TW202018059A - Charge-transporting composition - Google Patents

Abstract

Provided, for example, is a charge-transporting composition including the aniline derivative shown in the formula that follows. (In the formula, Ph is a phenyl group.).

Description

Charge transport composition

The present invention relates to a charge transport composition.

The charge-transporting thin films used in organic electroluminescence (hereinafter also referred to as organic EL) devices may be colored, which reduces the color purity and color reproducibility of the organic EL devices. In recent years, high transmittance and transparency in the visible light region have been desired Excellent performance (Patent Document 1). In view of this, the present applicant has discovered a material for a wet process which suppresses coloration in the visible light region and gives a charge-transporting film excellent in transparency (Patent Documents 1 and 2).

On the other hand, in order to improve the performance of organic EL devices, various measures have been taken so far, and measures for adjusting the refractive index of the functional film used have been performed for the purpose of improving light extraction efficiency and the like. Specifically, considering the overall refractive index of the device or the refractive index of other adjacent members, an attempt is made to increase the efficiency of the device by using a hole injection layer or a hole transport layer with a relatively high or low refractive index (for example, a patent Literature 3, 4). As such, the refractive index is an important element in the design of the organic EL device, and the refractive index is also considered to be an important physical property value that should be considered in the material for organic EL devices. [Prior Technical Literature] [Patent Literature]

[Patent Literature 1] International Publication No. 2013/042623 [Patent Literature 2] International Publication No. 2008/032616 [Patent Literature 3] Japanese Special Table No. 2007-536718 [Patent Literature 4] Japanese Special Table No. 2017-501585

[Problems to be solved by the invention]

The present invention was completed in view of the foregoing circumstances, and its object is to provide a charge-transporting composition that provides a thin film with good charge-transporting properties, a low extinction coefficient (k), good transparency, and a high refractive index (n), which can achieve The thin film is applied to an organic EL device having excellent characteristics when used in a hole injection layer or the like. [Means to solve the problem]

The inventors have repeatedly concentrated on the review in order to achieve the aforementioned object, and found that it contains a specific structure of N, N, N', N'-tetrakis(carbazol-2-yl)-p-phenylenediamine in the molecule. The charge transporting composition of the aniline derivative has a lower extinction coefficient (k) and better transparency than the case of using a aniline derivative of a similar structure, which not only gives a charge transporting film with a high refractive index (n), but also The composition itself is also excellent in storage stability, and when this charge-transporting thin film is applied to a hole injection layer or the like, an organic EL device having excellent characteristics can be given, and the present invention has been completed.

[式中，各Ar互相獨立地係下述式(Ar1)～(Ar9)之任一者所示的基；

(式中，R¹ ～R²¹ 互相獨立地係氫原子、可被Z¹ 取代之碳數1～20的烷基、可被Z¹ 取代之碳數2～20的烯基、可被Z¹ 取代之碳數2～20的炔基、可被Z² 取代之碳數6～20的芳基或可被Z² 取代之碳數2～20的雜芳基， Z¹ 係鹵素原子、硝基、氰基、可被Z³ 取代之碳數6～20的芳基或可被Z³ 取代之碳數2～20的雜芳基， Z² 係鹵素原子、硝基、氰基、可被Z³ 取代之碳數1～20的烷基、可被Z³ 取代之碳數2～20的烯基或可被Z³ 取代之碳數2～20的炔基， Z³ 係鹵素原子、硝基或氰基)]。 2.如1之電荷輸送性組成物，其中Ar皆為相同之基。 3.如2之電荷輸送性組成物，其中Ar係式(Ar1)～(Ar5)之任一者所示的基。 4.如3之電荷輸送性組成物，其中Ar係式(Ar1)所示的基。 5.如1～4之任一項之電荷輸送性組成物，其進一步包含摻雜物。 6.如5之電荷輸送性組成物，其中前述摻雜物係芳基磺酸酯化合物。 7.一種電荷輸送性薄膜，其係使用如1～5之任一項之電荷輸送性組成物製作。 8.一種有機電致發光元件，其具備如7之電荷輸送性薄膜。 [發明的效果]Therefore, the present invention provides the following charge transporting composition. 1. A charge transporting composition comprising an aniline derivative represented by the following formula (1);

[In the formula, each Ar is independently a group represented by any one of the following formulas (Ar1) to (Ar9);

(Wherein, R ¹ ~ R ²¹ are each independently a hydrogen atom based, Z can be ^a substituted alkyl group of 1 to 20 carbon atoms, which may be substituted with Z ¹ of alkenyl having 2 to 20, Z ¹ may be Substituted C 2-20 alkynyl group, Z ² substituted C 6-20 aryl group or Z ² substituted C 2-20 heteroaryl group, Z ¹ is a halogen atom, nitro group , cyano, Z ³ may be substituted or an aryl group of carbon number of Z ³ may be substituted with a carbon number of 6 to 20 heteroaryl group having 2 to 20, Z ² based halogen atom, a nitro group, a cyano group, Z may be ³ substituted C 1-20 alkyl group, Z ² substituted C 2-20 alkenyl group or Z ³ substituted C 2-20 alkynyl group, Z ³ is a halogen atom, nitro group Or cyano)]. 2. The charge transporting composition of 1, wherein Ar is the same base. 3. The charge transporting composition according to 2, wherein Ar is a group represented by any one of formulas (Ar1) to (Ar5). 4. The charge transporting composition according to 3, wherein Ar is a group represented by formula (Ar1). 5. The charge transport composition according to any one of 1 to 4, which further contains a dopant. 6. The charge transporting composition according to 5, wherein the dopant is an arylsulfonate compound. 7. A charge-transporting film produced using the charge-transporting composition according to any one of 1 to 5. 8. An organic electroluminescence device comprising a charge transport film as in 7. [Effect of invention]

By using the charge-transporting composition of the present invention, compared with the case of using a composition containing an aniline derivative of a similar structure, a high transparency (low extinction coefficient (k)) and high refractive index (n) can be produced Charge transport film. In addition, the charge-transporting composition of the present invention is excellent in storage stability compared with a composition containing an aniline derivative having a similar structure. Furthermore, the charge-transporting thin film obtained from the charge-transporting composition of the present invention can be applied as a thin film for electronic devices including organic EL devices, by using it as a film provided between the anode of the organic EL device and the light-emitting layer The functional layer, especially the hole injection layer, can obtain an organic EL device having excellent characteristics.

[Forms for carrying out the invention] [Charge transport composition]

The charge transporting composition of the present invention contains an aniline derivative represented by the following formula (1).

In formula (1), each Ar is independently a group represented by any one of the following formulas (Ar1) to (Ar9).

In the formula (Ar1) ~ (Ar9), R 1 ~ R 21 are each independently a hydrogen atom based, Z can be ^a substituted alkyl group of 1 to 20 carbon atoms, Z may be ^a substituted alkenyl of 2 to 20 carbon atoms Group, C 2-20 alkynyl group which may be substituted by Z ¹ , C 6-20 aryl group which may be substituted by Z ² or C 2-20 heteroaryl group which may be substituted by Z ² ; Z ¹ Department halogen atom, a nitro group, a cyano group, Z ³ may be substituted or an aryl group of carbon number of Z ³ may be substituted with a carbon number of 6 to 20 heteroaryl group having 2 to 20; the Z ² based halogen atom, a nitro group, a cyano group, Z may be ^{3-substituted} alkyl of 1 to 20 carbon atoms, which may be substituted with Z ³ carbon atoms, an alkenyl group of 2 to 20, or Z ³ may be substituted with an alkynyl group having a carbon number of 2 to 20; Z ³ Department of halogen atoms, nitro or cyano.

Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. A fluorine atom is preferred.

The alkyl group having 1 to 20 carbon atoms may be linear, branched, or cyclic. Specific examples thereof include methyl, ethyl, n-propyl, isopropyl, and n-butyl. , Isobutyl, second butyl, third butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, etc., linear or branched with 1 to 20 carbon atoms Like alkyl; cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, etc. C3-20 cyclic alkyl group.

The alkenyl group having 2 to 20 carbon atoms may be linear, branched, or cyclic. Specific examples thereof include vinyl, n-1-propenyl, n-propenyl, and 1- Methyl vinyl, n-butenyl, n-butenyl, n-butenyl, 2-methyl-1-propenyl, 2-methyl-2-propenyl, 1-ethyl Vinyl, 1-methyl-1-propenyl, 1-methyl-2-propenyl, n-pentenyl, n-decenyl and the like.

The alkynyl group having 2 to 20 carbon atoms may be linear, branched, or cyclic. Specific examples thereof include ethynyl, n-propynyl, n-propynyl, N-butynyl, n-butynyl, n-butynyl, 1-methyl-2-propynyl, n-pentynyl, n-pentynyl, n-pentyl Alkynyl, n-4-pentynyl, 1-methyl-n-butynyl, 2-methyl-n-butynyl, 3-methyl-n-butynyl, 1,1-dimethyl-n-propynyl, n- 1-hexynyl, n-decynyl, etc.

Specific examples of the aryl group having 6 to 20 carbon atoms include phenyl, tolyl, 1-naphthyl, 2-naphthyl, 1-anthryl, 2-anthryl, 9-anthryl, 1- Phenyl, 2-phenanthrene, 3-phenanthrene, 4-phenanthrene, 9-phenanthrene, etc.

唑基、4-

唑基、5-

唑基、3-異

唑基、4-異

唑基、5-異

唑基等之含氧雜芳基、2-噻唑基、4-噻唑基、5-噻唑基、3-異噻唑基、4-異噻唑基、5-異噻唑基等之含硫雜芳基、2-咪唑基、4-咪唑基、2-吡啶基、3-吡啶基、4-吡啶基、2-吡唑基、3-吡唑基、5-吡唑基、6-吡唑基、2-嘧啶基、4-嘧啶基、5-嘧啶基、6-嘧啶基、3-嗒

基、4-嗒

基、5-嗒

基、6-嗒

基、1,2,3-三

-4-基、1,2,3-三

-5-基、1,2,4-三

-3-基、1,2,4-三

-5-基、1,2,4-三

-6-基、1,3,5-三

-2-基、1,2,4,5-四

-3-基、1,2,3,4-四

-5-基、2-喹啉基、3-喹啉基、4-喹啉基、5-喹啉基、6-喹啉基、7-喹啉基、8-喹啉基、1-異喹啉基、3-異喹啉基、4-異喹啉基、5-異喹啉基、6-異喹啉基、7-異喹啉基、8-異喹啉基、2-喹喔啉基、5-喹喔啉基、6-喹喔啉基、2-喹唑啉基、4-喹唑啉基、5-喹唑啉基、6-喹唑啉基、7-喹唑啉基、8-喹唑啉基、3-噌啉基、4-噌啉基、5-噌啉基、6-噌啉基、7-噌啉基、8-噌啉基等之含氮雜芳基等。Specific examples of the heteroaryl group having 2 to 20 carbon atoms include 2-thienyl, 3-thienyl, 2-furanyl, 3-furanyl, and 2-

Oxazolyl, 4-

Oxazolyl, 5-

Oxazolyl, 3-iso

Oxazolyl, 4-iso

Oxazolyl, 5-iso

Oxygen-containing heteroaryl groups such as oxazolyl, 2-thiazolyl, 4-thiazolyl, 5-thiazolyl, 3-isothiazolyl, 4-isothiazolyl, 5-isothiazolyl, etc. 2-imidazolyl, 4-imidazolyl, 2-pyridyl, 3-pyridyl, 4-pyridyl, 2-pyrazolyl, 3-pyrazolyl, 5-pyrazolyl, 6-pyrazolyl, 2 -Pyrimidinyl, 4-pyrimidinyl, 5-pyrimidinyl, 6-pyrimidinyl, 3-pyridine

Base, 4-tap

Base, 5-tap

Base, 6-click

Base, 1,2,3-three

-4-yl, 1,2,3-tri

-5-yl, 1,2,4-tri

-3-yl, 1,2,4-tri

-5-yl, 1,2,4-tri

-6-yl, 1,3,5-tri

-2-yl, 1,2,4,5-tetra

-3-yl, 1,2,3,4-four

-5-yl, 2-quinolyl, 3-quinolyl, 4-quinolyl, 5-quinolyl, 6-quinolyl, 7-quinolyl, 8-quinolyl, 1-iso Quinoline, 3-isoquinoline, 4-isoquinoline, 5-isoquinoline, 6-isoquinoline, 7-isoquinoline, 8-isoquinoline, 2-quinoline Porphyrinyl, 5-quinoxalinyl, 6-quinoxalinyl, 2-quinazolinyl, 4-quinazolinyl, 5-quinazolinyl, 6-quinazolinyl, 7-quinazolinyl Nitrogen-containing heteroaromatic groups such as alkyl, 8-quinazolinyl, 3-cinnolinyl, 4-cinnolinyl, 5-cinnolinyl, 6-cinnolinyl, 7-cinnolinyl, 8-cinnolinyl, etc. Base etc.

Wherein, as the R ¹ ~ R ^21, preferably Z ² carbon atoms which may be substituted with an aryl group of 6 to 20, Z ² may be substituted with a heteroaryl group having a carbon number of 2 to 20, more preferably Z ² may be a substituted aryl group having a carbon number of 6 to 20, particularly preferably Z ² may be substituted with the phenyl group which may be substituted with Z ² of the 1-naphthyl group, which may be substituted with Z ² of a 2-naphthyl group. Further, as Z ^2, it is preferably a halogen atom, an alkyl group Z ³ may be substituted with the 1 to 20 carbon atoms, which may be substituted with Z ³ carbon atoms, an alkenyl group of 2 to 20. Z ^{3 is} preferably a halogen atom, and more preferably a fluorine atom.

In the present invention, from the viewpoint of ease of synthesis of the aniline derivative, Ar is preferably all the same groups. In addition, from the viewpoint of improving the solubility of the aniline derivative in the organic solvent and obtaining a highly uniform composition with good reproducibility, the group represented by any one of formulas (Ar1) to (Ar5) is preferred , The best is the group represented by formula (Ar1).

(式中，Ph係苯基)。Specific examples of aniline derivatives suitable in the present invention are given below, but not limited thereto.

(In the formula, Ph is phenyl).

The aniline derivative used in the present invention can be obtained by the presence of a catalyst, the p-phenylenediamine (1,4-phenylenediamine) and the halogenated or pseudo-halogenated carbazole derivative Ar-X (Ar is the same as above ; X series halogen atoms or pseudo-halogen groups) reaction and manufacturing.

Examples of the halogen atom include the same as described above, and a chlorine atom, a bromine atom, and an iodine atom are preferred. Examples of the pseudo-halogen group include (fluoro)alkylsulfonyloxy groups such as methanesulfonyloxy, trifluoromethanesulfonyloxy, nonafluorobutanesulfonyloxy; benzenesulfonyloxy, toluene Aromatic sulfonyloxy, etc.

The feed ratio of 1,4-phenylenediamine to halogenated or pseudo-halogenated carbazole derivatives is relative to the mass of all NH groups of 1,4-phenylenediamine. The halogenated or pseudo-halogenated carbazole derivatives can be set It is more than equivalent, but is preferably about 1 to 1.2 equivalent.

Examples of the catalyst used in the foregoing reaction include copper catalysts such as copper chloride, copper bromide, and copper iodide; tetrakis(triphenylphosphine)palladium (Pd(PPh ₃ ) ₄ ) and bis(triphenylbenzene Phosphine) dichloropalladium (Pd(PPh ₃ ) ₂ Cl ₂ ), bis(dibenzylideneacetone) palladium (Pd(dba) ₂ ), ginseng (dibenzylideneacetone) dipalladium (Pd ₂ (dba) ₃ ) Palladium catalysts such as bis[tris(third butylphosphine)] palladium (Pd(Pt-Bu ₃ ) ₂ ), palladium acetate (Pd(OAc) ₂ ), etc. These catalysts can be used alone or in combination of two or more.

Moreover, these catalysts can also be used with well-known suitable ligands. Examples of such a ligand include triphenylphosphine, tri-o-tolylphosphine, diphenylmethylphosphine, phenyldimethylphosphine, trimethylphosphine, triethylphosphine, tributylphosphine, Tri-tert-butylphosphine, di-tert-butyl(phenyl)phosphine, di-tert-butyl(4-dimethylaminophenyl)phosphine, 1,2-bis(diphenylphosphino)ethane , 1,3-bis (diphenylphosphino) propane, 1,4-bis (diphenylphosphino) butane, 1,1'-bis (diphenylphosphino) ferrocene and other tertiary Tertiary phosphites such as phosphine, phosphorous triformate, triethyl phosphite, triphenyl phosphite, etc.

The use amount of the catalyst is about 0.01 to 0.2 mol, preferably about 0.15 mol, relative to 1 mol of the halogenated or pseudo-halogenated carbazole derivative. In addition, when a ligand is used, the amount of the catalyst used may be 0.1 to 5 equivalents, preferably 1 to 2 equivalents.

烷、1,2-二甲氧基乙烷、1,2-二乙氧基乙烷等)、酮類(丙酮、甲基乙基酮、甲基異丁基酮、二正丁基酮、環己酮等)、醯胺類(N,N-二甲基甲醯胺、N,N-二甲基乙醯胺等)、內醯胺及內酯類(N-甲基吡咯啶酮、γ-丁內酯等)、尿素類(N,N-二甲基咪唑啉酮、四甲基脲等)、亞碸類(二甲亞碸、環丁碸等)、腈類(乙腈、丙腈、丁腈等)等，惟不受此等所限定。此等之溶劑係可單獨1種使用，也可組合2種以上使用。When all the raw material compounds are solid or from the viewpoint of efficiently obtaining the intended aniline derivative, the aforementioned reactions are carried out in a solvent. When a solvent is used, its type is not particularly limited as long as it does not adversely affect the reaction. Specific examples include aliphatic hydrocarbons (pentane, n-hexane, n-octane, n-decane, decahydronaphthalene, etc.), halogenated aliphatic hydrocarbons (chloroform, methylene chloride, dichloroethane, tetrachloroethane Carbon chloride, etc.), aromatic hydrocarbons (benzene, nitrobenzene, toluene, o-xylene, m-xylene, p-xylene, mesitylene, etc.), halogenated aromatic hydrocarbons (chlorobenzene, bromobenzene, o Dichlorobenzene, m-dichlorobenzene, p-dichlorobenzene, etc.), ethers (diethyl ether, diisopropyl ether, third butyl methyl ether, tetrahydrofuran, di

Alkane, 1,2-dimethoxyethane, 1,2-diethoxyethane, etc.), ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, di-n-butyl ketone, (Cyclohexanone, etc.), amides (N,N-dimethylformamide, N,N-dimethylacetamide, etc.), lactamides and lactones (N-methylpyrrolidone, γ-butyrolactone, etc.), urea (N,N-dimethylimidazolidinone, tetramethylurea, etc.), sulfonate (dimethyl sulfonate, cyclobutane, etc.), nitriles (acetonitrile, propylene Nitrile, butyronitrile, etc.), but not limited by these. These solvent systems may be used alone or in combination of two or more.

The reaction temperature may be appropriately set in the range from the melting point to the boiling point of the solvent used, and it is usually in the range of about 0 to 200°C, preferably in the range of 20 to 150°C. After the reaction, the post-treatment can be performed according to common methods to obtain the target aniline derivative.

The charge transport composition of the present invention contains an organic solvent. As such an organic solvent, a highly soluble solvent that can dissolve an aniline derivative represented by formula (1) of a charge transporting substance well can be used. Specific examples of highly soluble solvents include, for example, cyclohexanone, N,N-dimethylformamide, N,N-dimethylacetamide, and N,N-dimethylisobutylamide. Organic solvents such as amines, N-methylpyrrolidone, 1,3-dimethyl-2-imidazolidinone, diethylene glycol monomethyl ether, etc., are not limited thereto. These solvent systems may be used alone or in combination of two or more. The use amount may be 5 to 100% by mass relative to the entire solvent used in the composition.

In addition, since the composition contains at least one species, it has a viscosity of 10 to 200 mPa·s at 25°C, especially 35 to 150 mPa·s, and a boiling point of 50 to 300°C, especially 150 to 250°C at normal pressure (atmospheric pressure). The high-viscosity organic solvent makes it easy to adjust the viscosity of the composition. As a result, the film with high flatness can be given with good reproducibility, and the composition can be adjusted according to the coating method used. Examples of high-viscosity organic solvents include cyclohexanol, ethylene glycol, ethylene glycol diglycidyl ether, 1,3-octanediol, diethylene glycol, dipropylene glycol, triethylene glycol, and triethylene glycol. Propylene glycol, 1,3-butanediol, 2,3-butanediol, 1,4-butanediol, propylene glycol, hexanediol, etc., but not limited by these. These solvent systems may be used alone or in combination of two or more. The addition ratio of the high-viscosity organic solvent is preferably within a range where solids do not precipitate with respect to the entire solvent used for the composition, and within a range where solids do not precipitate, the addition ratio is preferably 5 to 80% by mass.

Furthermore, for the purpose of improving the wettability to the substrate, adjusting the surface tension of the solvent, adjusting the polarity, adjusting the boiling point, etc., it may be 1 to 90% by mass, preferably 1 to 50, relative to the total solvent used in the composition The ratio of mass% is mixed with other solvents. Examples of such solvents include propylene glycol monomethyl ether, ethylene glycol monobutyl ether, diethylene glycol diethyl ether, diethylene glycol dimethyl ether, and diethylene glycol monoethyl ether. Ester, diethylene glycol monobutyl ether acetate, dipropylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether, diacetone alcohol, γ-butyrolactone, Ethyl lactate, n-hexyl acetate, etc., are not limited by these. These solvent systems may be used alone or in combination of two or more.

烷、苯甲醚、4-甲氧基甲苯、3-苯氧基甲苯、二苄基醚、二乙二醇二甲基醚、二乙二醇丁基甲基醚、三乙二醇二甲基醚、三乙二醇丁基甲基醚等之醚系溶劑；苯甲酸甲酯、苯甲酸乙酯、苯甲酸丁酯、鄰苯二甲酸二甲酯、馬來酸二乙酯、苯甲酸異戊酯、鄰苯二甲酸雙(2-乙基己基)酯、馬來酸二丁酯、草酸二丁酯、乙酸己酯、二乙二醇單乙基醚乙酸酯、二乙二醇單丁基醚乙酸酯等之酯系溶劑等，惟不受此等所限定。此等之溶劑係可單獨1種使用，也可組合2種以上使用。In addition, the aniline derivative represented by the formula (1), for example, as in the case where it has an aryl group on the 9-position nitrogen atom of the carbazole site in the molecule, has an substituent on at least one nitrogen atom in the molecule When it is preferable to have a substituent on all nitrogen atoms, it is easy to prepare a composition using only a low-polar solvent. Specific examples of such low-polarity solvents include chlorine-based solvents such as chloroform and chlorobenzene; aromatic hydrocarbon-based solvents such as toluene, xylene, tetrahydronaphthalene, cyclohexylbenzene, and decylbenzene; 1-octyl Aliphatic alcohol solvents such as alcohol, 1-nonanol, 1-decanol, etc.; tetrahydrofuran, di

Alkanes, anisole, 4-methoxytoluene, 3-phenoxytoluene, dibenzyl ether, diethylene glycol dimethyl ether, diethylene glycol butyl methyl ether, triethylene glycol dimethyl ether , Triethylene glycol butyl methyl ether and other ether solvents; methyl benzoate, ethyl benzoate, butyl benzoate, dimethyl phthalate, diethyl maleate, isoamyl benzoate, Bis(2-ethylhexyl) phthalate, dibutyl maleate, dibutyl oxalate, hexyl acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether Ester-based solvents such as acetates are not limited to these. These solvent systems may be used alone or in combination of two or more.

Although the charge-transporting composition of the present invention may contain water as a solvent, when the charge-transporting thin film obtained from the composition is used as a hole injection layer of an organic EL element, high durability can be obtained with good reproducibility. From the viewpoint of the device, the content of water is preferably 10% by mass or less of the entire solvent, more preferably 5% by mass or less, and most preferably, only an organic solvent is used as the solvent. In addition, "organic solvent only" in this case means that the user of the solvent is only an organic solvent, and it does not deny the presence of "water" contained in trace amounts in the organic solvent or solid content used. In addition, in the present invention, the solid content means a component other than the solvent contained in the charge transport composition.

The charge-transporting composition of the present invention may include a charge-transporting substance composed of an aniline derivative represented by formula (1), as well as other charge-transporting substances.

The charge-transporting composition of the present invention contains a charge-transporting substance composed of an aniline derivative represented by formula (1) and an organic solvent. However, according to the use of the obtained film, the purpose is to improve the charge-transporting ability and the like. Dopants (charge-receiving substances) may be included.

The dopant is not particularly limited as long as it is dissolved in at least one solvent used in the composition, and any of inorganic dopants and organic dopants can be used. In addition, the inorganic and organic dopant systems may be used alone or in combination of two or more. In addition, in the process of obtaining a charge-transporting thin film of a solid film from the composition, for example, by external stimulation such as heating during firing, a part of the molecule is detached, and the function of the dopant begins to develop Or the elevated substance may be, for example, an arylsulfonate compound protected by a sulfonic acid group that is easily detached.

The amount of the dopant substance in the composition varies depending on the desired degree of charge transportability or the type of the dopant substance, and cannot be specified in general, but it is usually derived from the aniline represented by formula (1) Object 1, expressed as a mass ratio, is in the range of 0.0001 to 100.

In the present invention, examples of preferred inorganic dopants include heteropolyacids. The so-called heteropoly acid is typically represented by the chemical structure of the Keggin type represented by the following formula (H1) or the Dawson type represented by the following formula (H2), and has a structure in which the heteroatom is located at the center of the molecule, vanadium ( V), polyacid of molybdenum (Mo), tungsten (W) and other oxoacids and polyoxocondensation of oxoacids of different elements. As such oxyacids of different elements, oxyacids of silicon (Si), phosphorus (P), and arsenic (As) are mainly mentioned.

Specific examples of the heteropoly acid include phosphomolybdic acid, silicomolybdic acid, phosphotungstic acid, silicotungstic acid, phosphotungstic molybdic acid, and the like. These heteropoly acids can be used alone or in combination of two or more. In addition, these heteropoly acids can be obtained as commercial products, and can also be synthesized by well-known methods.

In particular, when one type of heteropolyacid is used, the one type of heteropolyacid is preferably phosphotungstic acid or phosphomolybdic acid, and most preferably phosphotungstic acid. In addition, when two or more types of heteropolyacids are used, one of the two or more types of heteropolyacid is preferably phosphotungstic acid or phosphomolybdic acid, more preferably phosphotungstic acid.

In addition, the heteropolyacid is used in quantitative analysis such as elemental analysis, and according to the structure represented by the general formula, even if the number of elements is large or small, as long as it is obtained as a commercially available product, or according to a well-known synthesis method Those synthesized appropriately can be used in the present invention. That is, for example, in general, phosphotungstic acid is represented by the chemical formula H ₃ (PW ₁₂ O ₄₀ )·nH ₂ O, and phosphomolybdic acid is represented by the chemical formula H ₃ (PMo ₁₂ O ₄₀ )·nH ₂ O, but in quantitative In the analysis, even if the number of P (phosphorus), O (oxygen), W (tungsten) or Mo (molybdenum) in this formula is more or less, as long as it is obtained as a commercial product, or according to well-known synthesis If the method is properly synthesized, it can be used in the present invention. At this time, the quality of the heteropoly acid specified in the present invention is not the quality of the pure phosphotungstic acid (phosphotungstic acid content) in the composition or the commercial product, but means the form and the form available as a commercial product. In a form that can be separated by a well-known synthesis method, it contains the total mass in the state of hydrated water or other impurities.

When heteropolyacid is used as a dopant, the amount of aniline derivative 1 represented by formula (1) is expressed in terms of mass ratio, and its use amount may be about 0.001 to 50.0, preferably about 0.01 to 20.0, more preferably It is about 0.1 to 10.0.

In addition, as a preferred organic-based dopant, a tetracyanoquinodimethane derivative or a benzoquinone derivative may be mentioned. Specific examples of tetracyanoquinodimethane derivatives include 7,7,8,8-tetracyanoquinodimethane (TCNQ) or halogenated tetracyanoquinodimethane represented by the following formula (H3), etc. . In addition, specific examples of the benzoquinone derivatives include tetrafluoro-1,4-benzoquinone (F4BQ), tetrachloro-1,4-benzoquinone (tetrachlorobenzoquinone), and tetrabromo-1,4- Benzoquinone, 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), etc.

In formula (H3), R ¹⁰¹ to R ¹⁰⁴ independently represent a hydrogen atom or a halogen atom, at least one is a halogen atom, preferably at least two are halogen atoms, more preferably at least three are halogen atoms, and most preferably all are Halogen atom. The halogen atom may be the same as described above, preferably a fluorine atom or a chlorine atom, and more preferably a fluorine atom.

Examples of such halogenated tetracyanoquinodimethane include 2-fluoro-7,7,8,8-tetracyanoquinodimethane and 2-chloro-7,7,8,8-tetracyano Quinoquinodimethane, 2,5-difluoro-7,7,8,8-tetracyanoquinodimethane, 2,5-dichloro-7,7,8,8-tetracyanoquinodimethane, 2 ,3,5,6-tetrachloro-7,7,8,8-tetracyanoquinodimethane, 2,3,5,6-tetrafluoro-7,7,8,8 tetracyanoquinodimethane ( F4TCNQ) etc.

When a tetracyanoquinodimethane derivative or a benzoquinone derivative is used as a dopant, relative to the aniline derivative 1 represented by formula (1), the amount of use can be 0.01 in terms of mass ratio (mole) It is about 20.0, preferably about 0.1 to 10.0, and more preferably about 0.5 to 5.0.

烷二磺酸化合物、國際公開第2006/025342號記載的芳基磺酸化合物、國際公開第2009/096352號記載的芳基磺酸化合物等。In addition, as other preferred organic-based dopants, arylsulfonic acid compounds may be mentioned. Specific examples thereof include benzenesulfonic acid, toluenesulfonic acid, p-styrenesulfonic acid, 2-naphthalenesulfonic acid, 4-hydroxybenzenesulfonic acid, 5-sulfosalicylic acid, and p-dodecylbenzenesulfonic acid. , Dihexylbenzenesulfonic acid, 2,5-dihexylbenzenesulfonic acid, dibutylnaphthalenesulfonic acid, 6,7-dibutyl-2-p-naphthalenesulfonic acid, dodecylnaphthalenesulfonic acid, 3-dodecyl 2-naphthalenesulfonic acid, hexylnaphthalenesulfonic acid, 4-hexyl-1-naphthalenesulfonic acid, octylnaphthalenesulfonic acid, 2-octyl-1-naphthalenesulfonic acid, hexylnaphthalenesulfonic acid, 7-hexyl-1 -Naphthalenesulfonic acid, 6-hexyl-2-naphthalenesulfonic acid, dinonylnaphthalenesulfonic acid, 2,7-dinonyl-4-naphthalenesulfonic acid, dinonylnaphthalene disulfonic acid, 2,7-dinonyl -4,5-naphthalenedisulfonic acid, 1,4-benzodiene described in International Publication No. 2005/000832

Alkanedisulfonic acid compounds, arylsulfonic acid compounds described in International Publication No. 2006/025342, arylsulfonic acid compounds described in International Publication No. 2009/096352, and the like.

More specifically, an arylsulfonic acid compound represented by the following formula (H4) or (H5) can be mentioned.

In formula (H4), A ¹ represents O or S, preferably O. A ² is a (q+1)-valent group derived from naphthalene or anthracene (that is, a group obtained by removing (q+1) hydrogen atoms from naphthalene or anthracene), but is preferably derived from naphthalene. A ³ is a p-valent group derived from perfluorobiphenyl (ie, a group obtained by removing p fluorine atoms from perfluorobiphenyl). p represents the number of bonds between A ¹ and A ³ and is an integer satisfying 2≦p≦4, preferably 2. At this time, A ³ is perfluorobiphenyldiyl, preferably perfluorobiphenyl-4,4′-diyl. q represents the number of sulfonic acid groups bonded to A ² , and is an integer that satisfies 1≦q≦4, and is optimally 2.

In formula (H5), A ⁴ to A ^{8 are} independently a hydrogen atom, a halogen atom, a cyano group, a C 1-20 alkyl group, a C 1-20 halogenated alkyl group, or a C 2-20 halogenated Alkenyl, but at least three of A ⁴ to A ⁸ are halogen atoms.

Examples of the halogenated alkyl group having 1 to 20 carbon atoms include trifluoromethyl, 2,2,2-trifluoroethyl, 1,1,2,2,2-pentafluoroethyl, 3,3,3 -Trifluoropropyl, 2,2,3,3,3-pentafluoropropyl, 1,1,2,2,3,3,3-heptafluoropropyl, 4,4,4-trifluorobutyl , 3,3,4,4,4-pentafluorobutyl, 2,2,3,3,4,4,4-heptafluorobutyl, 1,1,2,2,3,3,4,4 , 4-nonafluorobutyl, etc. Examples of the halogenated alkenyl group having 2 to 20 carbon atoms include perfluorovinyl, perfluoro-1-propenyl, perfluoro-2-propenyl, and perfluorobutenyl. In addition, examples of the halogen atom and the alkyl group having 1 to 20 carbon atoms include the same as described above, but the halogen atom is preferably a fluorine atom.

Among these, A ⁴ to A ^{8 are} preferably a hydrogen atom, a halogen atom, a cyano group, a C 1-10 alkyl group, a C 1-10 halogenated alkyl group or a C 2-10 halogenated alkylene Group, and at least 3 of A ⁴ to A ⁸ are fluorine atoms, more preferably hydrogen atom, fluorine atom, cyano group, C 1-5 alkyl group, C 1-5 fluorinated alkyl group or carbon A fluorinated alkenyl group having 2 to 5 atoms, and at least 3 of A ⁴ to A ⁸ are fluorine atoms, particularly preferably a hydrogen atom, a fluorine atom, a cyano group, a C 1-5 perfluoroalkyl group or a carbon number 1 to 5 perfluoroalkenyl groups, and A ⁴ , A ⁵ and A ⁸ are fluorine atoms. In addition, the so-called perfluoroalkyl group is a group in which the hydrogen atoms of the alkyl group are all replaced by fluorine atoms, and the so-called perfluoroalkenyl group is a group in which the hydrogen atoms of the alkenyl group are completely replaced by fluorine atoms.

In formula (H5), r represents the number of sulfonic acid groups bonded to the naphthalene ring, and is an integer satisfying 1≦r≦4, preferably 2 to 4, and most preferably 2.

Specific examples of suitable arylsulfonic acid compounds are given below, but are not limited thereto.

When an arylsulfonic acid compound is used as a dopant, relative to the aniline derivative 1 represented by the formula (1), the amount of use is expressed in terms of mass (mole) ratio, and the amount used is preferably about 0.01 to 20.0, and more preferably Around 0.4 to 5.0. The arylsulfonic acid compound can be a commercially available product, or can be synthesized by a well-known method described in International Publication No. 2006/025342, International Publication No. 2009/096352, and the like.

In addition, as other preferred organic-based dopants, arylsulfonate compounds may be mentioned. Specific examples thereof include the arylsulfonate compound disclosed in International Publication No. 2017/217455, and the arylsulfonate compound disclosed in International Publication No. 2017/217457.

More specifically, the arylsulfonate compound is preferably represented by any one of the following formulas (H6) to (H8).

In formulas (H6) to (H8), m is an integer that satisfies 1≦m≦4, preferably 2. n is an integer satisfying 1≦n≦4, preferably 2.

In formula (H6), A ¹¹ is an m-valent group derived from perfluorobiphenyl. A ¹² is -O- or -S-, preferably -O-. A ¹³ is a (n+1)-valent group derived from naphthalene or anthracene, preferably derived from naphthalene.

R ^s1 to R ^{s4 are} independently a hydrogen atom, or a linear or branched C 1-6 alkyl group, and R ^s5 is a C ^2-20 monovalent hydrocarbon group which may be substituted. Examples of the linear or branched C 1-6 alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, second butyl, and third Butyl, n-hexyl, etc. Among these, alkyl groups having 1 to 3 carbon atoms are preferred. The monovalent hydrocarbon group having 2 to 20 carbon atoms may be linear, branched, or cyclic. Specific examples thereof include ethyl, n-propyl, isopropyl, n-butyl, and iso Alkyl groups such as butyl and tertiary butyl; aryl groups such as phenyl, naphthyl and phenanthrenyl.

In particular, among R ^s1 to R ^s4 , it is preferred that R ^s1 or R ^s3 is a linear alkyl group having 1 to 3 carbon atoms, and the remainder is a hydrogen atom, or R ^s1 is a linear alkyl group having 1 to 3 carbon atoms. , R ^s2 to R ^s4 are hydrogen atoms. In this case, the linear alkyl group having 1 to 3 carbon atoms is preferably a methyl group. Moreover, R ^{s5 is} preferably a linear alkyl group having 2 to 4 carbon atoms or a phenyl group.

In the formula (H7), A ¹⁴ is a m-valent hydrocarbon group having 6 to 20 carbon atoms which may be substituted with one or more aromatic rings, and this hydrocarbon group has a carbon number of 6 to 20 which contains one or more aromatic rings. A hydrocarbon compound is obtained by removing m hydrogen atoms. Examples of such hydrocarbon compounds include benzene, toluene, xylene, ethylbenzene, biphenyl, naphthalene, anthracene, and phenanthrene. In addition, some or all of the hydrogen atoms of the aforementioned hydrocarbon groups may be further substituted with substituents. Examples of such substituents include fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, nitro groups, cyano groups, and hydroxyl groups. Amino group, silanol group, thiol group, carboxyl group, sulfonate group, phosphoric acid group, phosphoric acid ester group, ester group, thioester group, amide group, monovalent hydrocarbon group, organic oxygen group, organic amine group, organic silicon Group, organic sulfur group, acetyl group, sulfo group, etc. Among these, A ^{14 is} preferably a group derived from benzene, biphenyl, or the like.

In formula (H7), A ¹⁵ is -O- or -S-, preferably -O-.

In formula (H7), A ¹⁶ is a (n+1)-valent aromatic hydrocarbon group having 6 to 20 carbon atoms, and this aromatic hydrocarbon group is removed from the aromatic ring of an aromatic hydrocarbon compound having 6 to 20 carbon atoms (n+ 1) A base derived from hydrogen atoms. Examples of such aromatic hydrocarbon compounds include benzene, toluene, xylene, biphenyl, naphthalene, anthracene, and pyrene. Among them, A ^{16 is} preferably a group derived from naphthalene or anthracene, and more preferably a group derived from naphthalene.

In formula (H7), R ^s6 and R ^{s7 are} independently a hydrogen atom, or a linear or branched monovalent aliphatic hydrocarbon group, and R ^s8 is a linear or branched monovalent aliphatic hydrocarbon group. However, the total carbon number of R ^s6 , R ^s7 and R ^s8 is 6 or more. The upper limit of the total carbon number of R ^s6 , R ^s7 and R ^s8 is not particularly limited, but it is preferably 20 or less, and more preferably 10 or less. Specific examples of the linear or branched monovalent aliphatic hydrocarbon group include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, second butyl, and third C1-C20 alkyl groups such as butyl, n-hexyl, n-octyl, 2-ethylhexyl, and decyl; vinyl, 1-propenyl, 2-propenyl, isopropenyl, 1-methyl C2-C20 alkenyl groups such as 2-propenyl, 1-butenyl, 2-butenyl, 3-butenyl, hexenyl, etc. Among these, R ^{s6 is} preferably a hydrogen atom, and R ^s7 and R ^{s8 are} independently of each other preferably a C 1-6 alkyl group.

In formula (H8), R ^s9 to R ^{s13 are} independently a hydrogen atom, a nitro group, a cyano group, a halogen atom, a C 1-10 alkyl group, a C 1-10 halogenated alkyl group, or a C 2 to C 2 10 halogenated alkenyl.

The C1-C10 alkyl group may be linear, branched, or cyclic. Specific examples thereof include methyl, ethyl, n-propyl, isopropyl, and n-butyl. , Isobutyl, second butyl, third butyl, n-pentyl, cyclopentyl, n-hexyl, cyclohexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, etc.

The halogenated alkyl group having 1 to 10 carbon atoms is not particularly limited as long as part or all of the hydrogen atoms of the alkyl group having 1 to 10 carbon atoms are substituted with halogen atoms. Specific examples thereof include trifluoromethyl, 2,2,2-trifluoroethyl, 1,1,2,2,2-pentafluoroethyl, 3,3,3-trifluoropropyl, 2,2,3,3,3-pentafluoropropyl, 1,1,2,2,3,3,3-heptafluoropropyl, 4,4,4-trifluorobutyl, 3,3,4 ,4,4-pentafluorobutyl, 2,2,3,3,4,4,4-heptafluorobutyl, 1,1,2,2,3,3,4,4,4-nonafluorobutane Base etc.

The halogenated alkenyl group having 2 to 10 carbon atoms is not particularly limited as long as a part or all of the hydrogen atoms of the alkenyl group having 2 to 10 carbon atoms are substituted with halogen atoms. Specific examples thereof include perfluorovinyl, perfluoro-1-propenyl, perfluoro-2-propenyl, perfluoro-1-butenyl, perfluoro-2-butenyl, and perfluoro- 3-butenyl, etc.

Among these, R ^{s9 is} preferably a nitro group, a cyano group, a halogenated alkyl group having 1 to 10 carbon atoms, a halogenated alkenyl group having 2 to 10 carbon atoms, more preferably a nitro group, a cyano group, or a carbon number Halogenated alkyl groups of 1 to 4 and halogenated alkenyl groups of 2 to 4 carbon atoms are particularly preferably nitro, cyano, trifluoromethyl, and perfluoropropenyl.

In formula (H8), R ^s10 to R ^{s13 are} preferably a halogen atom, and more preferably a fluorine atom.

In formula (H8), A ¹⁷ is -O-, -S- or -NH-, preferably -O-.

In formula (H8), A ¹⁸ is a (n+1)-valent aromatic hydrocarbon group having 6 to 20 carbon atoms, and this aromatic hydrocarbon group is removed from the aromatic ring of an aromatic hydrocarbon compound having 6 to 20 carbon atoms (n+ 1) A base derived from hydrogen atoms. Examples of such aromatic hydrocarbon compounds include benzene, toluene, xylene, biphenyl, naphthalene, anthracene, and pyrene. Among these, as A ¹⁸ , a group derived from naphthalene or anthracene is preferred, and a group derived from naphthalene is preferred.

In the formula ^{(H8), R s14 ~ R} s17 each independently a hydrogen atom-based, or a linear or branched carbon atoms of the monovalent aliphatic hydrocarbon group having 1 to 20. Specific examples of the monovalent aliphatic hydrocarbon group include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, second butyl, third butyl, n-pentyl, and cyclo C1-C20 alkyl groups such as pentyl, n-hexyl, cyclohexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, and n-dodecyl; vinyl, 1- The carbon number of propenyl, 2-propenyl, isopropenyl, 1-methyl-2-propenyl, 1-butenyl, 2-butenyl, 3-butenyl, hexenyl, etc. is 2-20 Alkenyl etc. Among them, alkyl groups having 1 to 20 carbon atoms are preferred, alkyl groups having 1 to 10 carbon atoms are more preferred, and alkyl groups having 1 to 8 carbon atoms are particularly preferred.

In formula (H8), R ^s18 is a linear or branched monovalent aliphatic hydrocarbon group having 1 to 20 carbon atoms or OR ^s19 . R ^s19 is a monovalent hydrocarbon group having 2 to 20 carbon atoms which can be substituted. Examples of the linear or branched monovalent aliphatic hydrocarbon group having 1 to 20 carbon atoms represented by R ^s18 include the same as described above. When R ^s18 is a monovalent aliphatic hydrocarbon group, R ^{s18 is} preferably an alkyl group having 1 to 20 carbon atoms, more preferably an alkyl group having 1 to 10 carbon atoms, and particularly preferably an alkyl group having 1 to 8 carbon atoms. ^Examples of the C ^2-20 monovalent hydrocarbon group represented by R ^{s19 include} , in addition to the methyl group in the monovalent aliphatic hydrocarbon group, aryl groups such as phenyl, naphthyl, and phenanthryl. Among these, R ^{s19 is} preferably a linear alkyl group having 2 to 4 carbon atoms or a phenyl group. In addition, examples of the substituent that the monovalent hydrocarbon group may have include a fluorine atom, a C 1-4 alkoxy group, a nitro group, and a cyano group.

Specific examples of suitable arylsulfonate compounds include those shown below, but are not limited thereto.

When an aryl sulfonate compound is used as a dopant, it is expressed in terms of mass ratio (mole), and its use amount can be about 0.01 to 20.0 relative to the aniline derivative 1 represented by formula (1), preferably About 0.1 to 10.0, more preferably about 0.5 to 5.0.

When an organic dopant is used as the dopant, the molecular weight system is not particularly limited, but when used together with the aniline derivative represented by formula (1), good solubility and reproducibility in organic solvents are ensured From the viewpoint of obtaining a composition with high uniformity well, it is preferably 5,000 or less, more preferably 3,000 or less, and particularly preferably 2,000 or less. In particular, the molecular weight of the arylsulfonic acid compound used as the dopant is preferably 2,000 or less, and more preferably 1,500 or less from the same viewpoint.

In the present invention, in consideration of obtaining a thin film with high charge transportability with good reproducibility, the ease of obtaining a dopant, etc., as the dopant, it is preferable to use an arylsulfonic acid compound, an arylsulfonic acid ester compound, At least one kind of halogenated tetracyanoquinodimethane and benzoquinone derivatives, and it is more preferable to use an arylsulfonic acid compound and an arylsulfonic acid ester compound in consideration of obtaining a transparent charge-transporting film with good reproducibility. At least one kind, and when it is more considered to obtain a charge-transporting composition excellent in stability, it is particularly preferable to use an arylsulfonate compound.

The charge transporting substance and the dopant are preferably completely dissolved in the solvent or uniformly dispersed, and most preferably are completely dissolved.

The charge transporting composition of the present invention may contain an organosilane compound for the purpose of improving the injection property into the hole transporting layer when the obtained thin film is used as the hole injection layer of the organic EL device, improving the life characteristics of the device, etc. Or a nonionic fluorine-containing surfactant, its content is usually about 1 to 30 parts by mass relative to 100 parts by mass of the total charge transporting substance and dopant.

The solid content concentration in the charge-transporting composition of the present invention is generally about 0.1 to 20% by mass, preferably 0.5 to 15 from the viewpoint of ensuring a sufficient film thickness while suppressing the precipitation of the charge-transporting substance. quality%.

The viscosity of the charge transporting composition of the present invention is usually 1 to 50 mPa·s at 25°C, and the surface tension is usually 20 to 50 mN/m at 25°C. The viscosity and surface tension of the charge-transporting composition of the present invention can be adjusted in consideration of various factors such as the coating method used, the desired film thickness, etc., and the types of organic solvents used or their ratios, solid content concentrations, etc. can be adjusted .

The charge transporting composition of the present invention can be produced by dissolving the aniline derivative represented by formula (1) in an organic solvent. The aforementioned aniline derivative may be dissolved in an organic solvent in advance, other organic solvents may be sequentially added thereto, a mixed solvent of all solvents may be prepared in advance, and the aforementioned aniline derivative may be dissolved therein. In addition, if necessary, care can be taken to prevent the components contained in the composition from decomposing or deteriorating, and heating to promote the dissolution of the aniline derivative and the like. When the charge transporting composition of the present invention contains the components other than the aniline derivative and the solvent, the same method is used. In addition, the charge-transporting composition of the present invention can be obtained by dissolving the charge-transporting substance in an organic solvent from the viewpoint of obtaining a flat film with higher reproducibility, using a sub-micron filter or the like filter.

[Charge Transport Film] By applying the charge-transporting composition of the present invention to a substrate and firing it, a charge-transporting thin film can be formed on the substrate.

The coating method of the composition is not particularly limited, and examples thereof include a dipping method, a spin coating method, a transfer printing method, a roll coating method, an inkjet method, a spray method, and a slit coating method. Preferably, the viscosity and surface tension of the composition are adjusted according to the coating method.

The firing environment is also not particularly limited. Not only in an atmospheric environment (under air) but also in an inert gas such as nitrogen or vacuum, a thin film with a uniform film-forming surface and charge-transporting properties can also be obtained, but usually in an atmospheric environment Fired.

In addition, the firing conditions are not particularly limited. For example, a hot plate is used for heating and firing. In general, also considering the desired charge transportability, etc., the firing temperature is in the range of 100 to 260°C, and the firing time is appropriately determined in the range of 1 minute to 1 hour. Furthermore, if necessary, multi-stage firing may be performed at two or more different temperatures.

The thickness of the charge-transporting thin film is not particularly limited, but when used as a functional layer of an organic EL device, it is preferably 5 to 300 nm. As a method of changing the film thickness, for example, there is a method of changing the solid content concentration in the charge transporting composition, or changing the amount of liquid at the time of coating.

[Organic EL element] The organic EL device of the present invention has a pair of electrodes, and the charge-transporting thin film of the present invention is a functional layer between these electrodes.

Representative configurations of organic EL elements include the following (a) to (f), but are not limited thereto. In the following configuration, an electron blocking layer or the like may be provided between the light-emitting layer and the anode, and a hole blocking layer or the like may be provided between the light-emitting layer and the cathode as necessary. In addition, the hole injection layer, the hole transport layer, or the hole injection transport layer may also function as an electron blocking layer, etc., and the electron injection layer, electron transport layer, or electron injection transport layer may also function as hole blocking. Level function. Furthermore, if necessary, arbitrary functional layers may be provided between the layers. (a) Anode/hole injection layer/hole transport layer/light emitting layer/electron transport layer/electron injection layer/cathode (b) Anode/hole injection layer/hole transport layer/light emitting layer/electron injection transport layer/cathode (c) Anode/hole injection transport layer/light emitting layer/electron transport layer/electron injection layer/cathode (d) Anode/hole injection transport layer/light emitting layer/electron injection transport layer/cathode (e) Anode/hole injection layer/hole transport layer/light emitting layer/cathode (f) Anode/hole injection transport layer/light emitting layer/cathode

The so-called "hole injection layer", "hole transport layer" and "hole injection transport layer" are layers formed between the light-emitting layer and the anode, and have the function of transporting holes from the anode to the light-emitting layer. When only one layer of hole transporting material is provided between the light emitting layer and the anode, it is a "hole injection transporting layer", and two or more layers of hole transporting material are provided between the light emitting layer and the anode At this time, the layer close to the anode is the "hole injection layer", and the other layers are the "hole transport layer". In particular, the hole injection (transport) layer uses a film that is excellent not only in hole acceptability from the anode but also hole injection in the hole transport (light-emitting) layer.

The so-called "electron injection layer", "electron transport layer" and "electron injection transport layer" are layers formed between the light-emitting layer and the cathode, and have the function of transporting electrons from the cathode to the light-emitting layer. When only one electron-transporting material layer is provided between the light-emitting layer and the cathode, it is an "electron injection-transporting layer". When two or more electron-transporting material layers are provided between the light-emitting layer and the cathode, it is close to The layer of the cathode is the "electron injection layer", and the other layers are the "electron transport layer".

The so-called "light-emitting layer" is an organic layer with light-emitting function. When a doping system is used, it includes a host material and a doping material. At this time, the host material mainly promotes the recombination of electrons and holes, and has the function of closing the excitons into the light-emitting layer, and the doping material has the function of making the excitons obtained by the recombination emit light efficiently. In the case of a phosphorescent element, the host material has a function of mainly shutting excitons generated by dopants into the light-emitting layer.

The charge-transporting thin film of the present invention is in an organic EL device, and is suitable as a functional layer provided between an anode and a light-emitting layer, and is more suitable as a hole injection layer, a hole transport layer, and a hole injection transport layer. Suitable as a hole injection layer.

Examples of materials used and methods for producing organic EL devices using the charge-transporting composition of the present invention include the following, but are not limited thereto.

An example of a method for manufacturing an OLED device having a hole transport layer composed of a thin film obtained from the charge transporting composition of the present invention is as follows. In addition, the electrode system is preferably within a range that does not adversely affect the electrode, and it is preferable to previously perform surface treatment such as washing with alcohol, pure water, etc., UV ozone treatment, and oxygen-plasma treatment.

On the anode substrate, a hole injection layer made of the charge-transporting thin film of the present invention is formed by the aforementioned method. It is introduced into a vacuum evaporation device, and the hole transport layer, the light emitting layer, the electron transport layer, the electron transport layer/hole barrier layer, and the cathode metal are deposited in order. Alternatively, instead of forming the hole transport layer and the light emitting layer by vapor deposition in this method, a composition for forming a hole transport layer containing a hole transporting polymer and a composition for forming a light emitting layer containing a light emitting polymer are used instead These layers are formed by a wet process. Also, if necessary, an electron blocking layer may be formed between the light emitting layer and the hole transport layer.

As the anode material, a transparent electrode typified by indium tin oxide (ITO), indium zinc oxide (IZO), or a metal anode composed of a metal typified by aluminum or these alloys, etc. Jia Wei is a person who has already performed a flattening process. Polythiophene derivatives or polyaniline derivatives having high charge transportability can also be used. In addition, examples of other metals constituting the metal anode include gold, silver, copper, indium, and alloys thereof, but are not limited thereto.

Examples of the material for forming the light-emitting layer include aluminum complexes of 8-hydroxyquinoline such as (8-hydroxyquinoline) aluminum (III) (Alq ₃ ) and bis(8-hydroxyquinoline) zinc (II). Compounds, metal complexes such as zinc complexes, metal complexes of 10-hydroxybenzo[h]quinoline, bisstyrylbenzene derivatives, bisstyryl aryl derivatives, (2-hydroxyl Low molecular luminescent materials such as metal complexes of phenyl)benzothiazole, thiazole derivatives, etc.; poly(p-phenylene vinylidene), poly[2-methoxy-5-(2-ethylhexyl Oxy)-1,4-phenylene vinylene], poly(3-alkylthiophene), polyvinylcarbazole, and other polymer compounds mixed with light-emitting materials and electronic mobile materials, etc., but not subject to These are limited. In addition, when the light-emitting layer is formed by vapor deposition, it may be co-deposited with a light-emitting dopant. Examples of the light-emitting dopant include ginseng (2-phenylpyridine), iridium (III) (Ir(PPy) ₃ ), etc., or condensed polycyclic aromatic rings, such as condensed tetraphenyl derivatives such as rubrene, quinacridone derivatives, perylene, etc., but not limited thereto.

二唑衍生物、三唑衍生物、啡啉衍生物、苯基喹喔啉衍生物、苯并咪唑衍生物、嘧啶衍生物等，惟不受此等所限定。As the material for forming the electron transport layer/hole blocking layer, there may be mentioned

Diazole derivatives, triazole derivatives, morpholine derivatives, phenylquinoxaline derivatives, benzimidazole derivatives, pyrimidine derivatives, etc., but not limited thereto.

Examples of materials for forming the electron injection layer include metal oxides such as lithium oxide (Li ₂ O), magnesium oxide (MgO), and aluminum oxide (Al ₂ O ₃ ), lithium fluoride (LiF), and sodium fluoride ( NaF) metal fluoride, but not limited by these.

Examples of the cathode material include aluminum, magnesium-silver alloy, aluminum-lithium alloy, etc., but they are not limited thereto.

Examples of the material for forming the electron blocking layer include ginseng (phenylpyrazole) iridium and the like, but it is not limited thereto.

Examples of the hole transporting polymer include poly[(9,9-dihexyloxy-2,7-diyl)-co-(N,N'-bis{p-butylphenyl}-1, 4-diaminophenylphenyl)], poly[(9,9-dioctyl-chrysyl-2,7-diyl)-co-(N,N'-bis{p-butylphenyl}-1, 1'-biphenyl-4,4-diamine)], poly[(9,9-bis{1'-pentene-5'-yl} stilbene-2,7-diyl)-co- (N,N'-bis{p-butylphenyl}-1,4-diaminophenylphenyl)], poly[N,N'-bis(4-butylphenyl)-N,N'-bis (Phenyl)-benzidine)-terminated polysilsesquioxane, poly((9,9-bisdioctyl stilbene-2,7-diyl)-co-(4,4'-( N-(p-butylphenyl))diphenylamine)] etc.

Examples of the light-emitting polymer include polyfluorene derivatives such as poly(9,9-dialkyl stilbene) (PDAF), poly(2-methoxy-5-(2'-ethylhexyloxy) -1,4-phenylene vinylidene) (MEH-PPV) and other polyphenylene vinylidene derivatives, poly(3-alkylthiophene) (PAT) and other polythiophene derivatives, polyvinylcarbazole (PVCz) etc.

The materials constituting the layer formed between the anode and the cathode and these are different according to the manufacture of an element having any one of a bottom-emission structure and a top-emission structure, so it is appropriate to select the material in consideration of this point.

Generally, in the element of the bottom-emission structure, a transparent anode is used on the substrate side to extract light from the substrate side. In contrast, in the element of the top-emission structure, a reflective anode made of metal is used from the opposite direction to the substrate Light is extracted from the transparent electrode (cathode) side. Therefore, for example, for the anode material, a transparent anode such as ITO is used when manufacturing an element with a bottom emission structure, and a reflective anode such as Al/Nd is used when manufacturing an element with a top emission structure.

In order to prevent the deterioration of the characteristics, the organic EL device of the present invention may be sealed with a water-collecting agent or the like as necessary according to a general method. [Example]

Hereinafter, the present invention will be described more specifically with examples, but the present invention is not limited to the following examples. In addition, the device used is as follows. (1) LDI-MS: AutoFlex manufactured by Bruker Corporation (2) ¹ H-NMR: JNM-ECP300 FT NMR SYSTEM manufactured by JEOL Ltd. (3) Substrate cleaning: substrate cleaning device manufactured by Changzhou Industry Co., Ltd. Piezoelectric paste method) (4) Coating of the composition: Spin coater MS-A100 made by MIKASA (shares) (5) Film thickness measurement: (shares) Surfcorder ET-4000 fine shape measuring machine made by Kosaka Research Institute (6) Production of components: Multi-functional vapor deposition system C-E2L1G1-N manufactured by Changzhou Industrial Co., Ltd. (7) Measurement of current density of components: Multi-channel IVL measuring equipment manufactured by EHC (8) Refractive index (n) And extinction coefficient (k) measurement: JAWoollan Japan Corporation multi-incidence angle spectroscopic ellipsometer VASE

[1] Production of compound [Synthesis Example 1]

In a flask, put 0.502g of 1,4-phenylenediamine, 6.26g of 2-bromo-9-phenyl-9H-carbazole, 0.106g of bis(dibenzylideneacetone)palladium and 2.24 of sodium tributoxide g. Nitrogen was replaced in the flask. To this, 10 mL of toluene and 1.3 mL of a toluene solution of phenylditributylphosphine prepared in advance (concentration: 62.5 g/L) were added, and stirred at 90° C. for 3 hours. After the reaction mixture was cooled to room temperature, together with the cooled reaction mixture, toluene and saturated saline were placed in a separatory funnel, subjected to liquid separation treatment, and the organic layer was recovered. Activated carbon was added to the recovered organic layer, and after stirring at room temperature for 0.5 hours, silica gel filtration was performed, and the resulting filtrate was concentrated. The resulting concentrated drops were dropped into a mixed solvent of methanol and ethyl acetate, and stirred for a while. The resulting slurry solution was filtered, and the resulting filtrate was dried to obtain 2.96 g of the intended p-aniline derivative A (yield: 59%). The obtained target substance was identified by ¹ H-NMR.

[2] Preparation of charge transport composition and evaluation of storage stability [Example 1-1] In a mixture of 0.243 g of aniline derivative A and 0.283 g of arylsulfonate B represented by the following formula, 10 g of xylene was added, stirred and dissolved at room temperature, and the resulting solution was filtered through a syringe filter with a pore diameter of 0.2 μm to obtain a charge-transporting composition. In addition, arylsulfonate B was synthesized according to the method described in International Publication No. 2017/217457 (the same applies hereinafter).

[Example 1-2] To a mixture of 0.243 g of aniline derivative A and 0.283 g of arylsulfonate B, add 5 g of triethylene glycol butyl methyl ether, 3 g of butyl benzoate and 2 g of dimethyl phthalate, and stir at room temperature Then, it was dissolved, and the resulting solution was filtered with a syringe filter with a pore size of 0.2 μm to obtain a charge-transporting composition.

[Example 1-3] To a mixture of 0.243g of aniline derivative A and 0.283g of aryl sulfonate B, add 3g of 3-phenoxytoluene and 7g of butyl benzoate, and stir at room temperature to dissolve, with a pore size of 0.2μm The syringe filter filters the resulting solution to obtain a charge-transporting composition.

[Comparative Example 1-1] Except for using the aniline derivative C represented by the following formula instead of the aniline derivative A, an attempt was made to prepare a charge transporting composition in the same manner as in Example 1-1. However, the solid component does not dissolve even when stirred at room temperature, and the solid component does not dissolve even when heated and stirred at 50°C. When heated and stirred at 80°C, the solid component dissolves. The obtained solution was filtered with a syringe filter with a pore size of 0.2 μm to obtain a charge transporting composition. In addition, the aniline derivative C was synthesized according to the method described in International Publication No. 2015/137395.

[Comparative Example 1-2] Except for using the aniline derivative C instead of the aniline derivative A, in the same manner as in Example 1-2, an attempt was made to prepare a charge transporting composition. However, the solid component does not dissolve even when stirred at room temperature, and the solid component does not dissolve even when heated and stirred at any temperature of 50°C or 80°C, and a uniform charge that can produce a charge-transporting thin film cannot be obtained Transportable composition.

[Comparative Example 1-3] Except for using the aniline derivative C instead of the aniline derivative A, in the same manner as in Examples 1-3, an attempt was made to prepare a charge transporting composition. However, the solid component does not dissolve even when stirred at room temperature, and the solid component does not dissolve even when heated and stirred at 50°C. When heated and stirred at 80°C, the solid component dissolves. The obtained solution was filtered with a syringe filter with a pore size of 0.2 μm to obtain a charge transporting composition.

The obtained composition was stored at 0°C for 1 week, and it was confirmed whether the solid content of the composition after storage was precipitated. Table 1 shows the results and the solubility of the solid components during the preparation of each composition.

[Table 1]

As is clear from Table 1, even if the composition of the present invention is composed of any solvent, no precipitation is observed. On the other hand, in the composition containing the comparative example of the aniline derivative C having a structure similar to the aniline derivative A used in the present invention, precipitation was observed. From the results, it can be seen that the composition of the present invention is superior in storage stability compared to the composition of the comparative example.

[3] Evaluation of the optical properties of the film [Example 2 and Comparative Example 2] The charge-transporting compositions obtained in Example 1-1 and Comparative Example 1-1 were each applied to a quartz substrate using a spin coater, and then dried at 80°C for 1 minute in an atmospheric environment, followed by firing at 200°C. In 15 minutes, a 60 nm uniform thin film was formed on the substrate. The extinction coefficient k (average extinction coefficient at a wavelength of 400 nm to 800 nm) and the refractive index n (average refractive index at a wavelength of 400 nm to 800 nm) of each film were measured. Table 2 shows the results.

[Table 2]

As is clear from Table 2, the film obtained from the composition of the present invention exhibits a lower extinction coefficient, high transparency and high refractive index compared to the film obtained from the composition of the comparative example.

[4] Fabrication and evaluation of a hole-only device In the following example, as an ITO substrate, an indium tin oxide (ITO) patterned with a thickness of 150 nm on the surface of 25 mm × 25 mm × 0.7 was used. The glass substrate of t is cleaned of impurities on the surface by an O ₂ plasma cleaning device (150 W, 30 seconds) before use.

[Example 3] After applying the composition obtained in Example 1-1 to an ITO substrate using a spin coater, it was dried at 80°C for 1 minute in the atmosphere, followed by firing at 200°C for 15 minutes to produce a 60nm film Thick charge transport film. On it, an evaporation device (vacuum degree 1.0×10 ^-5 Pa, evaporation rate 0.2 nm/sec) was used as the hole transport layer, and α-NPD(N,N′-di( 1-naphthyl)-N,N'-diphenylbenzidine) film was formed at 30 nm, and an 80 nm aluminum thin film was formed thereon to fabricate components.

[Comparative Example 3] An element was produced in the same manner as in Example 3 except that instead of the composition obtained in Example 1-1, the composition obtained in Comparative Example 1-1 was used.

[Example 4] In the same manner as in Example 3, a charge transport thin film was formed on the ITO substrate. On it, after applying 0.6 mass% xylene solution of TFB polymer (LT-N148 manufactured by Luminescence Technology Co., Ltd.) by spin coating in a glove box under a nitrogen atmosphere, it was fired at 130°C for 10 minutes to form 20 nm The charge-transporting film acts as a hole-transporting layer. Furthermore, an 80 nm aluminum thin film was formed in the same manner as in Example 3 to fabricate an element.

[Comparative Example 4] An element was produced in the same manner as in Example 4 except that instead of the composition obtained in Example 1-1, the composition obtained in Comparative Example 1-1 was used.

The current density when driving the fabricated element at a driving voltage of 5V was measured. Table 3 shows the results.

[table 3]

As shown in Table 3, the charge-transporting thin film obtained from the composition of the present invention is superior to the hole-transporting layer into the hole-transporting layer, compared with the charge-transporting thin film obtained from the composition of the comparative example. By using the charge-transporting thin film obtained from the composition of the present invention, an organic EL device with high characteristics can be expected.

Claims (8)

A charge transporting composition comprising an aniline derivative represented by the following formula (1);

[In the formula, each Ar is independently a group represented by any one of the following formulas (Ar1) to (Ar9);

(Wherein, R ¹ ~ R ²¹ are each independently a hydrogen atom based, Z can be ^a substituted alkyl group of 1 to 20 carbon atoms, which may be substituted with Z ¹ of alkenyl having 2 to 20, Z ¹ may be Substituted C 2-20 alkynyl group, Z ² substituted C 6-20 aryl group or Z ² substituted C 2-20 heteroaryl group, Z ¹ is a halogen atom, nitro group , cyano, Z ³ may be substituted or an aryl group of carbon number of Z ³ may be substituted with a carbon number of 6 to 20 heteroaryl group having 2 to 20, Z ² based halogen atom, a nitro group, a cyano group, Z may be ³ substituted C 1-20 alkyl group, Z ² substituted C 2-20 alkenyl group or Z ³ substituted C 2-20 alkynyl group, Z ³ is a halogen atom, nitro group Or cyano)]. As in the charge transport composition of claim 1, Ar is the same basis. The charge-transporting composition according to claim 2, wherein Ar is a group represented by any one of formulas (Ar1) to (Ar5). The charge transporting composition according to claim 3, wherein Ar is a group represented by formula (Ar1). The charge transporting composition according to any one of claims 1 to 4, which further contains a dopant. The charge transporting composition according to claim 5, wherein the aforementioned dopant is an arylsulfonate compound. A charge-transporting film produced using the charge-transporting composition according to any one of claims 1 to 5. An organic electroluminescence device provided with the charge transporting film according to claim 7.