir (mpppz-dmp) ₃ ]), tris (5-methyl-3,4-diphenyl-4H-1,2,4-triazolato) iridium (III) (abbreviation: [Ir (Mptz) ₃ ], Tris [4- (3-biphenyl) -5-isopropyl-3-phenyl-4H-1,2,4-triazolate] iridium (III) (abbreviation: [Ir (iPrptz-3b) ₃ ]), tris [3- (5-biphenyl) -5-isopropyl-4-phenyl-4H-1,2,4-triazolato] iridium (III) _{(abbreviation: [Ir (iPr5btz) 3]} ), like An organometallic complex having a 4H-triazole skeleton, tris [3-methyl-1- (2-methylphenyl) -5-phenyl-1H-1,2,4-triazolato] iridium (III) (abbreviation: [Ir (Mptz1 -Mp) ₃ ]), tris (1-methyl-5-phenyl-3-propyl-1H-1,2,4-triazolate) iridium (III) (abbreviation: [Ir (Prptz1-Me) ₃ ]) An organometallic complex 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] phenanthridinato] iridium (III) (abbreviated _{: [Ir (dmpimpt-Me)} 3] an organometallic complex having an imidazole skeleton, such as), bis [2- (4 ', 6'-difluorophenyl) pyridinato -N, C ^2'] iridium (III) tetrakis ( 1-pyrazolyl) borate (abbreviation: FIr6), bis [2- (4 ′, 6′-difluorophenyl) pyridinato-N, C ^{2 ′} ] iridium (III) picolinate (abbreviation: FIrpic), bis {2- [3 ', 5'-bis (trifluoromethyl) phenyl] pyridinato-N, C ^2' } iridium (III) picolinate (abbreviation: [Ir (CF ₃ ppy) ₂ (pic)]), bis [2- (4 ′ , 6'-difluorophenyl) pyridinato -N, C ^{2 ']} iridium (III) acetylacetonate (abbreviation: FIr (acac) an electron withdrawing group such as) Organometallic complexes of phenylpyridine derivative as a ligand are exemplified.

Examples of the phosphorescent material which exhibits green or yellow and has an emission spectrum peak wavelength of 495 nm or more and 590 nm or less include the following substances.

For example, tris (4-methyl-6-phenylpyrimidinato) iridium (III) (abbreviation: [Ir (mppm) ₃ ]), tris (4-t-butyl-6-phenylpyrimidinato) iridium (III) (Abbreviation: [Ir (tBupppm) ₃ ]), (acetylacetonato) bis (6-methyl-4-phenylpyrimidinato) iridium (III) (abbreviation: [Ir (mppm) ₂ (acac)]), ( Acetylacetonato) bis (6-tert-butyl-4-phenylpyrimidinato) iridium (III) (abbreviation: [Ir (tBupppm) ₂ (acac)]), (acetylacetonato) bis [6- (2- Norbornyl) -4-phenylpyrimidinato] iridium (III) (abbreviation: [Ir (nbppm) ₂ (acac)]), (acetylacetona G) Bis [5-methyl-6- (2-methylphenyl) -4-phenylpyrimidinato] iridium (III) (abbreviation: [Ir (mpmppm) ₂ (acac)]), (acetylacetonato) bis { 4,6-dimethyl-2- [6- (2,6-dimethylphenyl) -4-pyrimidinyl-κN3] phenyl-κC} iridium (III) (abbreviation: [Ir (dmppm-dmp) ₂ (acac)]) , (Acetylacetonato) bis (4,6-diphenylpyrimidinato) iridium (III) (abbreviation: [Ir (dppm) ₂ (acac)]), an organometallic iridium complex having a pyrimidine skeleton, isocyanatomethyl) bis (3,5-dimethyl-2-phenylpyrazinato) iridium (III) _{(abbreviation: [Ir (mppr-Me)} 2 (acac ]), (Acetylacetonato) bis (5-isopropyl-3-methyl-2-phenylpyrazinato) iridium (III) (abbreviation: [Ir _(mppr-iPr) pyrazine skeleton, such as 2 (acac)]) , Tris (2-phenylpyridinato-N, C ^{2 ′} ) iridium (III) (abbreviation: [Ir (ppy) ₃ ]), bis (2-phenylpyridinato-N, C ^{2 ′} ) iridium (III) acetylacetonate (abbreviation: [Ir (ppy) ₂ (acac)]), bis (benzo [h] quinolinato) iridium (III) acetylacetonate (abbreviation: [Ir (bzq) ₂ ( acac)]), tris (benzo [h] quinolinato) iridium (III) _{(abbreviation: [Ir (bzq) 3]} ), tris (2-Fenirukinori DOO -N, C ^{2 ')} iridium (III) _{(abbreviation: [Ir (pq) 3]} ), bis (2-phenylquinolinato--N, C ^2') iridium (III) acetylacetonate (abbreviation: [Ir (Pq) ₂ (acac)]), bis [2- (2-pyridinyl-κN) phenyl-κC] [2- (4-phenyl-2-pyridinyl-κN) phenyl-κC] iridium (III) (abbreviation: [Ir (ppy) ₂ (4dppy)]), bis [2- (2-pyridinyl-κN) phenyl-κC] [2- (4-methyl-5-phenyl-2-pyridinyl-κN) phenyl-κC] An organometallic iridium complex having such a pyridine skeleton, bis (2,4-diphenyl-1,3-oxazolate-N, C ^{2 ′} ) iridium (III) acetylacetonate (abbreviation: [Ir (dpo) ₂ (Acac)]), bis {2- [4 ′-(perfluorophenyl) phenyl] pyridinato-N, C ^{2 ′} } iridium (III) acetylacetonate (abbreviation: [Ir (p-PF-ph) ₂ ( acac)]), bis (2-phenylbenzothiazolate-N, C ^{2 ′} ) iridium (III) acetylacetonate (abbreviation: [Ir (bt) ₂ (acac)]) And a rare earth metal complex such as tris (acetylacetonato) (monophenanthroline) terbium (III) (abbreviation: [Tb (acac) ₃ (Phen)]).

Examples of the phosphorescent material which exhibits yellow or red and has an emission spectrum peak wavelength of 570 nm or more and 750 nm or less include the following substances.

For example, (diisobutyrylmethanato) bis [4,6-bis (3-methylphenyl) pyrimidinato] iridium (III) (abbreviation: [Ir (5 mdppm) ₂ (divm)]), bis [4,6-bis ( 3-methylphenyl) pyrimidinato] (dipivaloylmethanato) iridium (III) (abbreviation: [Ir (5 mdppm) ₂ (dpm)]), (dipivaloylmethanato) bis [4,6-di (naphthalene- Organometallic complexes having a pyrimidine skeleton such as 1-yl) pyrimidinato] iridium (III) (abbreviation: [Ir (d1npm) ₂ (dpm)]), (acetylacetonato) bis (2,3,5-triphenyl) Pirajinato) iridium (III) _{(abbreviation: [Ir (tppr) 2 (} acac)]), bis (2,3,5-triphenylpyrazinato (Dipivaloylmethanato) iridium (III) _{(abbreviation: [Ir (tppr) 2 (} dpm)]), bis {4,6-dimethyl-2- [3- (3,5-dimethylphenyl) -5- Phenyl-2-pyrazinyl-κN] phenyl-κC} (2,6-dimethyl-3,5-heptanedionato-κ ² O, O ′) iridium (III) (abbreviation: [Ir (dmdppr-P) ₂ (divm) ], Bis {4,6-dimethyl-2- [5- (4-cyano-2,6-dimethylphenyl) -3- (3,5-dimethylphenyl) -2-pyrazinyl-κN] phenyl-κC} (2,2,6,6-tetramethyl-3,5-heptanedionato-κ ² O, O ′) iridium (III) (abbreviation: [Ir (dmdppr-dmCP) ₂ (dpm)]), (acetylacetonato ) Screw [2 -Methyl-3-phenylquinoxalinato-N, C ^{2 ′} ] iridium (III) (abbreviation: [Ir (mpq) ₂ (acac)]), (acetylacetonato) bis (2,3-diphenylquinoxalinato -N, C2 ^' ) iridium (III) (abbreviation: [Ir (dpq) ₂ (acac)]), (acetylacetonato) bis [2,3-bis (4-fluorophenyl) quinoxalinato] iridium (III) (Abbreviation: [Ir (Fdpq) ₂ (acac)]) or an organometallic complex having a pyrazine skeleton, or tris (1-phenylisoquinolinato-N, C ^{2 ′} ) iridium (III) (abbreviation: [Ir (Piq) ₃ ]), bis (1-phenylisoquinolinato-N, C ^{2 ′} ) iridium (III) acetylacetonate (abbreviation: [Ir (piq) ₂ (aca c)])), pyridine such as bis [4,6-dimethyl-2- (2-quinolinyl-κN) phenyl-κC] (2,4-pentanedionato-κ ² O, O ′) iridium (III) Organometallic complexes having a skeleton, platinum complexes such as 2,3,7,8,12,13,17,18-octaethyl-21H, 23H-porphyrin platinum (II) (abbreviation: [PtOEP]), tris (1 , 3-diphenyl-1,3-propanedionate) (monophenanthroline) europium (III) (abbreviation: [Eu (DBM) ₃ (Phen)]), tris [1- (2-thenoyl) -3,3, Rare earth metal complexes such as 3-trifluoroacetonato] (monophenanthroline) europium (III) (abbreviation: [Eu (TTA) ₃ (Phen)]).

As the organic compound (host material, assist material) used for the light emitting layer (113, 113a, 113b, 113c), one or more kinds of substances having an energy gap larger than that of the light emitting substance (guest material) are selected. Use it. When a plurality of organic compounds are used for the light-emitting layers (113, 113a, 113b, and 113c), it is preferable to use a compound that forms an exciplex mixed with a phosphorescent material. Note that with such a structure, light emission using ExTET (Exciplex-Triple Energy Transfer), which is energy transfer from the exciplex to the light-emitting substance, can be obtained. In this case, various organic compounds can be used in appropriate combination. However, in order to efficiently form an exciplex, a compound that easily receives holes (hole transporting material) and a compound that easily receives electrons (electrons) A combination with a transportable material) is particularly preferred.

When the light-emitting substance is a fluorescent material, it is preferable to use an organic compound having a large singlet excited state energy level and a small triplet excited state energy level as the host material. For example, it is preferable to use an anthracene derivative or a tetracene derivative. Specifically, 9-phenyl-3- [4- (10-phenyl-9-anthryl) phenyl] -9H-carbazole (abbreviation: PCzPA), 3- [4- (1-naphthyl) -phenyl] -9 -Phenyl-9H-carbazole (abbreviation: PCPN), 9- [4- (10-phenyl-9-anthracenyl) phenyl] -9H-carbazole (abbreviation: CzPA), 7- [4- (10-phenyl-9- Anthryl) phenyl] -7H-dibenzo [c, g] carbazole (abbreviation: cgDBCzPA), 6- [3- (9,10-diphenyl-2-anthryl) phenyl] -benzo [b] naphtho [1,2-d ] Furan (abbreviation: 2 mBnfPPA), 9-phenyl-10- {4- (9-phenyl-9H-fluoren-9-yl) -biphenyl-4'-yl} -anthra Emissions (abbreviation: FLPPA), 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 a triplet excitation energy larger than the triplet excitation energy (energy difference between the ground state and the triplet excited state) of the light-emitting substance may be selected as the host material. In this case, in addition to zinc and aluminum-based metal complexes, oxadiazole derivatives, triazole derivatives, benzimidazole derivatives, quinoxaline derivatives, dibenzoquinoxaline derivatives, dibenzothiophene derivatives, dibenzofuran derivatives, pyrimidine derivatives, triazine derivatives, pyridine derivatives In addition to bipyridine derivatives and phenanthroline derivatives, aromatic amines and carbazole derivatives can be used.

More specifically, for example, the following hole transporting materials and electron transporting materials can be used as the host material.

Examples of these host materials having a high hole transporting property include N, N′-di (p-tolyl) -N, N′-diphenyl-p-phenylenediamine (abbreviation: DTDPPA), 4,4′-bis [ N- (4-diphenylaminophenyl) -N-phenylamino] biphenyl (abbreviation: DPAB), N, N′-bis {4- [bis (3-methylphenyl) amino] phenyl} -N, N′-diphenyl -(1,1′-biphenyl) -4,4′-diamine (abbreviation: DNTPD), 1,3,5-tris [N- (4-diphenylaminophenyl) -N-phenylamino] benzene (abbreviation: DPA3B) An aromatic amine compound such as

In addition, 3- [N- (4-diphenylaminophenyl) -N-phenylamino] -9-phenylcarbazole (abbreviation: PCzDPA1), 3,6-bis [N- (4-diphenylaminophenyl) -N-phenyl Amino] -9-phenylcarbazole (abbreviation: PCzDPA2), 3,6-bis [N- (4-diphenylaminophenyl) -N- (1-naphthyl) amino] -9-phenylcarbazole (abbreviation: PCzTPN2), 3 -[N- (9-phenylcarbazol-3-yl) -N-phenylamino] -9-phenylcarbazole (abbreviation: PCzPCA1), 3,6-bis [N- (9-phenylcarbazol-3-yl)- N-phenylamino] -9-phenylcarbazole (abbreviation: PCzPCA2), 3- [N- (1-naphthyl) -N- (9 Phenyl-3-yl) amino] phenyl carbazole (abbreviation: PCzPCNl) can be mentioned carbazole derivatives such. As other carbazole derivatives, 4,4′-di (N-carbazolyl) biphenyl (abbreviation: CBP), 1,3,5-tris [4- (N-carbazolyl) phenyl] benzene (abbreviation: TCPB) ), 1,4-bis [4- (N-carbazolyl) phenyl] -2,3,5,6-tetraphenylbenzene and the like can also be used.

As a host material having a high hole-transport property, for example, 4,4′-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (abbreviation: NPB or α-NPD), N, N ′ -Bis (3-methylphenyl) -N, N'-diphenyl- [1,1'-biphenyl] -4,4'-diamine (abbreviation: TPD), 4,4 ', 4 "-tris (carbazole- 9-yl) triphenylamine (abbreviation: TCTA), 4,4 ′, 4 ″ -tris [N- (1-naphthyl) -N-phenylamino] triphenylamine (abbreviation: 1′-TNATA), 4 , 4 ′, 4 ″ -tris (N, N-diphenylamino) triphenylamine (abbreviation: TDATA), 4,4 ′, 4 ″ -tris [N- (3-methylphenyl) -N-phenylamino ] Triphenylamine (abbreviation m-MTDATA), 4,4′-bis [N- (spiro-9,9′-bifluoren-2-yl) -N-phenylamino] biphenyl (abbreviation: BSPB), 4-phenyl-4 ′-(9 -Phenylfluoren-9-yl) triphenylamine (abbreviation: BPAFLP), 4-phenyl-3 '-(9-phenylfluoren-9-yl) triphenylamine (abbreviation: mBPAFLP), N- (9,9f- 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 (abbreviation: DFLADFL), N- (9,9-dimethyl-2-diphenylamino-9H-fluoren-7-yl) diphenylamine (abbreviation: DPNF), 2- [N- (4-diphenylaminophenyl) -N-phenylamino] spiro-9,9′-bifluorene (abbreviation: DPASF), 4-phenyl-4 ′-(9-phenyl-9H-carbazole) -3-yl) triphenylamine (abbreviation: PCBA1BP), 4,4′-diphenyl-4 ″-(9-phenyl-9H-carbazol-3-yl) triphenylamine (abbreviation: PCBBi1BP), 4- ( 1-naphthyl) -4 ′-(9-phenyl-9H-carbazol-3-yl) triphenylamine (abbreviation: PCBBANB), 4,4′-di (1-naphthyl) -4 ″-(9-phenyl) -9H-carbazol-3-yl) triphenylamine (abbreviation: PCBNBB), 4-phenyldiphenyl- (9-phenyl-9H-carbazole-3- ) Amine (abbreviation: PCA1BP), N, N′-bis (9-phenylcarbazol-3-yl) -N, N′-diphenylbenzene-1,3-diamine (abbreviation: PCA2B), N, N ′, N ″ -triphenyl-N, N ′, N ″ -tris (9-phenylcarbazol-3-yl) benzene-1,3,5-triamine (abbreviation: PCA3B), N- (4-biphenyl)- N- (9,9-dimethyl-9H-fluoren-2-yl) -9-phenyl-9H-carbazol-3-amine (abbreviation: PCBiF), N- (1,1′-biphenyl-4-yl)- N- [4- (9-phenyl-9H-carbazol-3-yl) phenyl] -9,9-dimethyl-9H-fluoren-2-amine (abbreviation: PCBBiF), 9,9-dimethyl-N-phenyl- N- [ -(9-phenyl-9H-carbazol-3-yl) phenyl] fluoren-2-amine (abbreviation: PCBAF), N-phenyl-N- [4- (9-phenyl-9H-carbazol-3-yl) phenyl ] Spiro-9,9′-bifluoren-2-amine (abbreviation: PCBASF), 2- [N- (9-phenylcarbazol-3-yl) -N-phenylamino] spiro-9,9′-bifluorene (abbreviation) : PCASF), 2,7-bis [N- (4-diphenylaminophenyl) -N-phenylamino] -spiro-9,9'-bifluorene (abbreviation: DPA2SF), N- [4- (9H-carbazole- 9-yl) phenyl] -N- (4-phenyl) phenylaniline (abbreviation: YGA1BP), N, N′-bis [4- (carbazol-9-yl) phenyl An aromatic amine compound such as —N, N′-diphenyl-9,9-dimethylfluorene-2,7-diamine (abbreviation: YGA2F) can be used. 3- [4- (1-naphthyl) -phenyl] -9-phenyl-9H-carbazole (abbreviation: PCPN), 3- [4- (9-phenanthryl) -phenyl] -9-phenyl-9H-carbazole (Abbreviation: PCPPn), 3,3′-bis (9-phenyl-9H-carbazole) (abbreviation: PCCP), 1,3-bis (N-carbazolyl) benzene (abbreviation: mCP), 3,6-bis ( 3,5-diphenylphenyl) -9-phenylcarbazole (abbreviation: CzTP), 4- {3- [3- (9-phenyl-9H-fluoren-9-yl) phenyl] phenyl} dibenzofuran (abbreviation: mmDBFFLBi-II) ), 4,4 ′, 4 ″-(benzene-1,3,5-triyl) tri (dibenzofuran) (abbreviation: DBF3P-II), 1,3,5-tri (di) Nzothiophen-4-yl) -benzene (abbreviation: DBT3P-II), 2,8-diphenyl-4- [4- (9-phenyl-9H-fluoren-9-yl) phenyl] dibenzothiophene (abbreviation: DBTFLP-III) ), 4- [4- (9-phenyl-9H-fluoren-9-yl) phenyl] -6-phenyldibenzothiophene (abbreviation: DBTFLP-IV), 4- [3- (triphenylene-2-yl) phenyl] A carbazole compound such as dibenzothiophene (abbreviation: mDBTPTp-II), a thiophene compound, a furan compound, a fluorene compound, a triphenylene compound, a phenanthrene compound, or the like can be used.

Examples of the host material having a high electron transporting property include tris (8-quinolinolato) aluminum (III) (abbreviation: Alq), tris (4-methyl-8-quinolinolato) aluminum (III) (abbreviation: Almq ₃ ), and bis. (10-hydroxybenzo [h] quinolinato) beryllium (II) (abbreviation: BeBq ₂ ), bis (2-methyl-8-quinolinolato) (4-phenylphenolato) aluminum (III) (abbreviation: BAlq), bis ( Metal complexes having a quinoline skeleton or a benzoquinoline skeleton, such as 8-quinolinolato) zinc (II) (abbreviation: Znq). In addition, bis [2- (2-benzoxazolyl) phenolato] zinc (II) (abbreviation: ZnPBO), bis [2- (2-benzothiazolyl) phenolato] zinc (II) (abbreviation: ZnBTZ), etc. A metal complex having an oxazole-based or thiazole-based ligand can also be used. In addition to metal complexes, 2- (4-biphenylyl) -5- (4-tert-butylphenyl) -1,3,4-oxadiazole (abbreviation: PBD), 1,3-bis [5 -(P-tert-butylphenyl) -1,3,4-oxadiazol-2-yl] benzene (abbreviation: OXD-7), 9- [4- (5-phenyl-1,3,4-oxa) Oxadiazole derivatives such as diazol-2-yl) phenyl] -9H-carbazole (abbreviation: CO11), and 3- (4-biphenylyl) -4-phenyl-5- (4-tert-butylphenyl)- Triazole derivatives such as 1,2,4-triazole (abbreviation: TAZ) and 2,2 ′, 2 ″-(1,3,5-benzenetriyl) tris (1-phenyl-1H-benzimidazole) (Abbreviation: TPBI 2- [3- (dibenzothiophen-4-yl) phenyl] -1-phenyl-1H-benzimidazole (abbreviation: mDBTBIm-II), a compound having an imidazole skeleton (particularly a benzimidazole derivative), Compounds having an oxazole skeleton such as 4′-bis (5-methylbenzoxazol-2-yl) stilbene (abbreviation: BzOs) (particularly benzoxazole derivatives), bathophenanthroline (abbreviation: Bphen), bathocuproin (abbreviation: BCP) Phenanthroline derivatives such as 2,9-bis (naphthalen-2-yl) -4,7-diphenyl-1,10-phenanthroline (abbreviation: NBphen), and 2- [3- (dibenzothiophen-4-yl) phenyl ] Dibenzo [f, h] quinoxaline (abbreviation: 2mDB) PDBq-II), 2- [3 ′-(dibenzothiophen-4-yl) biphenyl-3-yl] dibenzo [f, h] quinoxaline (abbreviation: 2mDBTBPDBq-II), 2- [3 ′-(9H-carbazole) -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- (dibenzothiophene) -4-yl) phenyl] dibenzo [f, h] quinoxaline (abbreviation: 6mDBTPDBq-II), 4,6-bis [ 3- (phenanthrene-9-yl) phenyl] pyrimidine (abbreviation: 4,6mPnP2Pm), 4,6-bis [3- (4-dibenzothienyl) phenyl] pyrimidine (abbreviation: 4,6mDBTP2Pm-II), 4,6 A heterocyclic compound having a diazine skeleton such as -bis [3- (9H-carbazol-9-yl) phenyl] pyrimidine (abbreviation: 4,6mCzP2Pm), 2- {4- [3- (N-phenyl-9H- A heterocyclic compound having a triazine skeleton such as carbazol-3-yl) -9H-carbazol-9-yl] phenyl} -4,6-diphenyl-1,3,5-triazine (abbreviation: PCCzPTzn); -Bis [3- (9H-carbazol-9-yl) phenyl] pyridine (abbreviation: 35DCzPPy), 1,3,5-tri [3- ( - pyridyl) phenyl] benzene (abbreviation: TmPyPB) can also be used a heterocyclic compound having a pyridine skeleton such. In addition, poly (2,5-pyridinediyl) (abbreviation: PPy), poly [(9,9-dihexylfluorene-2,7-diyl) -co- (pyridine-3,5-diyl)] (abbreviation: PF -Py), poly [(9,9-dioctylfluorene-2,7-diyl) -co- (2,2′-bipyridine-6,6′-diyl)] (abbreviation: PF-BPy) Molecular compounds can also be used.

Examples of the host material include condensed polycyclic aromatic compounds such as anthracene derivatives, phenanthrene derivatives, pyrene derivatives, chrysene derivatives, and dibenzo [g, p] chrysene derivatives. Specifically, 9,10-diphenylanthracene ( Abbreviations: DPAnth), N, N-diphenyl-9- [4- (10-phenyl-9-anthryl) phenyl] -9H-carbazol-3-amine (abbreviation: CzA1PA), 4- (10-phenyl-9- Anthryl) triphenylamine (abbreviation: DPhPA), YGAPA, PCAPA, N, 9-diphenyl-N- {4- [4- (10-phenyl-9-anthryl) phenyl] phenyl} -9H-carbazol-3-amine (Abbreviation: PCAPBA), N- (9,10-diphenyl-2-anthryl) -N, 9-di Enyl-9H-carbazol-3-amine (abbreviation: 2PCAPA), 6,12-dimethoxy-5,11-diphenylchrysene, N, N, N ′, N ′, N ″, N ″, N ′ ″ , N ′ ″-octaphenyldibenzo [g, p] chrysene-2,7,10,15-tetraamine (abbreviation: DBC1), 9- [4- (10-phenyl-9-anthracenyl) phenyl] -9H— Carbazole (abbreviation: CzPA), 3,6-diphenyl-9- [4- (10-phenyl-9-anthryl) phenyl] -9H-carbazole (abbreviation: DPCzPA), 9,10-bis (3,5-diphenyl) Phenyl) anthracene (abbreviation: DPPA), 9,10-di (2-naphthyl) anthracene (abbreviation: DNA), 2-tert-butyl-9,10-di (2-naphthyl) Nthracene (abbreviation: t-BuDNA), 9,9′-bianthryl (abbreviation: BANT), 9,9 ′-(stilbene-3,3′-diyl) diphenanthrene (abbreviation: DPNS), 9,9 ′-( Stilbene-4,4′-diyl) diphenanthrene (abbreviation: DPNS2), 1,3,5-tri (1-pyrenyl) benzene (abbreviation: TPB3), or the like can be used.

In the case where a plurality of organic compounds are used for the light-emitting layer (113, 113a, 113b, 113c), two types of compounds (first compound and second compound) that form an exciplex are mixed with an organometallic complex. May be used. In this case, various organic compounds can be used in appropriate combination. However, in order to efficiently form an exciplex, a compound that easily receives holes (hole transporting material) and a compound that easily receives electrons (electrons) A combination with a transportable material) is particularly preferred. Note that as specific examples of the hole-transport material and the electron-transport material, the materials described in this embodiment can be used.

TADF material is a material that can up-convert triplet excited state to singlet excited state with a little thermal energy (interverse crossing) and efficiently emits light (fluorescence) from singlet excited state. is there. As a condition for efficiently obtaining thermally activated delayed fluorescence, the energy difference between the triplet excited level and the singlet excited level is 0 eV or more and 0.2 eV or less, preferably 0 eV or more and 0.1 eV or less. Can be mentioned. In addition, delayed fluorescence in the TADF material refers to light emission having a remarkably long lifetime while having a spectrum similar to that of normal fluorescence. The lifetime is 10 ⁻⁶ seconds or longer, preferably 10 ⁻³ seconds or longer.

Examples of the TADF material include fullerene and derivatives thereof, acridine derivatives such as proflavine, and eosin. In addition, metal-containing porphyrins including magnesium (Mg), zinc (Zn), cadmium (Cd), tin (Sn), platinum (Pt), indium (In), palladium (Pd), and the like can be given. Examples of the metal-containing porphyrin include a protoporphyrin-tin fluoride complex (abbreviation: SnF ₂ (Proto IX)), a mesoporphyrin-tin fluoride complex (abbreviation: SnF ₂ (Meso IX)), and hematoporphyrin-tin fluoride. Complex (abbreviation: SnF ₂ (Hemato IX)), coproporphyrin tetramethyl ester-tin fluoride complex (abbreviation: SnF ₂ (Copro III-4Me)), octaethylporphyrin-tin fluoride complex (abbreviation: SnF ₂ (OEP) )), Etioporphyrin-tin fluoride complex (abbreviation: SnF ₂ (Etio I)), octaethylporphyrin-platinum chloride complex (abbreviation: PtCl ₂ OEP), and the like.

In addition, 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 -Acridine- 0-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., a heterocyclic ring having a π-electron rich heteroaromatic ring and a π-electron deficient heteroaromatic ring Compounds can be used. In addition, a substance in which a π-electron rich heteroaromatic ring and a π-electron deficient heteroaromatic ring are directly bonded increases both the donor property of the π-electron rich heteroaromatic ring and the acceptor property of the π-electron deficient heteroaromatic ring. This is particularly preferable because the energy difference between the singlet excited state and the triplet excited state becomes small.

In addition, when using TADF material, it can also be used in combination with another organic compound.

In the light emitting element shown in FIG. 1, the electron transport layer (114, 114a) is formed on the light emitting layer (113, 113a) of the EL layer (103, 103a) by a vacuum deposition method. Note that in the case of the light-emitting element having a tandem structure illustrated in FIG. 1D, after the EL layer 103a and the charge generation layer 104 are formed, the electron transport layer 114b is vacuum-deposited on the light-emitting layer 113b of the EL layer 103b. Formed by law.

<Electron transport layer>
The electron transport layer (114, 114a, 114b) is a layer that transports electrons injected from the second electrode 102 to the light emitting layer (113, 113a, 113b) by the electron injection layer (115, 115a, 115b). . Note that the electron transport layers (114, 114a, 114b) are layers containing an electron transport material. The electron transporting material used for the electron transporting layer (114, 114a, 114b) is preferably a substance having an electron mobility of 1 × 10 ⁻⁶ cm ² / Vs or higher. Note that other than these substances, any substance that has a property of transporting more electrons than holes can be used.

Examples of electron transporting materials include metal complexes having quinoline ligand, benzoquinoline ligand, oxazole ligand, or thiazole ligand, oxadiazole derivatives, triazole derivatives, phenanthroline derivatives, pyridine derivatives, bipyridine derivatives, etc. Is mentioned. In addition, a π-electron deficient heteroaromatic compound such as a nitrogen-containing heteroaromatic compound can also be used.

Specifically, Alq ₃ , tris (4-methyl-8-quinolinolato) aluminum (abbreviation: Almq ₃ ), bis (10-hydroxybenzo [h] quinolinato) beryllium (abbreviation: BeBq ₂ ), BAlq, bis [2 -(2-hydroxyphenyl) benzoxazolate] zinc (II) (abbreviation: Zn (BOX) ₂ ), bis [2- (2-hydroxyphenyl) benzothiazolate] zinc (abbreviation: Zn (BTZ) ₂ ), etc. Metal complex, 2- (4-biphenylyl) -5- (4-tert-butylphenyl) -1,3,4-oxadiazole (abbreviation: PBD), OXD-7, 3- (4′-tert-butyl) Phenyl) -4-phenyl-5- (4 ''-biphenylyl) -1,2,4-triazole (abbreviation: TAZ), 3- (4-tert-butylphenyl)- 4- (4-ethylphenyl) -5- (4-biphenylyl) -1,2,4-triazole (abbreviation: p-EtTAZ), bathophenanthroline (abbreviation: Bphen), bathocuproin (abbreviation: BCP), 4,4 Heteroaromatic compounds such as' -bis (5-methylbenzoxazol-2-yl) stilbene (abbreviation: BzOs), 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- [4- (3 6-diphenyl-9H-carbazol-9-yl) phenyl] dibenzo [f, h] quinoxaline (abbreviation: 2CzPDBq-I) I), 7- [3- (dibenzothiophen-4-yl) phenyl] dibenzo [f, h] quinoxaline (abbreviation: 7mDBTPDBq-II), 6- [3- (dibenzothiophen-4-yl) phenyl] dibenzo [ f, h] quinoxaline or dibenzoquinoxaline derivatives such as quinoxaline (abbreviation: 6mDBTPDBq-II) can be used.

In addition, poly (2,5-pyridinediyl) (abbreviation: PPy), poly [(9,9-dihexylfluorene-2,7-diyl) -co- (pyridine-3,5-diyl)] (abbreviation: PF -Py), poly [(9,9-dioctylfluorene-2,7-diyl) -co- (2,2′-bipyridine-6,6′-diyl)] (abbreviation: PF-BPy) Molecular compounds can also be used.

Further, the electron-transport layer (114, 114a, 114b) is not limited to a single layer, and may have a structure in which two or more layers made of the above substances are stacked.

In the light emitting element shown in FIG. 1, the electron injection layer (114, 114a) is formed on the electron transport layer (114, 114a) of the EL layer (103, 103a) by a vacuum deposition method. Note that in the case of the light-emitting element having a tandem structure illustrated in FIG. 1D, after the EL layer 103a and the charge generation layer 104 are formed, the electron-injection layer 114b is also formed on the electron-transport layer 114b of the EL layer 103b. It is formed by a vapor deposition method.

<Electron injection layer>
The electron injection layers (115, 115a, 115b) are layers containing a substance having a high electron injection property. The electron injection layer (115, 115a, 115b) includes an alkali metal such as lithium fluoride (LiF), cesium fluoride (CsF), calcium fluoride (CaF ₂ ), lithium oxide (LiO _x ), or the like. Earth metals or their compounds can be used. Alternatively, a rare earth metal compound such as erbium fluoride (ErF ₃ ) can be used. Further, electride may be used for the electron injection layer (115, 115a, 115b). Examples of the electride include a substance obtained by adding a high concentration of electrons to a mixed oxide of calcium and aluminum. In addition, the substance which comprises the electron carrying layer (114, 114a, 114b) mentioned above can also be used.

Alternatively, a composite material obtained by mixing an organic compound and an electron donor (donor) may be used for the electron injection layer (115, 115a, 115b). Such a composite material is excellent in electron injecting property and electron transporting property because electrons are generated in the organic compound by the electron donor. In this case, the organic compound is preferably a material excellent in transporting the generated electrons. Specifically, for example, an electron transport material (metal complex) used for the electron transport layer (114, 114a, 114b) described above, for example. Or a heteroaromatic compound). The electron donor may be any substance that exhibits an electron donating property to the organic compound. Specifically, alkali metals, alkaline earth metals, and rare earth metals are preferable, and lithium, cesium, magnesium, calcium, erbium, ytterbium, and the like can be given. Alkali metal oxides and alkaline earth metal oxides are preferable, and lithium oxide, calcium oxide, barium oxide, and the like can be given. A Lewis base such as magnesium oxide can also be used. Alternatively, an organic compound such as tetrathiafulvalene (abbreviation: TTF) can be used.

For example, in the case of amplifying light obtained from the light-emitting layer 113b, the optical distance between the second electrode 102 and the light-emitting layer 103b is less than λ / 4 with respect to the wavelength of light exhibited by the light-emitting layer 103b. It is preferable to form such that In this case, adjustment can be performed by changing the film thickness of the electron transport layer 114b or the electron injection layer 115b.

<Charge generation layer>
The charge generation layer 104 injects electrons into the EL layer 103a and applies holes into the EL layer 103b when a voltage is applied between the first electrode (anode) 101 and the second electrode (cathode) 102. Has the function of injecting. Note that the charge generation layer 104 may have a structure in which an electron acceptor is added to a hole transporting material or a structure in which an electron donor (donor) is added to an electron transporting material. Good. Moreover, both these structures may be laminated | stacked. Note that by forming the charge generation layer 104 using the above-described material, an increase in driving voltage in the case where an EL layer is stacked can be suppressed.

In the case where 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 can be used as the hole-transporting material. Examples of the electron acceptor include 7,7,8,8-tetracyano-2,3,5,6-tetrafluoroquinodimethane (abbreviation: F ₄ -TCNQ), chloranil, and the like. In addition, oxides of metals belonging to Groups 4 to 8 in the periodic table can be given. Specific examples 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 can be used as the electron transporting material. As the electron donor, an alkali metal, an alkaline earth metal, a rare earth metal, a metal belonging to Groups 2 and 13 of the periodic table, or an oxide or carbonate thereof can be used. Specifically, lithium (Li), cesium (Cs), magnesium (Mg), calcium (Ca), ytterbium (Yb), indium (In), lithium oxide, cesium carbonate, or the like is preferably used. An organic compound such as tetrathianaphthacene may be used as an electron donor.

Note that the EL layer 103c in FIG. 1E may have a structure similar to that of the above-described EL layers (103, 103a, and 103b). In addition, the intermediate layers 104a and 104b may have the same structure as the intermediate layer 104 described above.

<Board>
The light-emitting element described in this embodiment can be formed over various substrates. In addition, the kind of board | substrate is not limited to a specific thing. As an example of the substrate, a semiconductor substrate (for example, 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 having stainless steel foil, a tungsten substrate, Examples include a substrate having a tungsten foil, a flexible substrate, a laminated film, a paper containing a fibrous material, or a base film.

Note that examples of the glass substrate include barium borosilicate glass, aluminoborosilicate glass, and soda lime glass. Moreover, as an example of a flexible substrate, a laminated film, a base film, etc., plastics such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polyethersulfone (PES), acrylic resin, etc. Synthetic resin, polypropylene, polyester, polyvinyl fluoride, or polyvinyl chloride, polyamide, polyimide, aramid, epoxy, inorganic vapor deposition film, paper, and the like can be given.

Note that for manufacturing the light-emitting element described in this embodiment, a vacuum process such as an evaporation method or a solution process such as a spin coating method or an inkjet method can be used. When vapor deposition is used, physical vapor deposition (PVD) such as sputtering, ion plating, ion beam vapor deposition, molecular beam vapor deposition, or vacuum vapor deposition, or chemical vapor deposition (CVD) is used. be able to. In particular, functional layers (hole injection layer (111, 111a, 111b), hole transport layer (112, 112a, 112b), light-emitting layer (113, 113a, 113b, 113c), electron transport included in the EL layer of the light-emitting element. For the layers (114, 114a, 114b), the electron injection layer (115, 115a, 115b), and the charge generation layer (104, 104a, 104b)), a vapor deposition method (vacuum vapor deposition method, etc.), a coating method (dip coating method) , Die coating method, bar coating method, spin coating method, spray coating method, etc.), printing method (inkjet method, screen (stencil printing) method, offset (lithographic printing) method, flexographic (letter printing) method, gravure method, microcontact And the like.

Note that each functional layer (a hole injection layer (111, 111a, 111b), a hole transport layer (112, 112a, 112b) included in the EL layer (103, 103a, 103b) of the light-emitting element described in this embodiment mode. 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)) are described above. The material is not limited, and other materials can be used in combination as long as they can satisfy the function of each layer. For example, a high molecular compound (oligomer, dendrimer, polymer, etc.), a medium molecular compound (compound in the middle region between a low molecule and a high molecule: molecular weight 400 to 4000), an inorganic compound (quantum dot material, etc.), etc. are used. it can. As the quantum dot material, a colloidal quantum dot material, an alloy type quantum dot material, a 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 combined as appropriate with any of the structures described in the other embodiments.

(Embodiment 3)
In this embodiment, a light-emitting device will be described. 2A is an active matrix light-emitting device in which a transistor (FET) 202 over a first substrate 201 and light-emitting elements (203R, 203G, 203B, and 203W) are electrically connected to each other. The plurality of light emitting elements (203R, 203G, 203B, 203W) have a common EL layer 204, and the optical distance between the electrodes of each light emitting element depends on the emission color of each light emitting element. It has a tuned microcavity structure. In addition, the light-emitting device is a top-emission light-emitting device in which light emission obtained from the EL layer 204 is emitted through color filters (206R, 206G, and 206B) formed over the second substrate 205.

In the light-emitting device illustrated in FIG. 2A, the first electrode 207 is formed so as to function as a reflective electrode. Further, the second electrode 208 is formed so as to function as a semi-transmissive / semi-reflective electrode. Note that an electrode material for forming the first electrode 207 and the second electrode 208 may be used as appropriate with reference to the description of the other embodiments.

In FIG. 2A, for example, when the light emitting element 203R is a red light emitting element, the light emitting element 203G is a green light emitting element, the light emitting element 203B is a blue light emitting element, and the light emitting element 203W is a white light emitting element, FIG. ), The light emitting element 203R is adjusted so that the optical distance 200R is between the first electrode 207 and the second electrode 208, and the light emitting element 203G includes the first electrode 207 and the second electrode. The light emitting element 203B is adjusted so that the optical distance 200B is between the first electrode 207 and the second electrode 208. Note that as illustrated in FIG. 2B, optical adjustment can be performed by stacking the conductive layer 210R over the first electrode 207 in the light-emitting element 203R and stacking the conductive layer 210G in the light-emitting element 203G.

On the second substrate 205, color filters (206R, 206G, 206B) are formed. The color filter is a filter that passes a specific wavelength range of visible light and blocks the specific wavelength range. Therefore, as shown in FIG. 2A, red light emission can be obtained from the light emitting element 203R by providing the color filter 206R that allows only the red wavelength region to pass through the position overlapping the light emitting element 203R. In addition, by providing the color filter 206G that allows only the green wavelength region to pass at a position overlapping the light emitting element 203G, green light emission can be obtained from the light emitting element 203G. Further, by providing the color filter 206B that allows only the blue wavelength region to pass at a position overlapping the light emitting element 203B, blue light emission can be obtained from the light emitting element 203B. However, the light emitting element 203W can obtain white light emission without providing a color filter. Note that a black layer (black matrix) 209 may be provided at an end of one type of color filter. Further, the color filters (206R, 206G, 206B) and the black layer 209 may be covered with an overcoat layer using a transparent material.

In FIG. 2A, a light emitting device having a structure for extracting light emission to the second substrate 205 side (top emission type) is shown, but the first substrate on which the FET 202 is formed as shown in FIG. A light emitting device having a structure for extracting light to the 201 side (bottom emission type) may be used. Note that in the case of a bottom emission type light-emitting device, the first electrode 207 is formed to function as a semi-transmissive / semi-reflective electrode, and the second electrode 208 is formed to function as a reflective electrode. The first substrate 201 is at least a light-transmitting substrate. Further, the color filters (206R ′, 206G ′, and 206B ′) may be provided on the first substrate 201 side with respect to the light emitting elements (203R, 203G, and 203B) as shown in FIG.

2A illustrates the case where the light-emitting element is a red light-emitting element, a green light-emitting element, a blue light-emitting element, or a white light-emitting element, the structure is not limited thereto, and a yellow light-emitting element or an orange light-emitting element is used. The structure which has this light emitting element may be sufficient. In addition, as a material used for EL layers (a light emitting layer, a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, a charge generation layer, etc.) for manufacturing these light emitting elements, other embodiments are used. May be used as appropriate with reference to the description. In this case, it is necessary to select a color filter as appropriate in accordance with the emission color of the light emitting element.

With the above structure, a light-emitting device including a light-emitting element that exhibits a plurality of emission colors can be obtained.

Note that the structure described in this embodiment can be combined as appropriate with any of the structures described in the other embodiments.

(Embodiment 4)
In this embodiment, a light-emitting device will be described.

By applying the element structure of the light-emitting element described in the other embodiments, an active matrix light-emitting device or a passive matrix light-emitting device can be manufactured. Note that an active matrix light-emitting device has a structure in which a light-emitting element and a transistor (FET) are combined.

In this embodiment, an active matrix light-emitting device is described with reference to FIGS.

3A is a top view showing the light-emitting device 21, and FIG. 3B is a cross-sectional view taken along the chain line A-A 'in FIG. 3A. The active matrix light-emitting device includes a pixel portion 302, a driver circuit portion (source line driver circuit) 303, and driver circuit portions (gate line driver circuits) (304a and 304b) provided over the first substrate 301. . The pixel portion 302 and the driver circuit portions (303, 304a, and 304b) are sealed between the first substrate 301 and the second substrate 306 by a sealant 305.

A lead wiring 307 is provided over the first substrate 301. The lead wiring 307 is electrically connected to the FPC 308 which is an external input terminal. Note that the FPC 308 transmits signals (eg, a video signal, a clock signal, a start signal, a reset signal, and the like) and a potential from the outside to the driving circuit units (303, 304a, and 304b). Further, a printed wiring board (PWB) may be attached to the FPC 308. Note that the state in which the FPC or PWB is attached is included in the light emitting device.

Next, a cross-sectional structure is shown in FIG.

The pixel portion 302 is formed by a plurality of pixels including a FET (switching FET) 311, a FET (current control FET) 312, and a first electrode 313 electrically connected to the FET 312. Note that the number of FETs included in each pixel is not particularly limited, and can be appropriately provided as necessary.

The FETs 309, 310, 311, and 312 are not particularly limited, and for example, a staggered type transistor or an inverted staggered type transistor can be applied. Further, a transistor structure such as a top gate type or a bottom gate type may be used.

Note that there is no particular limitation on the crystallinity of the semiconductor that can be used for these FETs 309, 310, 311, and 312; an amorphous semiconductor, a semiconductor having crystallinity (a microcrystalline semiconductor, a polycrystalline semiconductor, a single crystal semiconductor, Alternatively, a semiconductor having a crystal region in part) may be used. Note that it is preferable to use a crystalline semiconductor because deterioration of transistor characteristics can be suppressed.

As these semiconductors, for example, Group 14 elements, compound semiconductors, oxide semiconductors, organic semiconductors, and 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 drive circuit unit 303 includes an FET 309 and an FET 310. Note that the FET 309 and the FET 310 may be formed of a circuit including a unipolar transistor (N-type or P-type only) or a CMOS circuit including an N-type transistor and a P-type transistor. May be. In addition, a configuration in which a drive circuit is provided outside may be employed.

An end portion of the first electrode 313 is covered with an insulator 314. Note that the insulator 314 can be formed using 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. . It is preferable that an upper end portion or a lower end portion of the insulator 314 have a curved surface having a curvature. Thereby, the coverage of the film formed on the upper layer of the insulator 314 can be improved.

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 injection layer, a hole transport layer, an electron transport layer, an electron injection layer, a charge generation layer, and the like.

Note that the structures and materials described in the other embodiments can be applied to the structure of the light-emitting element 317 described in this embodiment. Although not shown here, the second electrode 316 is electrically connected to the FPC 308 which is an external input terminal.

3B illustrates only one light-emitting element 317, it is assumed that a plurality of light-emitting elements are arranged in a matrix in the pixel portion 302. In the pixel portion 302, light emitting elements capable of emitting three types (R, G, and B) of light emission can be selectively formed, so that a light emitting device capable of full color display can be formed. In addition to the light emitting element that can obtain three types of light emission (R, G, B), for example, light emission that can emit light such as white (W), yellow (Y), magenta (M), and cyan (C). An element may be formed. For example, by adding the above-described light emitting elements capable of obtaining several types of light emission (R, G, B) to the light emitting elements capable of obtaining three types of light emission (R, G, B), effects such as improvement in color purity and reduction in power consumption can be obtained. Can do. Alternatively, a light emitting device capable of full color display may be obtained by combining with a color filter. Note that as types of color filters, red (R), green (G), blue (B), cyan (C), magenta (M), yellow (Y), and the like can be used.

The FETs (309, 310, 311 and 312) and the light emitting element 317 over the first substrate 301 are bonded to each other by attaching the second substrate 306 and the first substrate 301 with the sealant 305. 301, the second substrate 306, and a structure provided in a space 318 surrounded by the sealant 305. Note that the space 318 may be filled with an inert gas (such as nitrogen or argon) or an organic substance (including the sealant 305).

As the sealant 305, an epoxy resin or glass frit can be used. Note that it is preferable to use a material that does not transmit moisture and oxygen as much as possible for the sealant 305. In addition, as the second substrate 306, a substrate that can be used for the first substrate 301 can be used as well. Therefore, various substrates described in other embodiments can be used as appropriate. In addition to a glass substrate or a quartz substrate, a plastic substrate made of FRP (Fiber-Reinforced Plastics), PVF (polyvinyl fluoride), polyester, acrylic resin, or the like can be used as the substrate. In the case where glass frit is used as the sealing material, the first substrate 301 and the second substrate 306 are preferably glass substrates from the viewpoint of adhesiveness.

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

In the case where an active matrix light-emitting device is formed over a flexible substrate, the FET and the light-emitting element may be directly formed over the flexible substrate, but the FET and the light-emitting element are formed over another substrate having a release layer. After forming, the FET and the light-emitting element may be peeled off by a peeling layer by applying heat, force, laser irradiation, and transferred to a flexible substrate. Note that as the peeling layer, for example, a laminated inorganic film of a tungsten film and a silicon oxide film, an organic resin film such as polyimide, or the like can be used. In addition to substrates that can form transistors, flexible substrates include paper substrates, cellophane substrates, aramid film substrates, polyimide film substrates, fabric substrates (natural fibers (silk, cotton, hemp), synthetic fibers ( Nylon, polyurethane, polyester) or recycled fibers (including acetate, cupra, rayon, recycled polyester), leather substrates, rubber substrates, and the like. By using these substrates, it is excellent in durability and heat resistance, and can be reduced in weight and thickness.

Note that the structure described in this embodiment can be combined with any of the structures described in other embodiments as appropriate.

(Embodiment 5)
In this embodiment, examples of various electronic devices and automobiles completed by applying a light-emitting device, a display device, and the like will be described.

An electronic device illustrated in FIGS. 4A to 4E includes 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), a connection terminal 7006, Sensor 7007 (force, displacement, position, velocity, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemical substance, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity , Including a function of measuring inclination, vibration, odor, or infrared light), a microphone 7008, and the like.

FIG. 4A illustrates a mobile computer, which can include a switch 7009, an infrared port 7010, and the like in addition to the above objects.

FIG. 4B illustrates a portable image reproducing device (eg, a DVD reproducing device) provided with a recording medium, which includes a second display portion 7002, a recording medium reading portion 7011, and the like in addition to those described above. it can.

FIG. 4C illustrates a goggle type display which can include a second display portion 7002, a support portion 7012, an earphone 7013, and the like in addition to the above components.

FIG. 4D illustrates a digital camera with 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 objects.

FIG. 4E illustrates a mobile phone (including a smartphone), which can include a display portion 7001, a microphone 7008, a speaker 7003, a camera 7020, an external connection portion 7021, an operation button 7022, and the like in a housing 7000. .

FIG. 4F illustrates a large television device (also referred to as a television or a television receiver) which can include a housing 7000, a display portion 7001, and the like. Here, a configuration in which the casing 7000 is supported by a stand 7018 is shown. The television device can be operated by a separate remote controller 7111 or the like. Note that the display portion 7001 may be provided with a touch sensor, and may be operated by touching the display portion 7001 with a finger or the like. The remote controller 7111 may include a display unit that displays information output from the remote controller 7111. Channels and volume can be operated with an operation key or a touch panel included in the remote controller 7111, and an image displayed on the display portion 7001 can be operated.

The electronic devices illustrated in FIGS. 4A to 4F can have a variety of functions. For example, a function for displaying various information (still images, moving images, text images, etc.) on the display unit, a touch panel function, a function for displaying a calendar, date or time, etc., a function for controlling processing by various software (programs) , Wireless communication function, function to connect to various computer networks using wireless communication function, function to transmit or receive various data using wireless communication function, read program or data recorded in recording medium A function of displaying on the display portion can be provided. Further, in an electronic device having a plurality of display units, one display unit mainly displays image information and another one display unit mainly displays character information, or the plurality of display units consider parallax. It is possible to have a function of displaying a three-dimensional image, etc. by displaying the obtained image. Furthermore, in an electronic device having an image receiving unit, a function for capturing a still image, a function for capturing a moving image, a function for correcting a captured image automatically or manually, and a captured image on a recording medium (externally or incorporated in a camera) A function of saving, a function of displaying a photographed image on a display portion, and the like can be provided. Note that the functions of the electronic devices illustrated in FIGS. 4A to 4F are not limited to these, and the electronic devices can have various functions.

FIG. 4G illustrates a smart watch, which includes a housing 7000, a display portion 7001, operation buttons 7022 and 7023, a connection terminal 7024, a band 7025, a clasp 7026, and the like.

A display portion 7001 mounted on a housing 7000 that also serves as a bezel portion has a non-rectangular display region. The display portion 7001 can display an icon 7027 representing time, other icons 7028, and the like. The display unit 7001 may be a touch panel (input / output device) equipped with a touch sensor (input device).

Note that the smart watch illustrated in FIG. 4G can have a variety of functions. For example, a function for displaying various information (still images, moving images, text images, etc.) on the display unit, a touch panel function, a function for displaying a calendar, date or time, etc., a function for controlling processing by various software (programs) , Wireless communication function, function to connect to various computer networks using wireless communication function, function to transmit or receive various data using wireless communication function, read program or data recorded in recording medium A function of displaying on the display portion can be provided.

In addition, a speaker, a sensor (force, displacement, position, velocity, acceleration, angular velocity, number of rotations, distance, light, liquid, magnetism, temperature, chemical substance, sound, time, hardness, electric field, current are included in the housing 7000. , Voltage, power, radiation, flow rate, humidity, gradient, vibration, odor or infrared measurement function), microphone, and the like.

In addition, as an electronic device to which the light-emitting device is applied, a foldable portable information terminal as illustrated in FIGS. FIG. 5A illustrates the portable information terminal 9310 in a developed state. FIG. 5B illustrates the portable information terminal 9310 in a state of changing from one of the expanded state and the folded state to the other. Further, FIG. 5C illustrates the portable information terminal 9310 in a folded state. The portable information terminal 9310 is excellent in portability in the folded state and excellent in display listability due to a seamless wide display area in the expanded state.

The display portion 9311 is supported by three housings 9315 connected by a hinge 9313. Note that the display unit 9311 may be a touch panel (input / output device) equipped with a touch sensor (input device). In addition, the display portion 9311 can be reversibly deformed from the expanded state to the folded state by bending the two housings 9315 via the hinge 9313. Note that a light-emitting device can be used for the display portion 9311. A display region 9312 in the display portion 9311 is a display region located on a side surface of the portable information terminal 9310 in a folded state. In the display area 9312, information icons, frequently used applications, program shortcuts, and the like can be displayed, so that information can be confirmed and applications can be activated smoothly.

FIGS. 6A and 6B illustrate an automobile to which the light-emitting device is applied. That is, the light emitting device can be provided integrally with the automobile. Specifically, the present invention can be applied to a light 5101 (including a rear part of a vehicle body), a wheel 5102 of a tire, a part of or the whole of a door 5103 shown in FIG. Further, the present invention can be applied to a display portion 5104, a handle 5105, a shift lever 5106, a seat seat 5107, an inner rear view mirror 5108, and the like inside the automobile shown in FIG. In addition, you may apply to some glass windows.

As described above, an electronic device or an automobile to which the light-emitting device or the display device is applied can be obtained. Note that applicable electronic devices and automobiles are not limited to those described in this embodiment, and can be applied in any field.

Note that the structure described in this embodiment can be combined as appropriate with any of the structures described in the other embodiments.

(Embodiment 6)
In this embodiment, a structure of a lighting device manufactured using a light-emitting device or the like will be described with reference to FIGS.

7A and 7B illustrate examples of cross-sectional views of the lighting device. Note that FIG. 7A illustrates a bottom emission type illumination device that extracts light to the substrate side, and FIG. 7B illustrates a top emission type illumination device that extracts light to the sealing substrate side.

A lighting device 4000 illustrated in FIG. 7A includes a light-emitting element 4002 over a substrate 4001. In addition, a substrate 4003 having unevenness is provided outside the substrate 4001. The light-emitting element 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. Further, an auxiliary wiring 4009 that is electrically connected to the first electrode 4004 may be provided. Note that an insulating layer 4010 is formed over the auxiliary wiring 4009.

In addition, the substrate 4001 and the sealing substrate 4011 are bonded with a sealant 4012. In addition, a desiccant 4013 is preferably provided between the sealing substrate 4011 and the light-emitting element 4002. Note that since the substrate 4003 has unevenness as illustrated in FIG. 7A, the light extraction efficiency of the light-emitting element 4002 can be improved.

A lighting device 4200 in FIG. 7B includes a light-emitting element 4202 over a substrate 4201. The light-emitting element 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. Further, an auxiliary wiring 4209 that is electrically connected to the second electrode 4206 may be provided. Further, an insulating layer 4210 may be provided below the auxiliary wiring 4209.

The substrate 4201 and the uneven sealing substrate 4211 are bonded with 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 element 4202. Note that the sealing substrate 4211 has unevenness as illustrated in FIG. 7B; thus, extraction efficiency of light generated in the light-emitting element 4202 can be improved.

Moreover, as an application example of these lighting devices, a ceiling light for indoor lighting can be cited. Ceiling lights include a direct ceiling type and a ceiling embedded type. Note that such an illumination device is configured by combining a light emitting device with a housing or a cover.

In addition, it can be applied to a foot lamp that can illuminate the floor surface and enhance the safety of the foot. For example, the foot lamp is effective for use in a bedroom, a staircase, a passage, or the like. In that case, the size and shape can be appropriately changed according to the size and structure of the room. In addition, a stationary illumination device configured by combining a light emitting device and a support base can be provided.

Moreover, it is also possible to apply as a sheet-like illumination device (sheet-like illumination). Since the sheet-like illumination is used by being attached to the wall surface, it can be used for a wide range of applications without taking up space. It is easy to increase the area. In addition, it can also be used for the wall surface and housing | casing which have a curved surface.

In addition to the above, a lighting device or the like can be applied to part of furniture provided in the room, whereby a lighting device having a function as furniture can be obtained.

As described above, various lighting devices to which the light-emitting device is applied can be obtained.

The structure described in this embodiment can be combined as appropriate with any of the structures described in the other embodiments.

In this example, as an example of a method for synthesizing an organic compound having a condensed carbazole skeleton which is one embodiment of the present invention, 7- [4- (10-phenyl-9-] represented by the following structural formula (100) is used. An anthryl) phenyl] -7H-dibenzo [c, g] carbazole (abbreviation: cgDBCzPA) synthesis method is described. The structure of cgDBCzPA is shown below.

<Step 1: Synthesis of 6,7,8,9-tetrahydro-5H-dibenzo [c, g] carbazole>
In a 5 L three-necked flask, 800 g (5.5 mol) of β-tetralone, 152 mL (2.5 mol 79%) of hydrazine monohydrate, 29 g (0.13 mol) of dibutylhydroxytoluene (BHT), and ethanol (EtOH) 2 0.7 L and acetic acid (AcOH) 6.3 mL (54 mmol) were added. The mixture was degassed by stirring it under reduced pressure, and the atmosphere in the flask was replaced with nitrogen after degassing.

Next, the mixture was stirred overnight at room temperature under a nitrogen stream, and then stirred at 85 ° C. for 15.5 hours. The mixture was cooled to about 0 ° C. in an ice bath, and the solid was separated by suction filtration to obtain the target red solid in a yield of 588 g and a yield of 88%.

1393 g of the target red solid obtained by repeating the same process as described above a plurality of times was placed in a 50 L reaction vessel, and 15.4 L of toluene was added. The mixture was degassed by stirring it under reduced pressure, and after degassing, the inside of the container was purged with nitrogen. The mixture was stirred while heating to reflux to dissolve the solid, and then cooled to about 60 ° C. The resulting mixture was concentrated and stirred while cooling to about 0 ° C. in an ice bath, and then the powder was separated by suction filtration to obtain the desired pale purple powder in a yield of 1153 g and a yield of 72%. A synthesis scheme (a-1) of Step 1 is shown below.

Note that the compound obtained in Step 1 above was converted into the target product shown in Synthesis Scheme (a-1), 6,7,8,9-tetrahydro-5H-dibenzo [c, g by nuclear magnetic resonance (NMR). It was confirmed to be carbazole.

Next, a method for synthesizing 7H-dibenzo [c, g] carbazole using 6,7,8,9-tetrahydro-5H-dibenzo [c, g] carbazole synthesized in Step 1 is described in Step 2 (Step 2). -1, step 2-2). Step 2-1 shows the case where an oxidizing agent containing chlorine as an oxidizing agent (chloranil: tetrachloro-1,4-benzoquinone) is used, and step 2-2 shows an oxidizing not containing chlorine as an oxidizing agent. The case where an agent (1,4 benzoquinone) is used will be described.

<Step 2-1: Synthesis of 7H-dibenzo [c, g] carbazole using chloranil (tetrachloro-1,4-benzoquinone)>
In a 50 L reaction vessel, 570 g (2.1 mol) of 6,7,8,9-tetrahydro-5H-dibenzo [c, g] carbazole obtained in Step 1 above, 1033 g (4.2 mol) of chloranil, and dibutyl 4.6 g (0.21 mol) of hydroxytoluene (BHT) was added and 10.5 L of xylene was added. The mixture was stirred and degassed under reduced pressure, and then the atmosphere in the container was replaced with nitrogen. The mixture was stirred at 40 ° C. for 4.5 hours and 130 ° C. for 4.5 hours.

While this mixture was heated to 60 ° C., it was washed twice with 12.5 L of a 1 mol / L aqueous sodium hydroxide solution, once with 4.5 L of a saturated aqueous sodium bicarbonate solution, and once with 4.5 L of a saturated saline solution. . After washing, the organic layer in the mixture was concentrated to about 3 L, and 5 L of toluene was added thereto and concentrated. Next, 5 L of toluene is added to this mixture and heated to 60 ° C. to dissolve all solids to form a solution. This solution is purified using Celite (Wako Pure Chemical Industries, Ltd., catalog number: 531-16855) and alumina. did.

After concentrating the yellow solution obtained by purification, 5 L of toluene was added, and the mixture was washed twice with 12.5 L of a 1 mol / L sodium hydroxide aqueous solution while heating to 60 ° C. Then, this solution was concentrated and recrystallized using ethanol and hexane to obtain a target light purple solid in a yield of 507 g and a yield of 90%.

505 g of the obtained light purple solid was purified by sublimation by the train sublimation method. The sublimation purification was performed by heating the light purple solid at 215 ° C. under the conditions of a pressure of 0.88 Pa and an argon flow rate of 100 mL / min. After purification by sublimation, a target white solid was obtained in a yield of 468 g and a recovery rate of 93%. A synthesis scheme (a-2-1) of Step 2-1 is shown below.

The ¹ H NMR data of the obtained white solid is shown below. ¹ H NMR (CDCl ₃ , 500 MHz): δ = 7.53 (t, J = 7.5 Hz, 2H), 7.66 (d, J = 8.6 Hz, 2H), 7.70 (ddd, J = 7.5, 7, 5, 1.2 Hz, 2H), 7.87 (d, J = 9.1 Hz, 2H), 8.05 (d, J = 8.0 Hz, 2H), 8.71 (s) 1H), 9.23 (d, J = 8.6 Hz, 2H).

Further, the ¹ H NMR chart is shown in FIG. From the measurement results, it was confirmed that the compound obtained in Step 2-1 was the target product shown in Synthesis Scheme (a-2-1), 7H-dibenzo [c, g] carbazole.

Here, the purity analysis of the obtained 7H-dibenzo [c, g] carbazole was performed by ACQUITY Ultra Performance LC (hereinafter, UPLC) manufactured by Waters. As a result, a substance having a mass-to-charge ratio (m / z) = 371 as an impurity other than 7H-dibenzo [c, g] carbazole was detected in an area ratio of 0.1%, and the purity was calculated to be 99.9%. . Further, as another impurity whose area ratio is less than 0.1%, a substance having a mass-to-charge ratio (m / z) = 301 was included. Note that a substance having a mass to charge ratio (m / z) = 301 is a monochlorinated 7H-dibenzo [c, 7H-dibenzo [c, g] carbazole in which any one hydrogen atom is substituted with a chlorine atom. g] It can be estimated as carbazole. In addition, the obtained MS spectrum is shown in FIG.

Next, in order to accurately confirm these impurities contained in 7H-dibenzo [c, g] carbazole, measurement was performed using combustion ion chromatography. As a result, it was found that the content of chlorine in 7H-dibenzo [c, g] carbazole was 11 ppm.

Therefore, chlorine contained in 7H-dibenzo [c, g] carbazole was further analyzed by gas chromatography. As a result, the chlorine detected by combustion ion chromatography was not the chloranil used as the oxidizing agent in the reaction shown in the synthesis scheme (a-2-1), but the 7H-dibenzo [c, g] carbazole as the raw material. It was presumed to be derived from a monochlorine-substituted 7H-dibenzo [c, g] carbazole in which any one hydrogen atom was substituted with a chlorine atom.

<Step 2-2: Synthesis of 7H-dibenzo [c, g] carbazole using benzoquinone>
In a 50 L reaction vessel, 570 g (2.1 mol) of 6,7,8,9-tetrahydro-5H-dibenzo [c, g] carbazole obtained in Step 1 above and 908 g (8.4 mol) of 1,4-benzoquinone were obtained. ) And 4.6 g (0.21 mol) of dibutylhydroxytoluene (BHT) were added, and 10.5 L of xylene was added. The mixture was stirred and degassed under reduced pressure, and then the atmosphere in the container was replaced with nitrogen. The mixture was stirred at 130 ° C. for 25 hours.

While heating this mixture to 60 ° C., once with 25 L of 1 mol / L aqueous sodium hydroxide, once with 25 L of 0.5 mol / L aqueous sodium hydroxide, and once with 4.5 L of saturated saline, Washed. After washing, the organic layer in the mixture was concentrated to about 3 L, and 5 L of toluene was added thereto and concentrated. Next, 5 L of toluene is added to this mixture and heated to 60 ° C. to dissolve all solids to form a solution. This solution is purified using Celite (Wako Pure Chemical Industries, Ltd., catalog number: 531-16855) and alumina. did.

The yellow solution obtained by the purification was concentrated and then recrystallized using ethanol and hexane to obtain a target light purple solid in a yield of 459 g and a yield of 82%.

Sublimation purification of 459 g of the obtained pale purple solid was performed by a train sublimation method. Sublimation purification was performed by heating a light purple solid at 205 ° C. under conditions of a pressure of 0.85 Pa and an argon flow rate of 100 mL / min. After purification by sublimation, a target white solid was obtained in a yield of 414 g and a recovery rate of 90%. A synthesis scheme (a-2-2) of Step 2-2 is shown below.

The ¹ H NMR data of the obtained white solid is shown below. ¹ H NMR (CDCl ₃ , 500 MHz): δ = 7.53 (t, J = 7.5 Hz, 2H), 7.66 (d, J = 8.6 Hz, 2H), 7.70 (ddd, J = 7.7, 7, 7, 1.2 Hz, 2H), 7.87 (d, J = 8.6 Hz, 2H), 8.05 (d, J = 8.0 Hz, 2H), 8.71 (s) 1H), 9.22 (d, J = 8.0 Hz, 2H).

Further, the ¹ H NMR chart is shown in FIG. From the measurement results, it was confirmed that the compound obtained in Step 2-2 was the target product shown in Synthesis Scheme (a-2-2), 7H-dibenzo [c, g] carbazole.

Here, purity analysis of the obtained 7H-dibenzo [c, g] carbazole was performed by UPLC. As a result, impurities contained in an area ratio of 0.1% or more as impurities other than 7H-dibenzo [c, g] carbazole were not detected, and the purity was calculated to be 99.9% or more. In the analysis using the mass spectrum, a substance having a mass-to-charge ratio (m / z) = 371 was detected as an impurity as in Step 2-1, but 7H-dibenzo [c, g] carbazole A substance with m / z = 301 which is considered to be an impurity having a structure in which any one hydrogen atom is replaced with chlorine was not detected.

Next, in order to confirm the impurities contained in 7H-dibenzo [c, g] carbazole with high accuracy, measurement was performed using combustion ion chromatography. As a result, the chlorine content in 7H-dibenzo [c, g] carbazole was found to be 1 ppm.

Thus, chlorine-containing impurities contained in 7H-dibenzo [c, g] carbazole were further analyzed by gas chromatography. However, no chlorine-containing impurities were detected. Moreover, it turned out that content of the benzoquinone used as an oxidizing agent in reaction shown to a synthetic scheme (a-2-2) is below a detection minimum.

From the above, it was found that in the synthesis methods of Step 2-1 and Step 2-2, the target product after the reaction hardly contains the oxidizing agent used for the synthesis.

However, in the analysis by the above-mentioned combustion ion chromatography, the content of chlorine contained in 7H-dibenzo [c, g] carbazole due to the difference in the oxidizing agent used in the synthesis reaction (difference in Step 2-1 and Step 2-2). There was a difference in quantity.

From this result, when chlorine is contained in the oxidant, chlorine is added to 7H-dibenzo [c, g] carbazole to generate impurities (hereinafter referred to as chloro adducts), and thus a large amount of chlorine is detected. Can be estimated. The 6,7,8,9-tetrahydro-5H-dibenzo [c, g] carbazole used as a raw material in Step 2-1 and Step 2-2 was synthesized in the same batch in Step 1 above. The purified product was used.

<Step 3-1: Synthesis of cgDBCzPA (1)>
In Step 3-1, cgDBCzPA was synthesized using 7H-dibenzo [c, g] carbazole synthesized in Step 2-1 as a raw material.

In a 50 L reaction vessel, 460 g (1.7 mol) of 7H-dibenzo [c, g] carbazole obtained in Step 2-1 above, 704 g (1.7 mol) of 9- (4-bromophenyl) -10-phenylanthracene were obtained. Then, 486 g (5.1 mol) of sodium tert-butoxide was added, 10.5 L of mesitylene was added, the mixture was stirred while depressurizing and deaerated, and then the atmosphere in the container was replaced with nitrogen.

This mixture was heated to 60 ° C. under a nitrogen stream, and 6.4 g (17 mmol) of allyl palladium (II) chloride dimer and di-tert-butyl (1-methyl-2,2-diphenyl) were added to the degassed mesitylene. A mixture obtained by mixing 24 g (69 mmol) of cyclopropyl) phosphine (cBRIDP (registered trademark)) was added, and the mixture was again deaerated by stirring while reducing the pressure. This mixture was stirred at 155 ° C. for 9 hours under a nitrogen stream.

Next, 10 L of mesitylene and 18 L of water were added and refluxed while stirring. After cooling to 60 ° C., the aqueous layer was separated and removed. Thereafter, the mixture was allowed to cool to room temperature, and the obtained solution was concentrated to about 5 L. The operation of adding 5 L of toluene to this and concentrating it was performed twice. The mixture was refluxed by adding 10 L of toluene, and this solution was treated with Celite (Wako Pure Chemical Industries, Ltd., catalog number: 531-1855), alumina, Florisil (Wako Pure Chemical Industries, Ltd., catalog number: 540-00135). Purified by The filtrate obtained by purification was concentrated and stirred while cooling to about 0 ° C. in an ice bath, and then the solid was separated by suction filtration to obtain the desired pale yellow solid in a yield of 446 g and a yield of 43%.

Sublimation purification of 444 g of the obtained pale yellow solid was performed by a train sublimation method. Sublimation purification was performed by heating a light yellow solid at 355 ° C. under conditions of a pressure of 0.9 Pa and an argon flow rate of 100 mL / min. After the sublimation purification, the target pale yellow solid was obtained in a yield of 332 g with a recovery rate of 75%. A synthesis scheme (a-3) of Step 3-1 is shown below.

The ¹ H NMR data of the obtained pale yellow solid is shown below.

¹ H NMR (CDCl ₃ , 500 MHz): δ = 7.39-7.42 (m, 2H), 7.46-7.50 (m, 2H), 7.53 (d, J = 7.2 Hz, 1H), 7.56-7.60 (m, 12H), 7.96 (d, J = 9.1 Hz, 2H), 8.10 (d, J = 7.4 Hz, 2H), 9.31 ( d, J = 8.0 Hz, 2H).

Further, the ¹ H NMR chart is shown in FIG. From the measurement results, it was confirmed that the compound obtained in Step 3-1 was the target product, cgDBCzPA, shown in Synthesis Scheme (a-3).

<Step 3-2: Synthesis of cgDBCzPA (2)>
In Step 3-2, cgDBCzPA is synthesized using 7H-dibenzo [c, g] carbazole synthesized in Step 2-2 as a raw material.

In a 50 L reaction vessel, 400 g (1.5 mol) of 7H-dibenzo [c, g] carbazole obtained in Step 2-2 above, 9- (4-bromophenyl) -10 in the same lot as in Step 3-1. -612 g (1.5 mol) of phenylanthracene and 431 g (4.5 mol) of sodium tert-butoxide were added, 10 L of mesitylene was added, this mixture was stirred and degassed while reducing the pressure, and then the inside of the container was purged with nitrogen. . The mixture was heated to 60 ° C. under a nitrogen stream, and a mixture of 6.9 g (19 mmol) of allyl palladium (II) chloride dimer and 18 g (52 mmol) of cBRIDP (registered trademark) in degassed mesitylene was added, Again, deaeration was performed by stirring while reducing the pressure, and the inside of the container was purged with nitrogen after deaeration. This mixture was stirred under a nitrogen stream at 135 ° C. for 4 hours and further at 155 ° C. for 3 hours.

Thereafter, 17 L of toluene and 10 L of water were added and refluxed with stirring. After cooling to 75 ° C., the aqueous layer was separated and removed. Thereafter, the mixture was allowed to cool to room temperature, and the obtained solution was concentrated to about 5 L. To this was further added 5 L of toluene and concentrated. To this mixture, 15 L of toluene was added to perform reflux, and this solution was celite (Wako Pure Chemical Industries, Ltd., catalog number: 531-1855), alumina, Florisil (Wako Pure Chemical Industries, Ltd., catalog number: 540-00135). Purified by The filtrate obtained by purification was concentrated and stirred while cooling to about 0 ° C. in an ice bath, and then the solid was separated by suction filtration to obtain the desired pale yellow solid in a yield of 654 g and a yield of 73%.

324 g of the obtained pale yellow solid was purified by sublimation by a train sublimation method. Sublimation purification was performed by heating a light yellow solid at 355 ° C. under conditions of a pressure of 0.9 Pa and an argon flow rate of 100 mL / min. After purification by sublimation, the target pale yellow solid was obtained in a yield of 230 g and a recovery rate of 70%. A synthesis scheme (a-3 ′) of Step 3-2 is shown below.

The ¹ H NMR data of the obtained pale yellow solid is shown below.

¹ H NMR (CDCl ₃ , 500 MHz): δ = 7.39-7.42 (m, 2H), 7.46-7.50 (m, 2H), 7.53 (d, J = 7.2 Hz, 1H), 7.56-7.60 (m, 12H), 7.96 (d, J = 9.1 Hz, 2H), 8.10 (d, J = 6.9 Hz, 2H), 9.31 ( d, J = 8.6 Hz, 2H).

Further, the ¹ H NMR chart is shown in FIG. From the measurement results, it was confirmed that the compound obtained in Step 3-2 was the target product, cgDBCzPA, shown in the synthesis scheme (a-3 ′).

From the above results, among Step 3 (Step 3-1 and Step 3-2), in Step 3-1, the reaction rate is slower than in Step 3-2, and the yield of the synthesized product (cgDBCzPA) is greatly increased. Declined.

In Step 3 (Step 3-1 and Step 3-2), 7H-dibenzo [c, g] carbazole obtained in Step 2 (Step 2-1 and Step 2-2) is used as a raw material. In the case of Step 3-1, which uses 7H-dibenzo [c, g] carbazole synthesized in Step 2-1, as a raw material, there are many chloro adducts in which 7H-dibenzo [c, g] carbazole is an impurity. Therefore, it is considered that the synthesis reaction in Step 3-1 is inhibited.

That is, among Step 3 (Step 3-1 and Step 3-2), the decrease in the reaction rate and the decrease in the yield of the synthesized product (cgDBCzPA) in Step 3-1 are used for the synthesis in Step 3-1. In particular, when synthesizing 7H-dibenzo [c, g] carbazole in Step 2-1, chloranil containing chlorine as an oxidizing agent was used. It is considered that the reaction of Step 3-1 was affected by the chloro adduct produced by the reaction.

The above results shown in this example confirm the effect of the method for synthesizing an organic compound having a condensed carbazole skeleton, which is one embodiment of the present invention, and are used for the synthesis of a compound having a condensed carbazole skeleton as a raw material. It shows that the yield of an organic compound having a condensed carbazole skeleton, which is a synthetic product, is increased by oxidizing using an oxidizing agent not containing chlorine as an agent.

101 First electrode 102 Second electrode 103 EL layer 103a, 103b EL layer 104 Charge generation layer 111, 111a, 111b Hole injection layer 112, 112a, 112b Hole transport layer 113, 113a, 113b Light emitting layer 114, 114a , 114b Electron transport layers 115, 115a, 115b Electron injection layers 200R, 200G, 200B Optical distance 201 First substrate 202 Transistor (FET)
203R, 203G, 203B, 203W Light emitting element 204 EL layer 205 Second substrate 206R, 206G, 206B Color filter 206R ′, 206G ′, 206B ′ Color filter 207 First electrode 208 Second electrode 209 Black layer (black matrix )
210R, 210G Conductive layer 301 First substrate 302 Pixel portion 303 Drive circuit portion (source line drive circuit)
304a, 304b Drive circuit section (gate line drive circuit)
305 Sealing material 306 Second substrate 307 Route wiring 308 FPC
309 FET
310 FET
311 FET
312 FET
313 First electrode 314 Insulator 315 EL layer 316 Second electrode 317 Light emitting element 318 Space 900 Substrate 901 First electrode 902 EL layer 903 Second electrode 911 Hole injection layer 912 Hole transport layer 913 Light emitting layer 914 Electron transport layer 915 Electron injection layer 4000 Lighting device 4001 Substrate 4002 Light emitting element 4003 Substrate 4004 First electrode 4005 EL layer 4006 Second electrode 4007 Electrode 4008 Electrode 4009 Auxiliary wiring 4010 Insulating layer 4011 Sealing substrate 4012 Sealing material 4013 Desiccant 4015 Diffuser 4200 Lighting device 4201 Substrate 4202 Light emitting element 4204 First electrode 4205 EL layer 4206 Second electrode 4207 Electrode 4208 Electrode 4209 Auxiliary wiring 4210 Insulating layer 4211 Sealing substrate 4212 Sealing material 4213 Barrier film 4214 Flat Chemical film 4215 Diffusion plate 5101 Light 5102 Wheel 5103 Door 5104 Display unit 5105 Handle 5106 Shift lever 5107 Seat seat 5108 Inner rear view mirror 7000 Case 7001 Display unit 7002 Second display unit 7003 Speaker 7004 LED lamp 7005 Operation key 7006 Connection terminal 7007 Sensor 7008 Microphone 7009 Switch 7010 Infrared port 7011 Recording medium reading unit 7012 Support unit 7013 Earphone 7014 Antenna 7015 Shutter button 7016 Image receiving unit 7018 Stand 7020 Camera 7021 External connection unit 7022 and 7023 Operation button 7024 Connection terminal 7025 Band,
7026 Clasp 7027 Icon 7028 Other Time Icon 9310 Portable Information Terminal 9311 Display Unit 9312 Display Area 9313 Hinge 9315 Case

Claims (4)

  A method for synthesizing an organic compound having a condensed carbazole skeleton, comprising coupling a compound having a condensed carbazole skeleton having a chlorine content of 10 ppm or less and a halogenated aryl compound or a halogenated heteroaryl compound. In claim 1,
The method for synthesizing an organic compound having a condensed carbazole skeleton, wherein the compound having the condensed carbazole skeleton has a chlorine content of 5 ppm or less. A condensed carbazole skeleton characterized by coupling a compound having a chlorine content of 10 ppm or less and having a condensed carbazole skeleton represented by the general formula (G0) with a halogenated aryl compound or a halogenated heteroaryl compound A method for synthesizing an organic compound having

(In the formula, at least one of positions a to c or g to i has a condensed structure with a substituted or unsubstituted benzene ring. In addition, R ^{1 to 8} each independently represent hydrogen or carbon number. A 1 to 6 alkyl group or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, and n and m each represents an integer of 1 to 4)   An organic compound having a condensed carbazole skeleton, characterized by coupling a compound having a condensed carbazole skeleton obtained by a synthesis method using an oxidizing agent containing no chlorine and a halogenated aryl compound or a halogenated heteroaryl compound. Compound synthesis method.