TWI795042B - Boron-containing compound, light-emitting material and light-emitting element using the same - Google Patents

Abstract

The present invention provides a formula (I) (wherein, R ¹ , R ² , R ³ , R ⁴ , R ⁵ and R ⁶ are substituted or unsubstituted alkyl groups, and m is independently any of 0-4. An integer, n is independently any integer from 0 to 3, Y is NR ⁷ , O or S, Z is NR ⁸ , O or S, R ⁷ and R ⁸ are independently a hydrogen atom, substituted or unsubstituted A substituted alkyl group or a substituted or unsubstituted aryl group, when ^R7 is a substituted or unsubstituted aryl group, the aryl group can be linked to the A1 ring to form a condensed ring, and ^R8 is substituted or an unsubstituted aryl group, the aryl group can be linked with the A2 ring to form a condensed ring), etc.

Description

Boron-containing compound, light-emitting material and light-emitting element using the same

The invention relates to a boron-containing compound, a light-emitting material and a light-emitting element using the same. More specifically, the present invention relates to a boron-containing compound with excellent luminescent properties, a luminescent material and a luminescent device using the same.

As a light-emitting material, for example, Patent Document 1 proposes the following boron-containing compounds.

[先前技術文獻] [專利文獻]

[Prior Art Document] [Patent Document]

[Patent Document 1] US2020/0270278A1

[Problem to be Solved by the Invention]

The object of the present invention is to provide a novel boron-containing compound excellent in light-emitting properties, a light-emitting material, and a light-emitting device using the same. [Technical means to solve the problem]

As a result of earnest research to solve the above-mentioned problems, the present invention including the following aspects has been completed.

That is, the present invention is [1] A compound represented by formula (I).

In formula (I), R ¹ , R ² , R ³ , R ⁴ , R ⁵ and R ⁶ are independently substituted or unsubstituted alkyl groups, and m is independently any integer from 0 to 4, n are independently any integer from 0 to 3, Y is NR ⁷ , O or S, Z is NR ⁸ , O or S, R ⁷ and R ⁸ are independently a hydrogen atom, substituted or unsubstituted Alkyl or substituted or unsubstituted aryl, when R ⁷ is substituted or unsubstituted aryl, the aryl can be linked with A1 ring to form a condensed ring, and R ⁸ is substituted or unsubstituted In the case of a substituted aryl group, the aryl group may link with the A2 ring to form a condensed ring.

[2] The compound as described in [1], which is represented by the formula (II).

In formula (II), R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁹ and R ¹⁰ are independently substituted or unsubstituted alkyl groups, and m are independently 0 to any integer of 4, and n are each independently any integer of 0-3.

[3] A light-emitting material comprising the compound described in [1] or [2].

[4] A light-emitting device comprising the light-emitting material described in [3]. [Effect of Invention]

The boron-containing compound of the present invention is useful as a light-emitting material. Among the luminescent materials of the present invention are those that emit delayed fluorescence. A light-emitting element containing the light-emitting material of the present invention can achieve excellent luminous efficiency.

The boron-containing compound of the present invention is a compound represented by formula (I), preferably a compound represented by formula (II).

In formula (I), R ¹ , R ² , R ³ , R ⁴ , R ⁵ and R ⁶ are independently substituted or unsubstituted alkyl groups, and m is independently any integer from 0 to 4, n are independently any integer from 0 to 3, Y is NR ⁷ , O or S, Z is NR ⁸ , O or S, R ⁷ and R ⁸ are independently a hydrogen atom, substituted or unsubstituted Alkyl or substituted or unsubstituted aryl, when R ⁷ is substituted or unsubstituted aryl, the aryl can be linked with A1 ring to form a condensed ring, and R ⁸ is substituted or unsubstituted In the case of a substituted aryl group, the aryl group may link with the A2 ring to form a condensed ring.

In formula (II), R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁹ and R ¹⁰ are independently substituted or unsubstituted alkyl groups, and m are independently 0 to any integer of 4, and n are each independently any integer of 0-3.

In the present invention, the term "unsubstituted" means only a base that becomes the core. When there is no description of "substituted" but only the name of the base that becomes the mother nucleus, unless otherwise specified, it means "unsubstituted". On the other hand, the term "substituted" means that any hydrogen atom that becomes the base of the parent nucleus is replaced by a group (substituent) of the same or different structure as the parent nucleus. Therefore, a "substituent" is another group bonded to the group that becomes the parent nucleus. One or more substituents may be used. Two or more substituents may be the same or different. Terms such as "C1-6" indicate that the number of carbon atoms serving as the base of the mother nucleus is 1-6. The number of carbon atoms present in the substituent is not included in the number of carbon atoms. For example, a butyl group having an ethoxy group as a substituent is classified as a C2 alkoxy C4 alkyl group.

The "substituent" is not particularly limited as long as it is chemically acceptable and has the effect of the present invention. Groups which may be used as "substituents" are exemplified below. Methyl, ethyl, n-propyl, isopropyl, n-butyl, second butyl, isobutyl, third butyl, n-pentyl, n-hexyl and other C1-6 alkyl groups; Vinyl, 1-propenyl, 2-propenyl (allyl), 1-butenyl, 2-butenyl, 3-butenyl, 1-methyl-2-propenyl, 2-methyl C2-6 alkenyl such as -2-propenyl; Ethynyl, 1-propynyl, 2-propynyl, 1-butynyl, 2-butynyl, 3-butynyl, 1-methyl-2-propynyl and other C2-6 alkynyl groups;

Cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl and other C3-6 cycloalkyl groups; Phenyl, naphthyl; 3-6 membered heterocyclic group;

Methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, second butoxy, isobutoxy, third butoxy and other C1-6 alkoxy groups; C6-10 aryloxy groups such as phenoxy and naphthyloxy; Heteroaryloxy with 5-6 members such as thiazolyloxy, pyridyloxy, etc.;

C1-6 alkoxycarbonyl such as methoxycarbonyl, ethoxycarbonyl, n-propoxycarbonyl, isopropoxycarbonyl, n-butoxycarbonyl, tertiary butoxycarbonyl, etc.;

Fluorine, chlorine, bromine, iodine and other halogen groups; Chloromethyl, chloroethyl, trifluoromethyl, 1,2-dichloro-n-propyl, 1-fluoro-n-butyl, perfluoro-n-pentyl and other C1-6 haloalkyl groups; C1-6 haloalkoxy such as trifluoromethoxy, 2-chloro-n-propoxy, 2,3-dichlorobutoxy;

Formamide group; C1-6 alkylcarbonylamine groups such as acetamide group, propionylamino group, butyramide group, isopropylcarbonylamino group, etc.; Methoxycarbonylamine, ethoxycarbonylamine, n-propoxycarbonylamine, isopropoxycarbonylamine and other C1-6 alkoxycarbonylamine groups; Aminocarbonyl, dimethylaminocarbonyl, phenylaminocarbonyl, N-phenyl-N-methylaminocarbonyl and other unsubstituted or substituted aminocarbonyl groups;

Methylthio, ethylthio, n-propylthio, isopropylthio, n-butylthio, isobutylthio, second butylthio, third butylthio and other C1-6 alkylthio groups; Trifluoromethylthio, 2,2,2-trifluoroethylthio and other C1-6 haloalkylthio groups; Methylsulfonyl, ethylsulfonyl, tertiary butylsulfonyl and other C1-6 alkylsulfonyl groups; C1-6 haloalkylsulfonyl groups such as trifluoromethylsulfonyl, 2,2,2-trifluoroethylsulfonyl;

cyano; nitro;

Also, regarding these "substituents", any hydrogen atom in the substituent may be substituted by a group of a different structure. Examples of the substituent in this case include a C1-6 alkyl group, a C1-6 haloalkyl group, a C1-6 alkoxy group, a C1-6 haloalkoxy group, a halo group, a cyano group, and a nitro group.

基、

啉基、二氧雜環戊基（dioxolanyl）、二氧雜環己基（dioxanyl）等。 作為5員之雜芳基，可列舉：吡咯基、呋喃基、噻吩基、咪唑基、吡唑基、

唑基、異

唑基、噻唑基、異噻唑基、三唑基、

二唑基（oxadiazolyl）、噻二唑基（thiadiazolyl）、四唑基等。 作為6員之雜芳基，可列舉：吡啶基、吡

基、嘧啶基、嗒

基、三

基等。 Also, the aforementioned "3- to 6-membered heterocyclic group" refers to one containing 1 to 4 heteroatoms selected from the group consisting of nitrogen atoms, oxygen atoms and sulfur atoms as constituent atoms of the ring. The heterocyclic group may be either monocyclic or polycyclic. In the polycyclic heterocyclic group, if at least one ring is a heterocyclic ring, the remaining rings may be any of saturated alicyclic rings, unsaturated alicyclic rings or aromatic rings. Examples of the "3- to 6-membered heterocyclic group" include 3-6-membered saturated heterocyclic group, 5-6-membered heteroaryl group, 5-6-membered partially unsaturated heterocyclic group, and the like. Examples of saturated heterocyclic groups with 3 to 6 members include: aziridinyl, epoxy, pyrrolidinyl, tetrahydrofuranyl, thiazolidinyl, piperidinyl, piperidine

base,

Linyl, dioxolanyl (dioxolanyl), dioxanyl (dioxanyl), etc. Examples of the 5-membered heteroaryl group include pyrrolyl, furyl, thienyl, imidazolyl, pyrazolyl,

Azolyl, iso

Azolyl, thiazolyl, isothiazolyl, triazolyl,

Oxadiazolyl, thiadiazolyl, tetrazolyl, etc. Examples of the 6-membered heteroaryl include: pyridyl, pyridyl

base, pyrimidinyl, pyridyl

base, three

Base etc.

The alkyl groups in R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ and R ¹⁰ in formula (I) or (II) can be straight chain or for the branch chain. The number of constituent carbon atoms is preferably from 1 to 6. Examples of the alkyl group include methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, isopropyl, isobutyl, second-butyl, third-butyl, isopentyl, Neopentyl, 2-methylbutyl, 2,2-dimethylpropyl, isohexyl, etc.

Examples of substituents on the "alkyl group" include halogen groups such as fluorine, chlorine, bromine, and iodine; hydroxyl; methoxy, ethoxy, n-propoxy, isopropoxy, and n-butyl. Oxygen, second butoxy, isobutoxy, third butoxy and other C1-6 alkoxy groups; 2-chloro-n-propoxy, 2,3-dichlorobutoxy, trifluoromethoxy Etc. C1～6 haloalkoxy; phenyl; 4-chlorophenyl, 4-trifluoromethylphenyl, 4-trifluoromethoxyphenyl, etc. through halogen group, C1～6 haloalkyl or C1～ 6 phenyl substituted with haloalkoxy; or cyano.

Examples of the aryl group in R ⁷ and R ⁸ in formula (I) include phenyl and naphthyl. Examples of substituents on "phenyl" or "naphthyl" include halogen groups such as fluoro, chloro, bromo, and iodo; methyl, ethyl, n-propyl, isopropyl, and n-butyl , second butyl, isobutyl, third butyl, n-pentyl, n-hexyl and other C1-6 alkyl groups; chloromethyl, chloroethyl, trifluoromethyl, 1,2-dichloro-n-propyl , 1-fluoro-n-butyl and other C1-6 haloalkyl groups; hydroxyl; methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, second butoxy, isobutoxy , tertiary butoxy and other C1-6 alkoxy groups; 2-chloro-n-propoxy, 2,3-dichlorobutoxy, trifluoromethoxy and other C1-6 haloalkoxy groups; or cyano.

When R ⁷ is a substituted or unsubstituted aryl group, the aryl group can be linked with the A1 ring to form a condensed ring. When R ⁸ is a substituted or unsubstituted aryl group, the aryl group can be linked with the A2 ring to form a condensed ring.

Specific examples of the boron-containing compound of the present invention include the following. However, these are merely examples, and the present invention is not limited to the examples.

The boron-containing compound of the present invention can be obtained by combining known synthesis reactions (such as coupling reactions, substitution reactions, etc.).

For example, BBCz-R, which is one of the compounds represented by formula (I), can be obtained as follows, for example.

(example 1)

Add t-BuOK (2.24 g, 20.0 mmol), dehydrated DMF (180 mL) and 3,6-di-tert-butyl-carbazole (5.58 g, 20.0 mmol) to a 300 mL Schlenk flask (Schlenk flask) ), and stirred at room temperature for 30 minutes. 2-Bromo-1,3-difluorobenzene (5.78 g, 30.0 mmol) was added thereto, and reflux was performed for 24 hours. The obtained liquid was poured into water, followed by adding dichloromethane for extraction. Magnesium sulfate was added to the obtained organic layer, it was dried, filtered, and it concentrated with the rotary evaporator. The concentrate was separated and purified by silica gel column chromatography (n-hexane/chloroform=4/1) to obtain 4.51 g of BCz-Br as a white solid (50% yield). ¹ H-NMR (400 MHz, CDCl ₃ , δ): 8.13 (d, J = 1.4 Hz, 2H), 7.48-7.45 (m, 1H), 7.43 (dd, J = 8.8, 2.0 Hz, 2H), 7.31 -7.26 (m, 2H), 6.99-6.94 (m, 2H), 1.45 (s, 18H)

Add t-BuOK (2.81 g, 25.0 mmol), dehydrated DMF (180 mL) and 2,8-di-tert-butyl-5,11-dihydroindolo[3, 2-b] carbazole (3.69 g, 10.0 mmol), and stirred at room temperature for 30 minutes. BCz-Br (11.30 g, 25.0 mmol) was added thereto, and reflux was performed for 24 hours. The obtained liquid was poured into water, followed by adding dichloromethane for extraction. Magnesium sulfate was added to the obtained organic layer, and it dried, and it filtered and concentrated with the rotary evaporator. The concentrate was separated and purified by silica gel column chromatography (n-hexane/chloroform=3/1) to obtain 4.82 g of 2BCz-INCz-Br as a white solid (yield 39%). ¹ H-NMR (400 MHz, CDCl ₃ , δ): 8.21-8.18 (m, 6H), 7.85 (s, 2H), 7.78-7.70 (m, 6H), 7.59-7.53 (m, 6H), 7.32 ( d, J = 8.8 Hz, 2H), 7.20 (dd, J = 8.5, 6.0 Hz, 4H), 1.52 (s, 19H), 1.49 (d, J = 2.0 Hz, 36H).

2BCz-INCz-Br (1.11 g, 0.90 mmol) and dehydrated tert-butylbenzene (120 mL) were added to a 300 mL Schlenk flask. Next, nitrogen substitution was performed. Thereto was added n-butyllithium (1.7 mL, 1.6 M, 2.70 mmol) in small portions at 0° C., and stirred at room temperature for 4 hours. To this was added boron tribromide (0.30 mL, 2.70 mol) in small amounts at 0°C, and stirred overnight at room temperature. Next, N,N-diisopropylethylamine (0.70 mL, 4.05 mmol) was added at 0°C, followed by stirring at 170°C for 24 hours. The obtained liquid was brought to room temperature and poured into water. Thereafter, chloroform was added for extraction. The obtained organic layer was filtered. The filtrate was washed with water. Then, magnesium sulfate was added, it dried, and it concentrated with the rotary evaporator. The concentrate was separated and purified by silica gel column chromatography (n-hexane/chloroform=9/1) to obtain 0.054 g of black crystals of BBCz-R (5% yield). ¹ H-NMR (400 MHz, CDCl ₃ , δ): 8.67 (d, J = 1.8 Hz, 2H), 8.46 (d, J = 8.8 Hz, 2H), 8.43-8.31 (m, 12H), 8.10 (t , J = 8.2 Hz, 2H), 7.74 (dd, J = 8.5, 2.0 Hz, 2H), 7.51 (dd, J = 8.5, 1.8 Hz, 2H), 1.58 (s, 18H), 1.32 (s, 18H) , 1.09 (s, 18H)

Purification of the synthesized compound can be carried out by purification using column chromatography, adsorption purification using silica gel, activated carbon, activated clay, etc., recrystallization or crystallization using a solvent, and the like. Identification of the compound can be performed by NMR analysis or the like.

The boron-containing compound of the present invention can be used as a luminescent material. The light-emitting material of the present invention can provide light-emitting elements such as organic photoluminescent elements and organic electroluminescent elements. The boron-containing compound of the present invention has the function of assisting the light emission of other luminescent materials (host materials), so it can be doped into other luminescent materials for use.

The organic photoluminescent device of the present invention is formed by disposing a light-emitting layer containing the light-emitting material of the present invention on a substrate. The light-emitting layer can be obtained by a coating method such as spin coating, a printing method such as inkjet printing, a vapor deposition method, and the like.

The organic electroluminescent device of the present invention is formed by providing an organic layer between the anode and the cathode. The "organic layer" in the present invention means a layer substantially composed of organic substances located between the anode and the cathode, and these layers may contain inorganic substances within the range that does not impair the performance of the light-emitting device of the present invention.

As the structure in one embodiment of the organic electroluminescent element of the present invention, it can be listed: on the substrate, an anode, a hole injection layer, a hole transport layer, an electron blocking layer, a light emitting layer, a hole blocking layer, The electron transport layer and the cathode constitute; and the electron injection layer is further provided between the electron transport layer and the cathode. In these multilayer structures, several layers of organic layers can be omitted, for example, an anode, a hole transport layer, a light-emitting layer, an electron transport layer, an electron injection layer, and a cathode can be sequentially arranged on the substrate, and an anode, a hole transport layer, and a cathode can also be arranged. layer, light emitting layer, electron transport layer, cathode. The light-emitting material of the present invention can be doped not only in the light-emitting layer, but also in the hole injection layer, hole transport layer, electron blocking layer, hole blocking layer, electron transport layer or electron injection layer.

The substrate serves as a support for the light-emitting device, and silicon plates, quartz plates, glass plates, metal plates, metal foils, resin films, resin sheets, and the like can be used. In particular, a glass plate or a plate of transparent synthetic resin such as polyester, polymethacrylate, polycarbonate, and polyester is preferable. When using a synthetic resin substrate, attention must be paid to gas barrier properties. If the gas barrier property of the substrate is too low, the light-emitting element may be degraded by the outside air passing through the substrate. Therefore, it is preferable to provide a dense silicon oxide film or the like on either one side or both sides of the synthetic resin substrate to ensure gas barrier properties.

An anode is set on the substrate. The anode generally uses a material with a large work function. Examples of materials for the anode include metals such as aluminum, gold, silver, nickel, palladium, and platinum; metal oxides such as indium oxide, tin oxide, ITO, zinc oxide, In ₂ O ₃ -ZnO, and IGZO; iodine Metal halides such as copper chloride, conductive polymers such as carbon black or poly(3-methylthiophene), polypyrrole, and polyaniline, etc. The formation of the anode is generally performed by a sputtering method, a vacuum evaporation method, or the like in many cases. Also, in the case of metal fine particles such as silver, fine particles such as copper iodide, carbon black, conductive metal oxide fine particles, conductive polymer fine powder, etc., it can also be dispersed in an appropriate binder resin solution, and Coated on the substrate to form the anode. Furthermore, in the case of a conductive polymer, it is also possible to form a thin film directly on the substrate by electrolytic polymerization or to coat the conductive polymer on the substrate to form an anode.

The anode can also be formed by laminating two or more different substances. The thickness of the anode varies according to the desired transparency. When transparency is required, it is desirable to set the transmittance of visible light to 60% or more, preferably 80% or more. In this case, the thickness is usually 10-1000 nm, preferably 10-200 nm . When it may be opaque, the anode may have the same thickness as the substrate. The sheet resistance of the anode is preferably several hundred Ω/□ or more.

As an optional hole injection layer, in addition to porphyrin compounds represented by copper phthalocyanine, naphthalene diamine derivatives, starburst triphenylamine derivatives, and three or more triphenylamine structures in the molecule can also be used. Triphenylamine trimers and tetramers such as arylamine compounds with structures linked by single bonds or divalent groups without heteroatoms, acceptor heterocyclic compounds such as hexacyanoazatriphenylene, or Coating type polymer material. These materials can also be formed into a thin film by a known method such as a spin coating method or an inkjet method in addition to the vapor deposition method.

As the hole transport material used for the optional hole transport layer, it is preferable that the hole injection efficiency from the anode is high, and the injected holes can be transported efficiently. Therefore, it is preferable that the ionization potential is small, the transparency to visible light is high, the hole mobility is large, and the stability is excellent, and impurities that become traps are less likely to be generated during manufacture or use. In addition to the above general requirements, when considering the application of vehicle display applications, it is better to have higher heat resistance for components. Therefore, it is desirable as a material having a Tg value of 70° C. or higher.

二唑衍生物、咪唑衍生物、咔唑衍生物、吲哚并咔唑衍生物、多芳基烷烴衍生物、吡唑啉衍生物、吡唑哢衍生物、苯二胺衍生物、芳基胺衍生物、胺基取代查耳酮衍生物、

唑衍生物、苯乙烯基蒽衍生物、茀酮衍生物、腙衍生物、茋衍生物、矽氮烷衍生物、苯胺系共聚物、導電性高分子低聚物等。更具體而言，可列舉：含有間咔唑基苯基之化合物、N,N'-二苯基-N,N'-二(間甲苯基)-聯苯胺（以下簡稱為TPD）、N,N'-二苯基-N,N'-二(α-萘基)-聯苯胺（以下簡稱為NPD）、N,N,N',N'-四聯苯基聯苯胺等聯苯胺衍生物、1,1-雙[(二-4-甲苯基胺基)苯基]環己烷（以下簡稱為TAPC）、各種三苯胺三聚物及四聚物或咔唑衍生物等。該等可單獨使用1種或將2種以上加以組合而使用。電洞傳輸層可為單層構造之膜，亦可為積層構造之膜。又，作為電洞之注入/傳輸層，可使用聚(3,4-伸乙二氧基噻吩)（以下簡稱為PEDOT）/聚(苯乙烯磺酸鹽)（以下簡稱為PSS）等塗佈型之高分子材料。該等材料除蒸鍍法以外，亦可藉由旋轉塗佈法或噴墨法等公知之方法而進行薄膜形成。Examples of the optional hole transport layer include triazole derivatives,

Oxadiazole derivatives, imidazole derivatives, carbazole derivatives, indolocarbazole derivatives, polyaryl alkane derivatives, pyrazoline derivatives, pyrazolium derivatives, phenylenediamine derivatives, arylamines derivatives, amino-substituted chalcone derivatives,

Azole derivatives, styryl anthracene derivatives, stilone derivatives, hydrazone derivatives, stilbene derivatives, silazane derivatives, aniline copolymers, conductive polymer oligomers, etc. More specifically, compounds containing m-carbazolylphenyl, N,N'-diphenyl-N,N'-bis(m-tolyl)-benzidine (hereinafter abbreviated as TPD), N, N'-diphenyl-N,N'-bis(α-naphthyl)-benzidine (hereinafter referred to as NPD), N,N,N',N'-quaterphenylbenzidine and other benzidine derivatives , 1,1-bis[(di-4-tolylamino)phenyl]cyclohexane (hereinafter referred to as TAPC), various triphenylamine trimers and tetramers or carbazole derivatives, etc. These can be used individually by 1 type or in combination of 2 or more types. The hole transport layer may be a film with a single-layer structure or a film with a laminated structure. In addition, as the hole injection/transport layer, poly(3,4-ethylenedioxythiophene) (hereinafter referred to as PEDOT)/poly(styrene sulfonate) (hereinafter referred to as PSS) and other coatings can be used. type of polymer material. These materials can also be formed into a thin film by a known method such as a spin coating method or an inkjet method in addition to the vapor deposition method.

In addition, in the hole injection layer or the hole transport layer, it can be used in the material commonly used in this layer and then P-doped with tribromophenylamine hexachloroantimony, or its partial structure has a high PD structure. molecular compounds, etc. As a host material for hole injection/transport properties, carbazole derivatives such as CBP, TCTA, and mCP can be used.

Preferred compounds (hi1) to (hi7) that can be used as hole injection materials are listed below.

Preferred compounds (ht1) to (ht38) that can be used as hole transport materials are listed below.

As an optional electron blocking layer, 4,4',4''-tris(N-carbazolyl)triphenylamine (hereinafter referred to as TCTA), 9,9-bis[4-(carbazole-9 -yl)phenyl] fennel, 1,3-bis(carbazol-9-yl)benzene (hereinafter referred to as mCP), 2,2-bis(4-carbazol-9-ylphenyl)adamantane (hereinafter Abbreviated as Ad-Cz), carbazole derivatives such as 9-[4-(carbazol-9-yl)phenyl]-9-[4-(triphenylsilyl)phenyl]-9H- Representative compounds with triphenylsilyl and triarylamine structures and other compounds with electron blocking effect. These can be used individually by 1 type or in combination of 2 or more types. The electron blocking layer may be a film with a single-layer structure or a film with a laminated structure. These materials can also be formed into a thin film by a known method such as a spin coating method or an inkjet method in addition to the vapor deposition method.

Preferred compounds (es1) to (es5) that can be used as electron blocking materials are listed below.

唑衍生物、聚對伸苯乙烯（polyparaphenylene vinylene）衍生物、具有聯吡啶基及鄰聯三苯基結構之化合物、mCP、噻唑衍生物、苯并咪唑衍生物、聚二烷基茀衍生物等。發光層中亦可包含公知之摻雜劑。作為摻雜劑，可列舉：喹吖酮、香豆素、紅螢烯、蒽、苝及該等之衍生物、苯并哌喃衍生物、玫瑰紅衍生物、胺基苯乙烯基衍生物等。又，亦可使用Ir(ppy)3等綠色之磷光發光體、FIrpic、FIr6等藍色之磷光發光體、Btp2Ir(acac)等紅色之磷光發光體等磷光性之發光體。該等可單獨使用1種或將2種以上加以組合而使用。發光層可為單層構造之膜，亦可為積層構造之膜。該等材料除蒸鍍法以外，亦可藉由旋轉塗佈法或噴墨法等公知之方法而進行薄膜形成。 於使用主體材料之情形時，發光層中可含有之本發明之發光材料之量之下限較佳為0.1質量%，更佳為1質量%，上限較佳為50質量%，更佳為20質量%，進而較佳為10質量%。 The light-emitting layer is a layer having a function of generating excitons by recombination of holes and electrons injected from each of the anode and the cathode to emit light. The light-emitting layer can be formed solely from the light-emitting material of the present invention, or can be formed by doping the light-emitting material of the present invention into the host material. Examples of host materials include: metal complexes of oxyquinoline derivatives such as tris(8-quinolinolato)aluminum (hereinafter referred to as Alq3), anthracene derivatives, bistyrylbenzene derivatives, pyrene derivatives, etc. things,

Azole derivatives, polyparaphenylene vinylene derivatives, compounds with bipyridyl and ortho-terphenyl structures, mCP, thiazole derivatives, benzimidazole derivatives, polydialkylfenene derivatives, etc. . Known dopants may also be included in the light emitting layer. Examples of dopants include quinacridone, coumarin, rubrene, anthracene, perylene and their derivatives, benzopyran derivatives, rose bengal derivatives, aminostyryl derivatives, etc. . In addition, phosphorescent emitters such as green phosphorescent emitters such as Ir(ppy)3, blue phosphorescent emitters such as FIrpic and FIr6, and red phosphorescent emitters such as Btp2Ir(acac) can also be used. These can be used individually by 1 type or in combination of 2 or more types. The light-emitting layer may be a single-layer film or a laminated film. These materials can also be formed into a thin film by a known method such as a spin coating method or an inkjet method in addition to the vapor deposition method. When a host material is used, the lower limit of the amount of the light-emitting material of the present invention that can be contained in the light-emitting layer is preferably 0.1% by mass, more preferably 1% by mass, and the upper limit is preferably 50% by mass, more preferably 20% by mass %, and more preferably 10% by mass.

The preferred compounds (el1) to (el40) that can be used as the host material of the light-emitting layer are listed below.

唑衍生物、三唑衍生物、三

衍生物等具有電洞阻擋作用之化合物。該等材料亦可兼作電子傳輸層之材料。該等可單獨使用1種或將2種以上加以組合而使用。電洞阻擋層可為單層構造之膜，亦可為積層構造之膜。該等材料除蒸鍍法以外，亦可藉由旋轉塗佈法或噴墨法等公知之方法而進行薄膜形成。As an optional hole blocking layer, there are compounds with bipyridyl and o-terphenyl structures, phenanthroline derivatives such as bathocuproine (hereinafter referred to as BCP), or bis(2-methanol) Metal complexes of oxyquinoline derivatives such as -8-quinoline)-4-phenylphenol aluminum (III) (hereinafter referred to as BAlq), various rare earth complexes,

Azole derivatives, triazole derivatives, three

Derivatives and other compounds with hole blocking effect. These materials can also serve as materials for the electron transport layer. These can be used individually by 1 type or in combination of 2 or more types. The hole blocking layer may be a single-layer film or a laminated film. These materials can also be formed into a thin film by a known method such as a spin coating method or an inkjet method in addition to the vapor deposition method.

The preferred compounds (hs1) to (hs11) that can be used as hole blocking materials are listed below.

衍生物、

二唑衍生物、噻二唑衍生物、碳二醯亞胺衍生物、喹

啉衍生物、啡啉衍生物、噻咯衍生物（silole derivative）等。該等可單獨使用1種或將2種以上加以組合而使用。電子傳輸層可為單層構造之膜，亦可為積層構造之膜。該等材料除蒸鍍法以外，亦可藉由旋轉塗佈法或噴墨法等公知之方法而進行薄膜形成。As an optional electron transport layer, in addition to metal complexes of oxyquinoline derivatives represented by Alq3 and BAlq, various metal complexes, triazole derivatives, triazole

derivative,

Oxadiazole derivatives, thiadiazole derivatives, carbodiimide derivatives, quinone

phenanthroline derivatives, phenanthroline derivatives, silole derivatives, etc. These can be used individually by 1 type or in combination of 2 or more types. The electron transport layer may be a film with a single-layer structure or a film with a laminated structure. These materials can also be formed into a thin film by a known method such as a spin coating method or an inkjet method in addition to the vapor deposition method.

As the optional electron injection layer, alkali metal salts such as lithium fluoride and cesium fluoride, alkaline earth metal salts such as magnesium fluoride, metal oxides such as aluminum oxide, etc. can be used. selected, it can be omitted.

In the electron injection layer or the electron transport layer, those obtained by N-doping metals such as cesium can be used in materials generally used in the layer.

Preferred compounds (et1) to (et30) that can be used as electron transport materials are listed below.

Preferred compounds (ei1) to (ei4) that can be used as electron injection materials are listed below.

Preferred compounds (st1) to (st5) that can be used as stabilizing materials are listed below.

The cathode generally uses a material with a smaller work function. As materials for the cathode, for example, sodium, sodium-potassium alloy, lithium, tin, magnesium, magnesium/copper mixture, magnesium/aluminum mixture, magnesium/indium mixture, aluminum/alumina mixture, indium, calcium, aluminum, silver, Lithium/aluminum mixture, magnesium-silver alloy, magnesium-indium alloy, aluminum-magnesium alloy, etc. By using transparent conductive materials, transparent or translucent cathodes can be obtained. The thickness of the cathode is usually 10-5000 nm, preferably 50-200 nm. The sheet resistance of the cathode is preferably several hundred Ω/□ or more.

Furthermore, in order to protect the cathode composed of metals with low work function, if aluminum, silver, nickel, chromium, gold, platinum and other metal layers with high work function and stable to the atmosphere are further laminated on it, the stability of the device will be enhanced. , so it is better. In addition, in order to improve the contact between the cathode and the adjacent organic layer (such as the electron transport layer or electron injection layer), a cathode interface layer can also be provided between the two. Examples of materials used in the cathode interface layer include aromatic diamine compounds, quinacridone compounds, condensed tetraphenyl derivatives, organosilicon compounds, organophosphorus compounds, compounds with N-phenylcarbazole skeletons, N- Vinyl carbazole polymers, etc.

The light-emitting device of the present invention can be applied to any of a single device, a device having a structure arranged in an array, and a structure in which anodes and cathodes are arranged in an X-Y matrix.

Regarding the embodiments of the present invention, the effects thereof will be shown below.

The evaluation of luminescence characteristics used SourceMeter (manufactured by Keithley: 2400 series), spectroradiometer (manufactured by Konica Minolta: CS-2000), spectrofluorophotometer (manufactured by JASCO Corporation: FP-8600) ) and 100 mmΦ integrating sphere (manufactured by JASCO Corporation: ILF-835).

(Example 2) Prepare a toluene solution of BBCz-R in a nitrogen atmosphere glove box. The solution was subjected to PL spectrometry. The results are shown in Fig. 1 .

BBCz-R:

( ^Example 3) 10 nm thick 2,3, 6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazabiterylene (HAT-CN) film, 1,1-bis[4- [N,N-di(p-tolyl)amino]phenyl]cyclohexane (TAPC) film, 10 nm thick mCBP film, 20 nm thick 2 wt% BBCz-R:mCBP film, 10 nm thick 2,8-bis(diphenylphosphoryl)dibenzo[b,d]furan (PPF) film, 40 nm thick 1,3-bis[3,5-bis(pyridin-3-yl)benzene base] benzene (B3PyPB) film.

Then, a cathode was formed by sequentially laminating a 1 nm thick 8-hydroxyquinolinato lithium film and a 100 nm thick aluminum film by vacuum evaporation, thereby obtaining an organic electroluminescence device. The characteristics of the organic electroluminescent device are measured. The emission characteristics are shown in Table 1. FIG. 2 shows current density-external quantum efficiency characteristics. The voltage-current density characteristic is shown in FIG. 3 .

[Table 1] Table 1 _λEL [nm] λ _FWHM [nm] E _FWHM [eV] V _on [V] L _max [cdm ^-2 ] EQE _Max [%] EQE @100 cdm ^-2 [%] EQE @1000 cdm ^-2 [%] CE _max [cdA ^-1 ] PE _max [1 mW ^-1 ] CIE (x, y) 615 26 0.09 4.6 500 22.0 6.0 - 35.7 24.3 (0.67, 0.33)

The light-emitting element using BBCz-R showed a relatively high value of 22% of the maximum external quantum efficiency. FWHM (Full Width at Half Maximum) representing the width of the emission spectrum is a narrow value of 26 nm. The chromaticity coordinates in the CIE (Commission Internationale de l'Eclairage) xy chromaticity diagram of the International Commission on Illumination are (0.67, 0.33), showing a color close to pure red.

As above, higher luminescent characteristics can be obtained by the luminescent material composed of the compound represented by formula (I).

none

[ Fig. 1 ] is a graph showing an example of the PL spectrum of the luminescent material of the present invention. [ Fig. 2] Fig. 2 is a graph showing an example of the current density-external quantum efficiency characteristic of the light-emitting device of the present invention. [ Fig. 3] Fig. 3 is a graph showing an example of voltage-current density characteristics of the light-emitting device of the present invention.

Claims (6)

A compound represented by formula (I),

In formula (I), R ¹ , R ² , R ³ , R ⁴ , R ⁵ and R ⁶ are independently substituted or unsubstituted alkyl groups, and m is independently any integer from 0 to 4, n is independently any integer from 0 to 3, Y is NR ⁷ , O or S, Z is NR ⁸ , O or S, R ⁷ and R ⁸ are independently a hydrogen atom, substituted or unsubstituted Alkyl or a substituted or unsubstituted aryl group, when ^R7 is a substituted or unsubstituted aryl group, the aryl group can be connected to the A1 ring to form a condensed ring, and ^R8 is substituted or unsubstituted In the case of a substituted aryl group, the aryl group may link with the A2 ring to form a condensed ring. As the compound of claim 1, it is represented by formula (II),

In formula (II), R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁹ and R ¹⁰ are independently substituted or unsubstituted alkyl groups, and m are independently 0~ any integer of 4, and n are each independently any integer of 0 to 3. The compound as claimed in claim 1, wherein the substituted or unsubstituted aryl in R ^{and R} in formula (I) is substituted or unsubstituted phenyl or substituted or unsubstituted naphthalene base. The compound according to any one of claims 1 to 3, wherein, in formulas (I) and (II), R ¹ , R ² , R ³ , R ⁴ , R 5 , R ⁶ , R ⁷ , ^{R 8 ,} R ⁹ and R ¹⁰ are independently substituted or unsubstituted C1~6 alkyl groups. A luminescent material comprising the compound according to any one of claims 1-4. A light-emitting element, which contains the light-emitting material of Claim 5.

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