JP6775731B2 - Charge transport material and its use - Google Patents

Description

An embodiment of the present invention relates to a charge transporting material and an ink composition using the material. In addition, another embodiment of the present invention includes an organic layer using the charge transporting material or the ink composition, and an organic electronics element, an organic electroluminescence element, a display element, and a lighting device having the organic layer. , And the display device.

Organic electronics devices are devices that perform electrical operations using organic substances, and are expected to exhibit features such as energy saving, low cost, and flexibility, and are attracting attention as a technology that replaces conventional silicon-based inorganic semiconductors. ing.

Examples of organic electronics devices include organic electroluminescence devices (hereinafter, also referred to as “organic EL devices”), organic photoelectric conversion devices, and organic transistors.

Among organic electronic devices, organic EL devices are attracting attention as large-area solid-state light source applications as alternatives to incandescent lamps and gas-filled lamps, for example. It is also attracting attention as the most promising self-luminous display that can replace the liquid crystal display (LCD) in the flat panel display (FPD) field, and its commercialization is progressing.

Organic EL devices are roughly classified into two types, low molecular weight organic EL devices and high molecular weight organic EL devices, according to the organic materials used. In the high molecular weight organic EL device, a high molecular weight material is used as the organic material, and in the low molecular weight organic EL device, a low molecular weight material is used. Compared to low-molecular-weight organic EL devices, which are mainly formed in a vacuum system, high-molecular-weight organic EL devices can be easily formed by wet processes such as printing and inkjet. It is expected as an indispensable element for EL displays.

Therefore, the development of a material suitable for a wet process is underway (Patent Document 1).

Japanese Unexamined Patent Publication No. 2006-279007

In general, an organic EL device manufactured by a wet process using a polymer material has features that it is easy to reduce the cost and increase the area. However, an organic EL device containing a thin film produced by using a conventional polymer material is desired to be further improved in the characteristics of the organic EL device such as driving voltage, luminous efficiency, and luminous life. Further, since high-temperature baking is required for producing an organic EL device, high-temperature process resistance is also desired for each material.

In view of the above, the embodiment of the present invention provides a charge transporting material containing a polymer compound that can be used for an organic electronic device and having high temperature process resistance suitable for a wet process, and an ink composition containing the material. The purpose is. In another embodiment, the charge transporting material or the ink composition is used to provide an organic electronic device and an organic EL device having excellent life characteristics, and a display device, a lighting device, and a display using the same. The purpose is to provide the device.

One embodiment of the present invention relates to a charge transporting material containing a charge transporting polymer having a thermogravimetric loss of 5% by mass or less when heated at 300 ° C.

Another embodiment of the present invention relates to an ink composition containing the charge transporting material of the above embodiment and a solvent.
Other embodiments of the present invention relate to an organic layer formed using the charge transport material of the above embodiment or the ink composition of the above embodiment.
Another embodiment of the present invention relates to an organic electronic device having the organic layer of the above embodiment.
Another embodiment of the present invention relates to an organic electroluminescent device having the organic layer of the above embodiment.

Another embodiment of the present invention relates to a display device including the organic electroluminescence device of the above embodiment.
Another embodiment of the present invention relates to a lighting device including the organic electroluminescence element of the above embodiment.
Further, another embodiment of the present invention relates to a display device including the lighting device of the above embodiment and a liquid crystal element as a display means.

According to an embodiment of the present invention, an organic electronics element, an organic EL element, which are excellent in durability at a high temperature and excellent in life characteristics, and a display element, a lighting device, and a display device using the same are provided. Can be done.

It is a schematic cross-sectional view which shows an example of the organic EL element which is one Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described, but the present invention is not limited to these embodiments.
<Charge transport material>
The charge transporting material of the present embodiment (also referred to as “organic electronics material” in the present specification) has a charge such that the thermal weight loss when heated at 300 ° C. is 5% by mass or less with respect to the mass before heating. It is characterized by containing a transportable polymer. The charge-transporting material may contain a plurality of types of charge-transporting polymers, in which case the charge-transporting polymer as a mixture may satisfy the above thermogravimetric characteristics as a whole.
The charge-transporting polymer is a polymer having an ability to transport charges, and the "polymer" is a concept including a so-called "oligomer" having a small number of repetitions of structural units.

When the thermogravimetric reduction of the charge transport polymer is 5% by mass or less with respect to the mass before heating, the charge transport material can be imparted with high temperature process resistance and the heat resistance can be improved. If the heat resistance of the charge transport material is high, the performance of the organic layer using the material will not be deteriorated due to, for example, a high temperature bake (for example, more than 200 ° C. to less than 300 ° C.) when manufacturing an organic EL device. High carrier mobility can be maintained. As a result, it is considered that the drive voltage can be lowered, the luminous efficiency can be improved, and the life can be extended.
This thermal weight reduction is more preferably 4.5% by mass or less, further preferably 4.3% by mass or less, and even more preferably 4.1% by mass or less.

The thermogravimetric reduction ratio of the charge-transporting polymer when heated to 300 ° C. refers to the thermogravimetric reduction (mass%) when the polymer to be measured is heated to 300 ° C. in air under a heating condition of 5 ° C./min. .. Specifically, 10 mg of the measurement polymer can be used for measurement using a thermogravimetric-differential thermal (TG-DTA) analyzer.

[Charge transport polymer]
As described above, the charge-transporting polymer of the present embodiment is characterized by having a small thermogravimetric loss.
In order to control the thermogravimetric reduction of the polymer, for example, the thermogravimetric reduction of the polymer can be reduced by increasing the ring structure such as the aromatic ring (aryl group or heteroaryl group) contained in the polymer molecule. it can. Specifically, it is preferable to introduce a condensed or non-condensed polycyclic structure as the structural unit T, L or B described later.
On the other hand, if the molecule has a structure that is easily cleaved by heating, such as an ether bond or an ester bond, the thermogravimetric decrease tends to be large, so it is preferable to adjust the content of these structures.

The charge-transporting polymer may be linear or may have a branched structure. The charge-transporting polymer preferably contains at least a divalent structural unit L having charge transportability and a monovalent structural unit T constituting the terminal portion, and contains a trivalent or higher-valent structural unit B constituting the branch portion. Further may be included. The charge-transporting polymer may contain only one type of each structural unit, or may contain a plurality of types of each structural unit. In charge-transporting polymers, the structural units are attached to each other at "monovalent" to "trivalent or higher" binding sites.

(Construction)
Examples of the partial structure contained in the charge transport polymer include the following. The charge-transporting polymer is not limited to the polymer having the following partial structure. In the partial structure, "L" represents the structural unit L, "T" represents the structural unit T, and "B" represents the structural unit B. "*" Represents a binding site with another structural unit. In the following substructures, the plurality of Ls may be the same structural unit or different structural units from each other. The same applies to T and B.

Linear charge transport polymer

Charge-transporting polymer with branched structure

In one embodiment, the charge-transporting polymer preferably has a charge-transporting divalent structural unit. Further, in one embodiment, the charge-transporting polymer preferably has a structure branched in three or more directions, that is, has the structural unit B.

The charge transport polymer preferably contains one or more structures selected from the group consisting of an aromatic amine structure, a carbazole structure, a thiophene structure, a bithiophene structure, a benzene structure, and a fluorene structure, and this structure is preferable. Although it is included in the structural unit L described below, it may be included in the structural unit B, or may be included in both the structural unit L and the structural unit B. By including any of these structures, charge transportability, particularly hole transportability, can be improved.

Alternatively, from the viewpoint of improving charge transportability, particularly hole transportability, the charge transport polymer in one embodiment preferably contains an N-arylphenoxazine structure. This N-arylphenoxazine structure is preferably contained in the structural unit B, but may be contained in the structural unit L, or may be contained in both the structural unit B and the structural unit L. The aryl group having an N-arylphenoxazine structure is preferably a phenyl group, a naphthyl group or the like. These aryl groups may be substituted with linear, cyclic or branched alkyl groups having 1 to 22 carbon atoms.

(Structural unit L)
The structural unit L is a divalent structural unit having charge transportability. The structural unit L is not particularly limited as long as it includes an atomic group capable of transporting electric charges. For example, the structural unit L is a substituted or unsubstituted aromatic amine structure, carbazole structure, thiophene structure, bithiophene structure, fluorene structure, benzene structure, biphenylene structure, terphenylene structure, naphthalene structure, anthracene structure, tetracene structure, phenanthrene. Structure, dihydrophenanthrene structure, pyridine structure, pyrazine structure, quinoline structure, isoquinoline structure, quinoxaline structure, aclysin structure, diazaphenanthrene structure, furan structure, pyrrole structure, oxazole structure, oxadiazole structure, thiazole structure, thiadiazole structure, triazole Select from structure, benzothiophene structure, benzoxazole structure, benzoxaziazole structure, benzothiazole structure, benzothiadiazole structure, benzotriazole structure, N-arylphenoxazine structure, and a structure containing one or more of these. Will be done. The aromatic amine structure is preferably a triarylamine structure, more preferably a triphenylamine structure.

In one embodiment, the structural unit L is a substituted or unsubstituted aromatic amine structure, carbazole structure, thiophene structure, bithiophene structure, fluorene structure, benzene structure, pyrrole structure, from the viewpoint of obtaining excellent hole transportability. And, preferably selected from a structure containing one or more of these, a substituted or unsubstituted aromatic amine structure, a carbazole structure, and a structure containing one or more of these. It is more preferable to be done. In other embodiments, the structural unit L is a substituted or unsubstituted fluorene structure, benzene structure, phenanthrene structure, pyridine structure, quinoline structure, and one or two of these, from the viewpoint of obtaining excellent electron transportability. It is preferably selected from structures containing more than a species.

Specific examples of the structural unit L include the following. The structural unit L is not limited to the following.

R each independently represents a hydrogen atom or a substituent. Preferably, R independently comprises -R ¹ , -OR ² , -SR ³ , -OCOR ⁴ , -COOR ⁵ , -SiR ⁶ R ⁷ R ⁸ , a halogen atom, and a polymerizable functional group described below. Selected from the group of groups containing. R ^{1 to} R ⁸ each independently represent a hydrogen atom; a linear, cyclic or branched alkyl group having 1 to 22 carbon atoms; or an aryl group or a heteroaryl group having 2 to 30 carbon atoms. Aryl groups are atomic groups obtained by removing one hydrogen atom from aromatic hydrocarbons. A heteroaryl group is an atomic group obtained by removing one hydrogen atom from an aromatic heterocycle. The alkyl group may be further substituted with an aryl group or a heteroaryl group having 2 to 20 carbon atoms, and the aryl group or a heteroaryl group may be further substituted with a linear, cyclic or branched having 1 to 22 carbon atoms. It may be substituted with an alkyl group. R is preferably a hydrogen atom, an alkyl group, an aryl group, or an alkyl-substituted aryl group. Ar represents an arylene group or a heteroarylene group having 2 to 30 carbon atoms. An arylene group is an atomic group obtained by removing two hydrogen atoms from an aromatic hydrocarbon. A heteroarylene group is an atomic group obtained by removing two hydrogen atoms from an aromatic heterocycle. Ar is preferably an arylene group, more preferably a phenylene group.

Examples of the aromatic hydrocarbon include a monocyclic ring, a condensed ring, and a polycycle in which two or more selected from a monocyclic ring and a condensed ring are bonded via a single bond. Examples of the aromatic heterocycle include a monocyclic ring, a condensed ring, and a polycyclic ring in which two or more selected from a monocyclic ring and a condensed ring are bonded via a single bond.

(Structural unit T)
The structural unit T is a monovalent structural unit constituting the terminal portion of the charge-transporting polymer. The structural unit T is not particularly limited, and is selected from, for example, a substituted or unsubstituted aromatic hydrocarbon structure, an aromatic heterocyclic structure, and a structure containing one or more of these. The structural unit T may have the same structure as the structural unit L. In one embodiment, the structural unit T is preferably a substituted or unsubstituted aromatic hydrocarbon structure from the viewpoint of imparting durability without reducing charge transportability, and is preferably a substituted or unsubstituted benzene. The structure is more preferable. Further, in another embodiment, as described later, when the charge-transporting polymer has a polymerizable functional group at the terminal portion, the structural unit T has a polymerizable structure (for example, a polymerizable functional group such as a pyrrole-yl group). ) May be.

Specific examples of the structural unit T include the following. The structural unit T is not limited to the following.

R is the same as R in the structural unit L. When the charge-transporting polymer has a polymerizable functional group at the terminal portion, preferably at least one of R is a group containing a polymerizable functional group.

In one embodiment, it is preferable to introduce a polycyclic aromatic hydrocarbon, a polycyclic structure based on an aromatic amine or the like as the structural unit T in order to reduce the thermal weight loss of the charge transport polymer. For example, examples of the polycyclic aromatic hydrocarbon structure include atomic groups obtained by removing one hydrogen atom from naphthalene, anthracene, phenanthrene, pyrene, benzopyrene and the like. As the aromatic amine structure, a triarylamine structure is preferable, and more specifically, triphenylamine, phenylnaphthylamine (N-phenyl-1-naphthylamine, etc.), diphenylnaphthylamine (N, N-diphenyl-1-naphthylamine, etc.). , Phenyldinaphthylamine (N-phenyl-2,2'-naphthylamine, etc.), trinaphthylamine, etc., from which one hydrogen atom has been removed. Two or more of these structures may be combined.

When these polycyclic structures are introduced as the structural unit T, the polycyclic structure is preferably 50 mol% or more, preferably 60 mol% or more, and 70 mol% or more, based on the total structural unit T. , This order is more preferable. Alternatively, based on all the structural units L, T, and B, these polycyclic structures are preferably 15 to 50 mol%.

(Structural unit B)
The structural unit B is a trivalent or higher structural unit constituting the branched portion when the charge-transporting polymer has a branched structure. The structural unit B is preferably hexavalent or less, and more preferably trivalent or tetravalent, from the viewpoint of improving the durability of the organic electronic device. The structural unit B is preferably a unit having charge transportability. For example, the structural unit B is a substituted or unsubstituted aromatic amine structure, carbazole structure, condensed polycyclic aromatic hydrocarbon structure, and one or two of them from the viewpoint of improving the durability of the organic electronic device. Selected from structures containing more than a species.

Specific examples of the structural unit B include the following. The structural unit B is not limited to the following.

W represents a trivalent linking group, for example, an arenetriyl group having 2 to 30 carbon atoms or a heteroarene triyl group. The arenetriyl group is an atomic group obtained by removing three hydrogen atoms from an aromatic hydrocarbon. A heteroarene triyl group is an atomic group obtained by removing three hydrogen atoms from an aromatic heterocycle. Ar independently represents a divalent linking group, for example, each independently represents an arylene group or a heteroarylene group having 2 to 30 carbon atoms. Ar is preferably an arylene group, more preferably a phenylene group. Y represents a divalent linking group, and for example, from the group having one or more hydrogen atoms in R (excluding the group containing a polymerizable functional group) in the structural unit L, one more hydrogen atom. Divalent groups excluding. Z represents either a carbon atom, a silicon atom, or a phosphorus atom. In the structural unit, the benzene ring and Ar may have a substituent, and examples of the substituent include R in the structural unit L.

In one embodiment, the structural unit B preferably contains a heteroarylene structure in order to reduce the thermogravimetric loss of the charge-transporting polymer, among which the aromatic amine structure, the carbazole structure, and the N-arylphenoxazine. The structure and the like are preferable. The heteroarylene structure as the structural unit B is preferably 50 mol% or more, and 60 mol% or more, 70 mol% or more, and 80 mol% or more based on the total structural unit B. More preferred in order.

(Polymerizable functional group)
In one embodiment, the charge-transporting polymer preferably has at least one polymerizable functional group from the viewpoint of curing by a polymerization reaction and changing the solubility in a solvent. The "polymerizable functional group" refers to a functional group capable of forming a bond with each other by applying heat and / or light.
For example, when the hole injection layer contains a polymerization initiator and the hole transport layer uses a charge transport polymer having a polymerizable substituent, the hole transport layer can be cured, and thus the upper layer thereof. It is possible to apply a light emitting layer made of an electric charge or the like without dissolving the hole transport layer. In general, since the light emitting layer is coated with an aromatic hydrocarbon solvent, it is preferable to use a charge-transporting polymer that is difficult to dissolve even when immersed in toluene by introducing a polymerizable functional group.

The polymerizable functional group includes a group having a carbon-carbon multiple bond (for example, vinyl group, allyl group, butenyl group, ethynyl group, acryloyl group, acryloyloxy group, acryloylamino group, methacryloyl group, methacryloyloxy group, methacryloylamino). Group, vinyloxy group, vinylamino group, etc.), group having a small ring (for example, cyclic alkyl group such as cyclopropyl group, cyclobutyl group; cyclic ether group such as epoxy group (oxylanyl group), oxetan group (oxetanyl group)) Examples include a diketen group; an episulfide group; a lactone group; a lactam group, etc.), a heterocyclic group (for example, a furan-yl group, a pyrrol-yl group, a thiophen-yl group, a silol-yl group) and the like. As the polymerizable functional group, a vinyl group, an acryloyl group, a methacryloyl group, an epoxy group, and an oxetane group are particularly preferable, and a vinyl group, an oxetan group, or an epoxy group is more preferable from the viewpoint of reactivity and characteristics of the organic electronic device. preferable.

From the viewpoint of increasing the degree of freedom of the polymerizable functional group and facilitating the occurrence of a polymerization reaction, it is preferable that the main skeleton of the charge-transporting polymer and the polymerizable functional group are linked by an alkylene chain. Further, for example, when an organic layer is formed on an electrode, it may be connected by a hydrophilic chain such as an ethylene glycol chain or a diethylene glycol chain from the viewpoint of improving the affinity with a hydrophilic electrode such as ITO. preferable. In addition, from the perspective of facilitating the preparation of monomers used to introduce polymerizable functional groups, the charge-transporting polymer polymerizes with the ends of alkylene and / or hydrophilic chains, i.e., those chains. An ether bond or an ester bond may be provided at the connecting portion with the sex functional group and / or at the connecting portion between these chains and the skeleton of the charge-transporting polymer. The above-mentioned "group containing a polymerizable functional group" means a polymerizable functional group itself or a group in which a polymerizable functional group and an alkylene chain are combined. As the group containing a polymerizable functional group, for example, the group exemplified in International Publication No. WO2010 / 1405553 can be preferably used.

The polymerizable functional group is introduced at the terminal portion (that is, the structural unit T) of the charge-transporting polymer or at a portion other than the terminal portion (that is, the structural unit L or B). It may be introduced in both the and non-terminal parts. From the viewpoint of curability, it is preferable that it is introduced at least at the terminal portion, and from the viewpoint of achieving both curability and charge transportability, it is preferable that it is introduced only at the terminal portion. Further, when the charge-transporting polymer has a branched structure, the polymerizable functional group may be introduced into the main chain or the side chain of the charge-transporting polymer, and both the main chain and the side chain may be introduced. It may be introduced in.

From the viewpoint of contributing to the change in solubility, the polymerizable functional group is preferably contained in a large amount in the charge-transporting polymer. On the other hand, from the viewpoint of not hindering the charge transportability, it is preferable that the amount contained in the charge transport polymer is small. The content of the polymerizable functional group can be appropriately set in consideration of these.

For example, the number of polymerizable functional groups per molecule of the charge-transporting polymer is preferably 2 or more, and more preferably 3 or more, from the viewpoint of obtaining a sufficient change in solubility. The number of polymerizable functional groups is preferably 1,000 or less, more preferably 500 or less, from the viewpoint of maintaining charge transportability.

The number of polymerizable functional groups per molecule of the charge-transporting polymer is the amount of the polymerizable functional group charged (for example, the amount of the monomer having the polymerizable functional group) used for synthesizing the charge-transporting polymer, and each structure. It can be obtained as an average value by using the amount of the monomer charged corresponding to the unit, the mass average molecular weight of the charge transport polymer, and the like. The number of polymerizable functional groups is the ratio of the integrated value of the signal derived from the polymerizable functional group in the ¹ H NMR (nuclear magnetic resonance) spectrum of the charge transport polymer to the integrated value of the entire spectrum, and the charge transport polymer. It can be calculated as an average value by using the mass average molecular weight of. Since it is simple, when the amount to be charged is clear, the value obtained by using the amount to be charged is preferably adopted.

(Number average molecular weight)
The number average molecular weight of the charge-transporting polymer can be appropriately adjusted in consideration of solubility in a solvent, film-forming property, and the like. From the viewpoint of excellent charge transportability, the number average molecular weight is preferably 500 or more, more preferably 1,000 or more, further preferably 2,000 or more, and even more preferably 5,000 or more. The number average molecular weight is preferably 1,000,000 or less, more preferably 100,000 or less, and more preferably 50,000 or less, from the viewpoint of maintaining good solubility in a solvent and facilitating the preparation of the ink composition. The following is even more preferable, and 30,000 or less is even more preferable.

(Mass average molecular weight)
The mass average molecular weight of the charge-transporting polymer can be appropriately adjusted in consideration of solubility in a solvent, film-forming property, and the like. From the viewpoint of excellent charge transportability, the mass average molecular weight is preferably 1,000 or more, more preferably 5,000 or more, further preferably 10,000 or more, and even more preferably 30,000 or more. The mass average molecular weight is preferably 1,000,000 or less, more preferably 700,000 or less, and more preferably 400,000 or less, from the viewpoint of maintaining good solubility in the solvent and facilitating the preparation of the ink composition. The following is even more preferable, and 200,000 or less and 100,000 or less are even more preferable in this order.

The number average molecular weight and the mass average molecular weight can be measured by gel permeation chromatography (GPC) using a standard polystyrene calibration line.

(Ratio of structural units)
The ratio of the structural unit L contained in the charge-transporting polymer is preferably 10 mol% or more, more preferably 20 mol% or more, and 30 mol% or more, based on all the structural units, from the viewpoint of obtaining sufficient charge transportability. Is more preferable. Further, the ratio of the structural unit L is preferably 95 mol% or less, more preferably 90 mol% or less, still more preferably 85 mol% or less, considering the structural unit T and the structural unit B to be introduced as needed.

The ratio of the structural unit T contained in the charge-transporting polymer is based on all the structural units from the viewpoint of improving the characteristics of the organic electronic device or from the viewpoint of suppressing the increase in viscosity and satisfactorily synthesizing the charge-transporting polymer. 5 mol% or more is preferable, 10 mol% or more is more preferable, and 15 mol% or more is further preferable. The ratio of the structural unit T is preferably 60 mol% or less, more preferably 55 mol% or less, still more preferably 50 mol% or less, from the viewpoint of obtaining sufficient charge transportability.

When the charge transport polymer contains the structural unit B, the ratio of the structural unit B is preferably 1 mol% or more, more preferably 5 mol% or more, based on all the structural units, from the viewpoint of improving the durability of the organic electronic device. Preferably, 10 mol% or more is more preferable. The ratio of the structural unit B is preferably 50 mol% or less, preferably 40 mol% or less, from the viewpoint of suppressing an increase in viscosity and satisfactorily synthesizing a charge-transporting polymer, or obtaining sufficient charge-transporting property. Is more preferable, and 30 mol% or less is further preferable.

When the charge-transporting polymer has a polymerizable functional group, the ratio of the polymerizable functional group is preferably 0.1 mol% or more based on all structural units from the viewpoint of efficiently curing the charge-transporting polymer. 1 mol% or more is more preferable, and 3 mol% or more is further preferable. The proportion of the polymerizable functional group is preferably 70 mol% or less, more preferably 60 mol% or less, still more preferably 50 mol% or less, from the viewpoint of obtaining good charge transportability. The "ratio of polymerizable functional groups" here means the ratio of structural units having polymerizable functional groups.

Considering the balance of charge transportability, durability, productivity, etc., the ratio (molar ratio) of the structural unit L and the structural unit T is preferably L: T = 100: 1 to 70, more preferably 100: 3 to 50. It is preferable, and 100: 5 to 30 is more preferable. When the charge transporting polymer contains the structural unit B, the ratio (molar ratio) of the structural unit L, the structural unit T, and the structural unit B is L: T: B = 100: 10 to 200: 10 to 100. Preferably, 100: 20 to 180: 20 to 90 is more preferable, and 100: 40 to 160: 30 to 80 is even more preferable.

The ratio of the structural units can be determined by using the amount of the monomer charged corresponding to each structural unit used for synthesizing the charge-transporting polymer. Further, the ratio of the structural units can be calculated as an average value by using the integrated value of the spectrum derived from each structural unit in the ¹ H NMR spectrum of the charge transport polymer. Since it is simple, when the amount to be charged is clear, the value obtained by using the amount to be charged is preferably adopted.

(Production method)
The charge-transporting polymer can be produced by various synthetic methods and is not particularly limited. For example, known coupling reactions such as Suzuki coupling, Negishi coupling, Sonoto coupling, Still coupling, Buchwald-Hartwig coupling and the like can be used. Suzuki coupling causes a cross-coupling reaction using a Pd catalyst between an aromatic boronic acid derivative and an aromatic halide. According to Suzuki Coupling, a charge-transporting polymer can be easily produced by binding desired aromatic rings to each other.

In the coupling reaction, for example, a Pd (0) compound, a Pd (II) compound, a Ni compound and the like are used as the catalyst. Further, a catalyst species generated by mixing tris (dibenzylideneacetone) dipalladium (0), palladium (II) acetate or the like as a precursor and mixing with a phosphine ligand can also be used. For the method of synthesizing the charge transport polymer, for example, the description of International Publication No. WO2010 / 1405553 can be referred to.

[Dopant]
The charge transport material may further contain a dopant. The dopant is not particularly limited as long as it is a compound capable of exhibiting a doping effect and improving charge transportability by adding it to a charge transporting material. Doping includes p-type doping and n-type doping. In p-type doping, a substance that acts as an electron acceptor as a dopant is used, and in n-type doping, a substance that acts as an electron donor as a dopant is used. It is preferable to perform p-type doping for improving hole transportability and n-type doping for improving electron transportability. The dopant used in the charge transporting material may be a dopant that exhibits either the p-type doping or the n-type doping effect. Further, one kind of dopant may be added alone, or a plurality of kinds of dopants may be mixed and added.

The dopant used for p-type doping is an electron-accepting compound, and examples thereof include Lewis acid, protonic acid, transition metal compound, ionic compound, halogen compound, and π-conjugated compound. Specifically, as Lewis acid, FeCl ₃ , PF ₅ , AsF ₅ , SbF ₅ , BF ₅ , BCl ₃ , BBr _3, etc .; as sulfonic acid, HF, HCl, HBr, HNO ₅ , H ₂ SO ₄ , inorganic acids such as HClO _4, benzenesulfonic acid, p- toluenesulfonic acid, dodecylbenzenesulfonic acid, polyvinyl sulfonic acid, methanesulfonic acid, trifluoromethanesulfonic acid, trifluoroacetic acid, 1-butane sulfonic acid, vinyl phenyl sulfonate , Organic acids such as camphorsulfonic acid; as transition metal compounds, FeOCl, TiCl ₄ , ZrCl ₄ , HfCl ₄ , NbF ₅ , AlCl ₃ , NbCl ₅ , TaCl ₅ , MoF ₅ ; as ionic compounds, tetrakis (pentafluoro) phenyl) borate, tris (trifluoromethanesulfonyl) Mechidoion, bis (trifluoromethanesulfonyl) imide ion, hexafluoroantimonate ion, AsF ₆ ^- (hexafluoro arsenic acid ions), BF ₄ ^- (tetrafluoroborate), PF ₆ ^- (hexafluorophosphate) salts having a perfluoroalkyl anions such, such as salts with conjugate base of the protonic acid as an anion. Examples of the halogen _{compound, Cl 2, Br 2, I} 2, ICl, ICl 3, IBr, IF, etc .; Examples of the π-conjugated compound include TCNE (tetracyanoethylene) and TCNQ (tetracyanoquinodimethane). It is also possible to use the electron-accepting compounds described in JP-A-2000-36390, JP-A-2005-75948, JP-A-2003-213002, and the like. Preferred are Lewis acid, ionic compounds, π-conjugated compounds and the like.

The dopant used for n-type doping is an electron-donating compound, for example, an alkali metal such as Li, Cs; an alkaline earth metal such as Mg, Ca; an alkali metal such as LiF, Cs ₂ CO _3, and / or Alkaline earth metal salts; metal complexes; electron-donating organic compounds and the like.

When the charge-transporting polymer has a polymerizable functional group, it is preferable to use a compound that can act as a polymerization initiator for the polymerizable functional group as the dopant in order to facilitate the change in the solubility of the organic layer.

[Other optional ingredients]
The charge transporting material (organic electronics material) may further contain a charge transporting low molecular weight compound, another polymer, and the like.

[Content]
From the viewpoint of obtaining good charge transportability, the content of the charge transport polymer is preferably 50% by mass or more, more preferably 70% by mass or more, and 80% by mass or more, based on the total mass of the charge transport material. More preferred. It is also possible to make it 100% by mass.

When the dopant is contained, the content thereof is preferably 0.01% by mass or more, preferably 0.1% by mass, based on the total mass of the charge-transporting material from the viewpoint of improving the charge-transporting property of the charge-transporting material. The above is more preferable, and 0.5% by mass or more is further preferable. Further, from the viewpoint of maintaining good film-forming property, 50% by mass or less is preferable, 30% by mass or less is more preferable, and 20% by mass or less is further preferable with respect to the total mass of the charge transporting material.

<Ink composition>
The ink composition according to the embodiment of the present invention contains the charge transporting material of the embodiment and a solvent capable of dissolving or dispersing the material. By using the ink composition, the organic layer can be easily formed by a simple method such as a coating method.

[solvent]
As the solvent, water, an organic solvent, or a mixed solvent thereof can be used. Examples of the organic solvent include alcohols such as methanol, ethanol and isopropyl alcohol; alkanes such as pentane, hexane and octane; cyclic alkanes such as cyclohexane; aromatic hydrocarbons such as benzene, toluene, xylene, mesitylene, tetraline and diphenylmethane; ethylene glycol. Alibo ethers such as dimethyl ether, ethylene glycol diethyl ether, propylene glycol-1-monomethyl ether acetate; 1,2-dimethoxybenzene, 1,3-dimethoxybenzene, anisole, phenetol, 2-methoxytoluene, 3-methoxytoluene, Aromatic ethers such as 4-methoxytoluene, 2,3-dimethylanisole and 2,4-dimethylanisole; aliphatic esters such as ethyl acetate, n-butyl acetate, ethyl lactate and n-butyl lactate; phenyl acetate, propionic acid Aromatic esters such as phenyl, methyl benzoate, ethyl benzoate, propyl benzoate, n-butyl benzoate; amide solvents such as N, N-dimethylformamide, N, N-dimethylacetamide; dimethylsulfoxide, tetrahydrofuran, acetone , Chloroform, methylene chloride and the like. Aromatic hydrocarbons, aliphatic esters, aromatic esters, aliphatic ethers, aromatic ethers and the like are preferable.

[Polymerization initiator]
When the charge-transporting polymer has a polymerizable functional group, the ink composition preferably contains a polymerization initiator. As the polymerization initiator, known radical polymerization initiators, cationic polymerization initiators, anionic polymerization initiators and the like can be used. From the viewpoint that the ink composition can be easily prepared, it is preferable to use a substance having both a function as a dopant and a function as a polymerization initiator. Examples of such a substance include the ionic compound.

[Additive]
The ink composition may further contain an additive as an optional component. Additives include, for example, polymerization inhibitors, stabilizers, thickeners, gelling agents, flame retardants, antioxidants, antioxidants, oxidizing agents, reducing agents, surface modifiers, emulsifiers, defoamers, etc. Dispersants, surfactants and the like can be mentioned.

[Content]
The content of the solvent in the ink composition can be determined in consideration of application to various coating methods. For example, the content of the solvent is preferably such that the ratio of the charge transporting polymer to the solvent is 0.1% by mass or more, more preferably 0.2% by mass or more, and 0.5% by mass or more. Is more preferable. The content of the solvent is preferably such that the ratio of the charge-transporting polymer to the solvent is 20% by mass or less, more preferably 15% by mass or less, and further preferably 10% by mass or less. ..

<Organic layer>
The organic layer according to the embodiment of the present invention is a layer formed by using the charge transport material or the ink composition of the embodiment, and includes the charge transport material of the embodiment. By using the ink composition, the organic layer can be satisfactorily formed by the coating method. Examples of the coating method include a spin coating method; a casting method; a dipping method; a letterpress printing, a concave plate printing, an offset printing, a flat plate printing, a letterpress reversal offset printing, a screen printing, a plate printing method such as gravure printing; an inkjet method and the like. Known methods such as a plateless printing method can be mentioned. When the organic layer is formed by the coating method, the organic layer (coating layer) obtained after coating may be dried using a hot plate or an oven to remove the solvent.

When the charge-transporting polymer has a polymerizable functional group, the polymerization reaction of the charge-transporting polymer can be allowed to proceed by light irradiation, heat treatment, or the like, and the solubility of the organic layer can be changed. By stacking organic layers having different solubilities, it is possible to easily increase the number of layers of organic electronic devices. For the method of forming the organic layer, for example, the description of International Publication No. WO2010 / 1405553 can be referred to.

The thickness of the organic layer after drying or curing is preferably 0.1 nm or more, more preferably 1 nm or more, still more preferably 3 nm or more, from the viewpoint of improving the efficiency of charge transport. The thickness of the organic layer is preferably 300 nm or less, more preferably 200 nm or less, and further preferably 100 nm or less from the viewpoint of reducing the electric resistance.

<Organic electronics element>
The organic electronic device according to the embodiment of the present invention has at least one organic layer according to the embodiment. Examples of the organic electronics element include an organic EL element, an organic photoelectric conversion element, an organic transistor and the like. The organic electronics element preferably has a structure in which an organic layer is arranged between at least a pair of electrodes.

[Organic EL element]
The organic EL device according to the embodiment of the present invention has at least one organic layer according to the embodiment. The organic EL device usually includes a light emitting layer, an anode, a cathode, and a substrate, and if necessary, provides other functional layers such as a hole injection layer, an electron injection layer, a hole transport layer, and an electron transport layer. I have. Each layer may be formed by a vapor deposition method or a coating method. The organic EL device preferably has an organic layer as a light emitting layer or another functional layer, more preferably as a functional layer, and further preferably as at least one of a hole injection layer and a hole transport layer. Most preferably, it is provided as a hole injection layer.

FIG. 1 is a schematic cross-sectional view showing an embodiment of an organic EL device. The organic EL element of FIG. 1 is an element having a multi-layer structure, and includes a substrate 8, an anode 2, a hole injection layer 3 and a hole transport layer 6 composed of the organic layer of the above embodiment, a light emitting layer 1, and an electron transport layer 7. It has an electron injection layer 5 and a cathode 4 in this order. Hereinafter, each layer will be described.

[Light emitting layer]
As the material used for the light emitting layer, a light emitting material such as a low molecular weight compound, a polymer, or a dendrimer can be used. Polymers are preferred because they are highly soluble in solvents and suitable for coating methods. Examples of the light emitting material include a fluorescent material, a phosphorescent material, a heat-activated delayed fluorescent material (TADF), and the like.

Low molecular weight compounds such as perylene, coumarin, rubrene, quinacdrine, stilben, dye for dye laser, aluminum complex, and derivatives thereof as fluorescent materials; polyfluorene, polyphenylene, polyphenylene vinylene, polyvinylcarbazole, fluorene-benzothiazol copolymer , Fluorene-triphenylamine copolymers, polymers such as derivatives thereof; mixtures thereof and the like.

As the phosphorescent material, a metal complex containing a metal such as Ir or Pt can be used. Examples of the Ir complex include FIr (pic) (iridium (III) bis [(4,6-difluorophenyl) -pyridinate-N, C ² ] picolinate) that emits blue light, and Ir (ppy) ₃ that emits green light. (Factris (2-phenylpyridine) iridium), emits red light (btp) ₂ Ir (acac) (bis [2- (2'-benzo [4,5-α] thienyl) pyridinate-N, C ³ ] Iridium (acetyl-acetonate)), Ir (piq) ₃ (tris (1-phenylisoquinolin) iridium) and the like can be mentioned. Examples of the Pt complex include PtOEP (2, 3, 7, 8, 12, 13, 17, 18-octaethyl-21H, 23H-forfin platinum) that emits red light.

When the light emitting layer contains a phosphorescent material, it is preferable to further contain a host material in addition to the phosphorescent material. As the host material, a low molecular weight compound, a polymer, or a dendrimer can be used. Examples of low molecular weight compounds include CBP (4,4'-bis (9H-carbazole-9-yl) biphenyl), mCP (1,3-bis (9-carbazolyl) benzene), and CDBP (4,4'-. Bis (carbazole-9-yl) -2,2'-dimethylbiphenyl), derivatives thereof and the like, and as the polymer, the charge transporting material of the above-described embodiment, polyvinylcarbazole, polyphenylene, polyfluorene, derivatives thereof and the like can be used. Can be mentioned.

Examples of the heat-activated delayed fluorescent material include Adv. Mater., 21, 4802-4906 (2009); Appl. Phys. Lett., 98, 083302 (2011); Chem. Comm., 48, 9580 (2012). Appl. Phys. Lett., 101, 093306 (2012); J. Am. Chem. Soc., 134, 14706 (2012); Chem. Comm., 48, 11392 (2012); Nature, 492, 234 (2012) ); Adv. Mater., 25, 3319 (2013); J. Phys. Chem. A, 117, 5607 (2013); Phys. Chem. Chem. Phys., 15, 15850 (2013); Chem. Comm., 49, 10385 (2013); Chem. Lett., 43, 319 (2014) and the like.

[Hole injection layer, hole transport layer]
The organic layer formed by using the above-mentioned charge transporting material is preferably used as at least one of the hole injection layer and the hole transport layer, and more preferably at least as the hole injection layer. As described above, these layers can be easily formed by using an ink composition containing a charge transporting material.
When the organic EL device has an organic layer formed by using the above-mentioned charge transporting material as a hole transporting layer and further has a hole injecting layer, the hole injecting layer has a known material (triphenylamine). Etc.) can be used. Further, when the organic EL device has an organic layer formed by using the above charge transporting material as a hole injection layer and further has a hole transport layer, a known material is used for the hole transport layer. it can. It is also preferable to use the charge transporting material of the present embodiment for both the hole injection layer and the hole transport layer.

[Electron transport layer, electron injection layer]
Materials used for the electron transport layer and the electron injection layer include, for example, fused ring tetracarboxylic acid anhydrides such as phenanthroline derivative, bipyridine derivative, nitro-substituted fluorene derivative, diphenylquinone derivative, thiopyrandioxide derivative, naphthalene and perylene, and carbodiimide. , Fluolenilidene methane derivative, anthraquinodimethane and antron derivative, oxadiazole derivative, thiadiazole derivative, benzoimidazole derivative, quinoxalin derivative, aluminum complex and the like. In addition, the charge transporting material of the above embodiment can also be used.

[cathode]
As the cathode material, for example, a metal or a metal alloy such as Li, Ca, Mg, Al, In, Cs, Ba, Mg / Ag, LiF, CsF is used.

[anode]
As the anode material, for example, a metal (for example, Au) or another material having conductivity is used. Other materials include, for example, oxides (eg, ITO: indium oxide / tin oxide), conductive polymers (eg, polythiophene-polystyrene sulfonic acid mixture (PEDOT: PSS)).

[substrate]
Glass, plastic, etc. can be used as the substrate. The substrate is preferably transparent and preferably has flexibility. Quartz glass, light-transmitting resin film and the like are preferably used.
In one embodiment, the organic EL element preferably has a flexible substrate, and the flexible substrate preferably contains a resin film.

Examples of the resin film include films made of polyethylene terephthalate, polyethylene naphthalate, polyether sulfone, polyetherimide, polyetherether ketone, polyphenylene sulfide, polyarylate, polyimide, polycarbonate, cellulose triacetate, cellulose acetate propionate and the like. Can be mentioned.

When a resin film is used, the resin film may be coated with an inorganic substance such as silicon oxide or silicon nitride in order to suppress the permeation of water vapor, oxygen and the like.

[Sealing]
The organic EL element may be sealed in order to reduce the influence of the outside air and prolong the life. As the material used for sealing, a plastic film such as glass, epoxy resin, acrylic resin, polyethylene terephthalate or polyethylene naphthalate, or an inorganic substance such as silicon oxide or silicon nitride can be used, but the material is not limited thereto. Absent.
The sealing method is not particularly limited, and a known method can be used.

[Emission color]
The emission color of the organic EL element is not particularly limited. The white organic EL element is preferable because it can be used for various lighting fixtures such as household lighting, vehicle interior lighting, clocks, and liquid crystal backlights.

As a method for forming a white organic EL element, a method can be used in which a plurality of luminescent materials are used to simultaneously emit a plurality of luminescent colors to mix the colors. The combination of the plurality of emission colors is not particularly limited, but a combination containing three emission maximum wavelengths of blue, green and red, and a combination containing two emission maximum wavelengths such as blue and yellow, yellowish green and orange are used. Can be mentioned. The emission color can be controlled by adjusting the type and amount of the emission material.

<Display element, lighting device, display device>
The display element according to the embodiment of the present invention includes the organic EL element according to the embodiment. For example, a color display element can be obtained by using an organic EL element as an element corresponding to each pixel of red, green, and blue (RGB). There are two methods for forming an image: a simple matrix type in which individual organic EL elements arranged on a panel are directly driven by electrodes arranged in a matrix, and an active matrix type in which a thin film transistor is arranged and driven in each element.

Further, the lighting device according to the embodiment of the present invention includes the organic EL element according to the embodiment of the present invention. Further, the display device according to the embodiment of the present invention includes a lighting device and a liquid crystal element as a display means. For example, the display device can be a display device using a lighting device according to an embodiment of the present invention as a backlight and a known liquid crystal element as a display means, that is, a liquid crystal display device.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples. Unless otherwise specified, "%" means "mass%".

<1> Preparation of charge-transporting polymer (preparation of Pd catalyst)
Tris (dibenzylideneacetone) dipalladium (73.2 mg, 80 μmol) was weighed in a sample tube at room temperature in a glove box under a nitrogen atmosphere, anisole (15 ml) was added, and the mixture was stirred for 30 minutes. Similarly, tris (t-butyl) phosphine (129.6 mg, 640 μmol) was weighed into a sample tube, anisole (5 ml) was added, and the mixture was stirred for 5 minutes. These solutions were mixed and stirred at room temperature for 30 minutes to give a catalyst solution. In the preparation of the catalyst, all the solvents were used after being degassed by nitrogen bubbles for 30 minutes or more.

(Preparation Example 1-Charge Transporting Polymer 1)
The charge transport polymer 1 was prepared as follows.
The following monomer 1 (4.0 mmol), the following monomer 2 (5.0 mmol), the following monomer 3 (2.0 mmol), and anisole (20 ml) were added to the three-necked round-bottom flask, and the Pd catalyst prepared separately was added. The solution (7.5 ml) was added and stirred. After stirring for 30 minutes, a 10% tetraethylammonium hydroxide aqueous solution (20 ml) was added to the flask. The mixture was heated to reflux for 2 hours. All the operations up to this point were performed under a nitrogen stream. In addition, all solvents were used after being degassed by nitrogen bubbles for 30 minutes or more.

After completion of the reaction, the organic layer was washed with water. The organic layer was then poured into methanol-water (9: 1). The resulting precipitate was suction filtered and washed with methanol-water (9: 1). The washed precipitate was dissolved in toluene and reprecipitated from methanol. The obtained precipitate is suction-filtered, then dissolved in toluene, and Triphenylphosphine, polymer-bound on styrene-divinylbenzene copolymer (Strem Chemicals, 200 mg per 100 mg of polymer, hereinafter referred to as "metal adsorbent") is added. Stirred overnight.
After the stirring was completed, the metal adsorbent and the insoluble matter were removed by filtration, and the filtrate was concentrated on a rotary evaporator. The concentrate was dissolved in toluene and then reprecipitated from methanol-acetone (8: 3). The resulting precipitate was suction filtered and washed with methanol-acetone (8: 3). The obtained precipitate was vacuum dried to obtain a charge transport polymer 1.
The obtained charge-transporting polymer 1 had a number average molecular weight of 7,800 and a mass average molecular weight of 31,000.

The number average molecular weight and the mass average molecular weight were measured by GPC (polystyrene conversion) using tetrahydrofuran (THF) as an eluent. The measurement conditions are as follows.
Liquid transfer pump: L-6050 Hitachi High-Technologies Corporation UV-Vis detector: L-3000 Hitachi High-Technologies Corporation Column: Gelpack (registered trademark) GL-A160S / GL-A150S Hitachi Chemical Co., Ltd.
Eluent: THF (for HPLC, no stabilizer included) Wako Pure Chemical Industries, Ltd.
Flow velocity: 1 ml / min
Column temperature: Room temperature Molecular weight standard substance: Standard polystyrene

(Preparation Example 2-Charge Transporting Polymer 2)
The charge transporting polymer 2 was prepared as follows.
Monomer 2 (5.0 mmol) and monomer 3 (2.0 mmol) described in Preparation Example 1, the following monomer 4 (4.0 mmol), and anisole (20 ml) are added to a three-necked round-bottom flask, and further prepared separately. A solution of the Pd catalyst (7.5 ml) was added, and the mixture was stirred. After that, the charge transporting polymer 2 was prepared in the same manner as described in Preparation Example 1. The obtained charge-transporting polymer 2 had a number average molecular weight of 22,900 and a mass average molecular weight of 169,000.

(Preparation Example 3-Charge Transporting Polymer 3)
The charge-transporting polymer 3 was prepared in the same manner as in Preparation Example 1 except that the monomer 1 (4.0 mmol) was changed to the monomer 1 (1.0 mmol) and the following monomer 5 (3.0 mmol).
The obtained charge-transporting polymer 3 had a number average molecular weight of 13,384 and a mass average molecular weight of 63,790.

(Preparation Example 4-Charge Transporting Polymer 4)
The charge-transporting polymer 4 was prepared in the same manner as in Preparation Example 1 except that the monomer 1 (4.0 mmol) was changed to the monomer 1 (1.0 mmol) and the following monomer 6 (3.0 mmol). The obtained charge-transporting polymer 4 had a number average molecular weight of 12,757 and a mass average molecular weight of 68,501.

(Preparation Example 5-Charge Transporting Polymer 5)
The charge-transporting polymer 5 was prepared in the same manner as in Preparation Example 1 except that the monomer 1 (4.0 mmol) was changed to the monomer 1 (1.0 mmol) and the following monomer 7 (3.0 mmol). The obtained charge-transporting polymer 5 had a number average molecular weight of 10,959 and a mass average molecular weight of 69,631.

(Preparation Example 6-Charge Transport Polymer 6)
The charge-transporting polymer 6 was prepared in the same manner as in Preparation Example 1 except that the monomer 1 (4.0 mmol) was changed to the monomer 1 (1.0 mmol) and the following monomer 8 (3.0 mmol). The obtained charge-transporting polymer 6 had a number average molecular weight of 14,587 and a mass average molecular weight of 68,111.

(Preparation Example 7-Charge Transport Polymer 7)
The charge-transporting polymer 7 was prepared in the same manner as in Preparation Example 1 except that the monomer 1 (4.0 mmol) was changed to the monomer 1 (1.0 mmol) and the following monomer 9 (3.0 mmol). The obtained charge-transporting polymer 7 had a number average molecular weight of 7,522 and a mass average molecular weight of 43,238.

(Preparation Example 8-Charge Transporting Polymer 8)
The charge-transporting polymer 8 was prepared in the same manner as in Preparation Example 3 except that the monomer 3 (2.0 mmol) was changed to the following monomer 10 (2.0 mmol). The obtained charge-transporting polymer 8 had a number average molecular weight of 18,522 and a mass average molecular weight of 76,471.

(Preparation Example 9-Charge Transport Polymer 9)
The charge-transporting polymer 9 was prepared in the same manner as in Preparation Example 4 except that the monomer 3 (2.0 mmol) was changed to the following monomer 10 (2.0 mmol). The obtained charge-transporting polymer 9 had a number average molecular weight of 13,887 and a mass average molecular weight of 64,613.

(Preparation Example 10-Charge Transport Polymer 10)
The charge-transporting polymer 10 was prepared in the same manner as in Preparation Example 5 except that the monomer 3 (2.0 mmol) was changed to the following monomer 10 (2.0 mmol). The obtained charge-transporting polymer 9 had a number average molecular weight of 8,709 and a mass average molecular weight of 37,657.

(Preparation Example 11-Charge Transport Polymer 11)
The charge-transporting polymer 11 was prepared in the same manner as in Preparation Example 3 except that the monomer 3 (2.0 mmol) was changed to the following monomer 11 (2.0 mmol). The obtained charge-transporting polymer 11 had a number average molecular weight of 12,135 and a mass average molecular weight of 62,780.

(Preparation Example 12-Charge Transport Polymer 12)
The charge-transporting polymer 12 was prepared in the same manner as in Preparation Example 4 except that the monomer 3 (2.0 mmol) was changed to the following monomer 11 (2.0 mmol). The obtained charge-transporting polymer 12 had a number average molecular weight of 11,358 and a mass average molecular weight of 59,976.

(Preparation Example 13-Charge Transport Polymer 13)
The charge transport polymer 13 was prepared in the same manner as in Preparation Example 5 except that the monomer 3 (2.0 mmol) was changed to the following monomer 11 (2.0 mmol). The obtained charge-transporting polymer 13 had a number average molecular weight of 10,743 and a mass average molecular weight of 82,412.

The monomers 5 to 11 are collectively shown below.

The thermogravimetric reduction of each charge transport polymer when heated at 300 ° C. is shown below.
To reduce the thermogravimetric analysis, use a TG-DTA measuring device (DTG-60H manufactured by Shimadzu Corporation) to measure the thermogravimetric reduction ratio when 10 mg of the polymer is heated to 300 ° C. in air under a heating condition of 5 ° C./min. It was obtained by measuring.

<2-1> Fabrication of Organic HOD Element (Example 1)
The charge-transporting polymer 3 (10.0 mg) obtained by synthesizing the above-mentioned charge-transporting polymer and the following ionic compound 1 (0.5 mg) on a glass substrate in which ITO is patterned to a width of 1.6 mm under a nitrogen atmosphere. The ink composition consisting of, and toluene (2.3 ml) was spin-coated at 3000 min ^-1 , and then heated and cured in the air at 200 ° C. for 30 minutes on a hot plate to form a hole injection layer (100 nm). The formed substrate was heated in the air at 200 ° C. for 30 minutes, and then heated in nitrogen at 230 ° C. for 30 minutes to be cured to prepare a substrate on which a hole injection layer (100 nm) was formed.

The substrate obtained above is transferred to a vacuum vapor deposition machine, and α-NPD (20 nm) and Al (100 nm) are deposited on the hole injection layer in this order by a vapor deposition method, and sealed to perform organic HOD (organic HOD). Hole only device) The element was manufactured.

(Examples 2 to 11, Comparative Example 1)
In Example 1, an ink composition obtained by changing the charge-transporting polymer 3 in the ink composition used for forming the hole injection layer in the organic EL device to each charge-transporting polymer shown in Table 2 below. Each was prepared. The organic HOD devices of Examples 2 to 11 and Comparative Example 1 were produced in the same manner as in Example 1 except that the hole injection layer was formed using this ink composition.

<2-2> Evaluation of HOD element When a voltage is applied to the organic HOD elements obtained in Examples 1 to 11 and Comparative Example 1, it is found that a current flows in each of them, and it has a hole injecting function. confirmed. For each element, the drive voltage at a current density of 300 mA / cm was measured. The measurement results are shown in Table 2.

As shown in the table, the organic HOD elements of Examples 1 to 11 showed less increase in drive voltage due to additional heating at 230 ° C./30 minutes than in Comparative Example 1, and showed a result that a low drive voltage could be maintained. .. That is, from the viewpoint of the constituent materials of the hole injection layer, hole injection in a high temperature process is performed by using a charge transport polymer having low thermogravimetric reduction and improved heat resistance as the charge transport material. It can be seen that the effect of maintaining sexuality can be obtained.

<3-1> Fabrication of Organic EL Element (Example 12)
The charge-transporting polymer 3 (10.0 mg) obtained by synthesizing the above-mentioned charge-transporting polymer and the above-mentioned ionic compound 1 (0.5 mg) on a glass substrate in which ITO is patterned to a width of 1.6 mm under a nitrogen atmosphere. ) And toluene (2.3 mL) are spin-coated at 3000 min ^-1 and then heated on a hot plate at 200 ° C. for 30 minutes, 230 ° C. for 30 minutes to cure, and the hole injection layer. (30 nm) was formed.

Next, the ink composition composed of the charge-transporting polymer 2 (20 mg) and toluene (2.3 mL) obtained above was spin-coated on the hole injection layer obtained by the above operation at 3000 min ^-1. , Heated on a hot plate at 180 ° C. for 10 minutes and dried to form a hole transport layer (40 nm). The hole transport layer could be formed without dissolving the hole injection layer.

The substrate obtained above is transferred into a vacuum vapor deposition machine, and CBP: Ir (ppy) ₃ (94: 6, 30 nm), BAlq (10 nm), Alq ₃ (30 nm), LiF (0) are placed on the hole transport layer. A film was formed in the order of 0.8 nm) and Al (100 nm) by a vapor deposition method, and a sealing treatment was performed to prepare an organic EL device.

(Examples 13 to 22, Comparative Example 2)
In Example 12, an ink composition obtained by changing the charge-transporting polymer 3 in the ink composition used for forming the hole injection layer in the organic EL device to each charge-transporting polymer shown in Table 3 below. Each was prepared. The organic EL devices of Examples 13 to 22 and Comparative Example 2 were produced in the same manner as in Example 12 except that the hole injection layer was formed using this ink composition.

<3-2> Evaluation of Organic EL Element When a voltage was applied to the organic EL elements obtained in Examples 12 to 22 and Comparative Example 2, green light emission was confirmed in both cases. For each element, emission luminance 5000 cd / ^{m 2} at the drive voltage and luminous efficiency were measured emission lifetime (luminance half-life) in an initial luminance 5000 cd / ^{m 2.} The measurement results are shown in Table 3.

As shown in the table, the organic EL devices of Examples 12 to 22 were superior in luminous efficiency and showed a longer emission lifetime than those of Comparative Example 2. That is, from the viewpoint of the constituent materials of the hole injection layer, by using a charge-transporting polymer having a small thermogravimetric reduction as the charge-transporting material, high-temperature heating is possible, and the luminous efficiency and the luminous life are reduced. It can be seen that effects such as improvement can be obtained.

As described above, the effects of the embodiments of the present invention are shown by the examples. However, according to the present invention, the organic electronics are not limited to the charge-transporting polymer used in the examples, and even when other charge-transporting polymers are used as long as they do not deviate from the scope of the present invention. It is possible to obtain an element. The obtained organic electronic device has excellent characteristics as in each of the above embodiments.

1 Light emitting layer 2 Anode 3 Hole injection layer 4 Cathode 5 Electron injection layer 6 Hole transport layer 7 Electron transport layer 8 Substrate

Claims (13)

Contains a charge-transporting polymer with a thermogravimetric loss of 5% by mass or less when heated at 300 ° C.
The charge-transporting polymer has at least a divalent structural unit having a charge-transporting property and a monovalent structural unit constituting the terminal portion, and does not have a cross-linking group or another substituent at the 4'-position. Does not contain N- (4-biphenyl) structure,
The divalent structural unit comprises one or more structures selected from the group consisting of an aromatic amine structure, a carbazole structure, and an N-arylphenoxazine structure.
The monovalent structural units, a monovalent structural units containing polycyclic structure based on polycyclic aromatic hydrocarbons and / or aromatic amines, seen containing 50 mol% or more of all monovalent structural units based , The polycyclic aromatic hydrocarbon contains pyrene, and the aromatic amine contains a triarylamine , a charge-transporting material. The charge-transporting material according to claim 1 , wherein the charge-transporting polymer has at least one polymerizable functional group. The charge-transporting polymer, bifurcation and further have a trivalent or more structural units that constitute the, the trivalent or more structural units, aromatic amine structure, a group consisting of carbazole structure, and N- aryl phenoxazine structure The charge transporting material according to claim 1 or 2 , which comprises one or more structures selected from . The charge transporting material according to any one of claims 1 to 3 , which is used as a hole injecting material. An ink composition comprising the charge transporting material according to any one of claims 1 to 4 and a solvent. An organic layer formed by using the charge transporting material according to any one of claims 1 to 4 or the ink composition according to claim 5 . An organic electronic device having at least one organic layer according to claim 6 . An organic electroluminescent device having at least one organic layer according to claim 6 . The organic electroluminescence device according to claim 8 , further comprising a flexible substrate. The organic electroluminescence device according to claim 9 , wherein the flexible substrate contains a resin film. A display device including the organic electroluminescence device according to any one of claims 8 to 10 . A lighting device comprising the organic electroluminescence element according to any one of claims 8 to 10 . A display device including the lighting device according to claim 12 and a liquid crystal element as a display means.

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