JP2023178859A - Organic electronic material and organic electronic device - Google Patents

Abstract

To provide an organic electronic material that can be cured at a low temperature.SOLUTION: An organic electronics material includes an ionic compound containing diphenylmethylammonium, and a charge transporting polymer having an oxetanyl group.SELECTED DRAWING: None

Description

The present disclosure relates to an organic electronic material, an ink composition, an organic layer, an organic electronic element, an organic electroluminescent element (organic EL element), a display element, a lighting device, and a display device.

Organic electronic devices are devices that perform electrical operations using organic substances, and are expected to exhibit features such as energy saving, low cost, and flexibility. Examples of organic electronic devices include organic EL devices, organic photoelectric conversion devices, organic transistors, and the like.

These organic electronic devices are desired to be further improved in various device characteristics. For example, as a means of improving the performance of organic EL elements, attempts have been made to multilayer organic layers and separate the functions of each layer. When forming multiple layers by a wet process, the lower layer is required to have solvent resistance with respect to the solvent of the coating liquid used when forming the upper layer.

In order to make the organic layer multilayer, for example, a method using a compound having at least one polymerizable group is being considered (see, for example, Patent Document 1).

Japanese Patent Application Publication No. 2006-279007

The present disclosure provides organic electronic materials that can be cured at low temperatures and ink compositions containing the organic electronic materials. The present disclosure also provides an organic layer with excellent solvent resistance, and an organic electronic device, an organic EL device, a display device, a lighting device, and a display device including the organic layer.

This disclosure includes various embodiments of the invention. Examples of embodiments are listed below. The present invention is not limited to the following embodiments.

(1) An organic electronics material containing an ionic compound containing diphenylmethylammonium and a charge transporting polymer having an oxetanyl group.
(2) The organic electronics material according to (1) above, wherein the ionic compound contains a substituted or unsubstituted tetrakis(aryl)boron anion.
(3) The organic electronics material according to (1) or (2) above, wherein the ionic compound includes diphenylmethylammonium tetrakis(pentafluorophenyl)borate.
(4) The charge transporting polymer has a structural unit containing at least one structure selected from the group consisting of an aromatic amine structure, a carbazole structure, a thiophene structure, a benzene structure, a pyrrole structure, a furan structure, and a fluorene structure. The organic electronic material according to any one of (1) to (3) above.
(5) The organic electronic material according to any one of (1) to (4) above, wherein the charge transporting polymer has a structural unit containing an aromatic amine structure.
(6) The organic electronic material according to any one of (1) to (5) above, wherein the charge transporting polymer has a structural unit containing an aromatic amine structure substituted with a fluoro group.
(7) The organic electronic material according to any one of (1) to (6) above, wherein the charge transporting polymer includes a branched polymer.
(8) An ink composition containing the organic electronics material according to any one of (1) to (7) above and a solvent.
(9) An organic layer formed using the organic electronic material according to any one of (1) to (7) above or the ink composition according to (8) above.
(10) An organic electronic device comprising the organic layer described in (9) above.
(11) An organic electroluminescent device having the organic layer described in (9) above.
(12) A display element comprising the organic electroluminescent element according to (11) above.
(13) A lighting device comprising the organic electroluminescent element according to (11) above.
(14) A display device comprising the organic electroluminescent element according to (11) above.
(15) A display device comprising the lighting device according to (13) above and a liquid crystal element as a display means.

According to the present disclosure, it is possible to obtain an organic electronic material that can be cured at low temperatures and an ink composition containing the organic electronic material. Further, according to the present disclosure, it is possible to obtain an organic layer having excellent solvent resistance, and an organic electronic device, an organic EL device, a display device, a lighting device, and a display device including the organic layer.

Embodiments of the present invention will be described. The present invention is not limited to the following embodiments. Embodiments of the present invention will be described. The present invention is not limited to the following embodiments. Moreover, the following embodiments can be implemented alone or in combination. Combinations of multiple embodiments are also included in the present invention.

In the numerical ranges described step by step in this disclosure, the upper limit or lower limit described in one numerical range may be replaced with the upper limit or lower limit of another numerical range. Further, the upper limit or lower limit of the numerical range described in this disclosure may be replaced with the value shown in the Examples. A certain numerical value may be selected from the upper limit numerical value and the lower limit numerical value which are described in stages in this disclosure to form a stepwise numerical range. Further, the upper limit numerical values and lower limit numerical values described in this disclosure may be replaced with the values shown in the examples.
In the present disclosure, each component may contain multiple types of applicable substances. If there are multiple types of substances corresponding to each component in the composition, the content rate or content of each component is the total content rate or content of the multiple types of substances present in the composition, unless otherwise specified. means quantity.
In the present disclosure, each structure in the polymer may include multiple types of corresponding structures. If multiple types of structures corresponding to each structure exist in the polymer, the content rate or content of each structure is the total content rate or content of the multiple types of structures present in the polymer, unless otherwise specified. means.
In the present disclosure, "layer" includes continuous layers and discontinuous layers. The thickness of a "layer" may be uniform or non-uniform. The outer edge in the plane direction and the outer edge in the thickness direction of the "layer" may be clear or unclear, respectively. The same applies to the "membrane".

<Organic electronics materials>
An organic electronic material that is an embodiment of the present invention contains an ionic compound containing diphenylmethylammonium and a charge transporting polymer having an oxetanyl group.

[Ionic compound]
The ionic compound includes diphenylmethylammonium and an anion. Ionic compounds usually contain diphenylmethylammonium and an anion such that their charges are balanced. It is thought that when an ionic compound containing diphenylmethylammonium is used as a polymerization initiator, the formation of a proton adduct of an oxetanyl group proceeds easily, making it possible to cure the charge transporting polymer at a low temperature.

Diphenylmethylammonium is a cation represented by the following formula.

Examples of the anion include anions represented by the following formulas (1A) to (5A).

[In the formula, E ¹ is an oxygen atom, E ² is a nitrogen atom, E ³ is a carbon atom, E ⁴ is a boron atom or a gallium atom, E ⁵ is a phosphorus atom or an antimony atom, and Y ¹ to Y ⁶ are each Each of R ¹ to R ¹⁶ independently represents a single bond or a divalent linking group, and each of R 1 to R 16 independently represents an electron-withdrawing monovalent group (at least two selected from R ² and R ³ and R ⁴ to R ⁶ at least two groups selected from R ⁷ to R ¹⁰ and at least two groups selected from R ¹¹ to R ¹⁶ may each be bonded to each other. ]

In formulas (1A) to (5A), R ¹ to R ¹⁶ each independently represent an electron-withdrawing monovalent group. An electron-withdrawing monovalent group refers to a substituent that more easily attracts electrons from the bonding atom side than a hydrogen atom. R ¹ to R ¹⁶ are preferably organic groups. An organic group refers to an atomic group having one or more carbon atoms. The same applies below for organic groups. R ² and R ³ , at least two groups selected from R ⁴ to R ⁶ , at least two groups selected from R ⁷ to R ¹⁰ , and at least two groups selected from R ¹¹ to R ¹⁶ are , may be connected to each other. The bonded group may be cyclic.

Examples of electron-withdrawing monovalent groups include halogen atoms such as fluorine atoms, chlorine atoms, and bromine atoms; cyano groups; thiocyano groups; nitro groups; alkylsulfonyl groups such as mesyl groups (for example, carbon atoms of 1 to 12 , preferably 1 to 6 carbon atoms); Arylsulfonyl groups such as tosyl group (for example, 6 to 18 carbon atoms, preferably 6 to 12 carbon atoms); Alkyloxysulfonyl groups such as methoxysulfonyl group (for example, 1 to 12 carbon atoms); , preferably 1 to 6 carbon atoms); aryloxysulfonyl groups such as phenoxysulfonyl groups (for example, 6 to 18 carbon atoms, preferably 6 to 12 carbon atoms); acyl groups such as formyl, acetyl, and benzoyl groups (for example, (1 to 12 carbon atoms, preferably 1 to 6 carbon atoms); Acyloxy groups such as formyloxy group and acetoxy group (for example, 1 to 20 carbon atoms, preferably 1 to 6 carbon atoms); methoxycarbonyl group, ethoxycarbonyl group, etc. alkoxycarbonyl group (for example, carbon number 2 to 10, preferably carbon number 2 to 7); "aryloxycarbonyl group or heteroaryloxycarbonyl group" such as phenoxycarbonyl group, pyridyloxycarbonyl group (for example, carbon number 4 to 25) , preferably 5 to 15 carbon atoms); ``haloalkyl group'' in which a halogen atom is substituted for a linear, branched, or cyclic ``alkyl group, alkenyl group, or alkynyl group'' such as a trifluoromethyl group or a pentafluoroethyl group; , haloalkenyl group or haloalkynyl group (for example, carbon number 1 to 10, preferably carbon number 1 to 6); haloaryl group in which an aryl group such as pentafluorophenyl group is substituted with a halogen atom (for example, carbon number 6 to 20, (preferably 6 to 12 carbon atoms); haloarylalkyl groups (eg, 7 to 19 carbon atoms, preferably 7 to 13 carbon atoms) in which an arylalkyl group such as a pentafluorophenylmethyl group is substituted with a halogen atom; and the like.

In formulas (1A) to (5A), Y ¹ to Y ⁶ each independently represent a single bond or a divalent linking group. When Y ¹ to Y ⁶ are single bonds, it means that E and R are directly bonded. Examples of the divalent linking group include linking groups represented by any of the following formulas (1c) to (11c).

[In the formula, R each independently represents a hydrogen atom or a monovalent group. ]

Preferably, R is an organic group. From the viewpoint of improving electron acceptability, solubility in a solvent, etc., each R is preferably an alkyl group, an alkenyl group, an alkynyl group, an aryl group, or a heteroaryl group. These groups may have a substituent or a heteroatom. Further, R is preferably an electron-withdrawing monovalent group, and examples of the electron-withdrawing monovalent group include the above-mentioned electron-withdrawing monovalent group.

As the anion, an anion in which the negative charge is mainly on an oxygen atom, a nitrogen atom, a carbon atom, a boron atom, or a gallium atom is preferable, and an anion in which the negative charge is mainly on an oxygen atom, a nitrogen atom, a carbon atom, or a boron atom is more preferable. Examples include anions represented by any of formulas (6A) to (9A).

[In the formula, R ¹ to R ¹⁰ are each independently an electron-withdrawing monovalent group (R ² and R ³ , at least two groups selected from R ⁴ to R ⁶ , and R ⁷ to R At least two groups selected from ¹⁰ may each be bonded to each other. ]

R ¹ to R ¹⁰ are preferably organic groups. Examples of the electron-withdrawing monovalent group include the above-mentioned electron-withdrawing monovalent group.

From the viewpoint of charge transportability, the anion preferably includes an anion represented by formula (9A), and preferably includes a tetrakis(aryl)boron anion. The aryl groups in the tetrakis(aryl)boron anion may each independently be substituted or unsubstituted.

An aryl group is an atomic group obtained by removing one hydrogen atom from an aromatic hydrocarbon. The aromatic hydrocarbon herein is selected from the group consisting of a single ring, a condensed ring, and a polycycle in which two or more rings selected from the monocycle and condensed rings are bonded together through chemical bonds. Aromatic hydrocarbons are, for example, selected from the group consisting of benzene, naphthalene, anthracene, tetracene, fluorene, phenanthrene, 9,10-dihydrophenanthrene, triphenylene, pyrene, chrysene, perylene, triphenylene, pentacene, and benzopyrene. The aromatic hydrocarbon may be benzene, naphthalene, fluorene, anthracene, or phenanthrene; it may be benzene or naphthalene; it may be benzene.

The "substituents" that the substituted aryl group may have include, for example, alkyl groups, alkenyl groups, alkynyl groups, aryl groups, heteroaryl groups, arylalkyl groups, heteroarylalkyl groups, alkylaryl groups, and alkylheteroaryl groups. , halogen group, nitro group, cyano group, amino group, silyl group, sulfo group, hydroxyl group, mercapto group, formyl group, carboxyl group, alkoxy group, aryloxy group, heteroaryloxy group, alkylthio group, arylthio group, hetero It contains at least one selected from the group consisting of an arylthio group, an acyl group, an acyloxy group, and an alkyloxycarbonyl group. These "substituents" may be substituted or unsubstituted "substituents", and the "substituents" that the substituted "substituents" may have include, for example, at least one kind selected from the above group. may include. The substituted aryl group is preferably a halogen-substituted aryl group, more preferably a fluoroaryl group, and even more preferably a perfluoroaryl group. In the present disclosure, examples of the halogen group include a fluoro group, a chloro group, a bromo group, an iodo group, and the like.

The ionic compound preferably contains diphenylmethylammonium tetrakis(pentafluorophenyl)borate represented by the following formula from the viewpoint of low temperature curability and device properties.

[Charge transporting polymer]
The charge transporting polymer has oxetanyl groups. The charge transporting polymer exhibits curability due to having an oxetanyl group (oxetane group). By curing a coating film containing a charge transporting polymer to form an organic layer, it is possible to provide the organic layer with the solvent resistance necessary for laminating the upper layer by a wet process. In the present disclosure, a layer before curing that is formed using an organic electronics material and contains a charge transporting polymer and an ionic compound may be referred to as a coating film. In the present disclosure, the term "polymer" also includes so-called "oligomers" having a small number of structural units. According to an organic electronic material containing a charge transporting polymer having an oxetanyl group and an ionic compound containing diphenylmethylammonium, an organic layer having good solvent resistance even when cured in a low temperature region can be formed. Can be formed. Furthermore, even when cured in a low temperature range, the resulting organic layer tends to have high conductivity.

For example, when a charge-transporting polymer having an oxetanyl group is used to form the hole-transporting layer, the hole-transporting layer becomes a layer having solvent resistance. This makes it possible to form a light emitting layer as an upper layer using an ink composition or the like while preventing the hole transport layer from dissolving. Generally, the light-emitting layer is often coated with an aromatic hydrocarbon solvent. Therefore, in this example, the charge transporting polymer having an oxetanyl group is preferably a charge transporting polymer that can form a charge transporting layer that is difficult to dissolve even when immersed in an aromatic hydrocarbon solvent such as toluene.

The oxetanyl group may be a substituted or unsubstituted oxetanyl group, and examples of substituents that the oxetanyl group may have include alkyl groups having 1 to 6 carbon atoms such as methyl group and ethyl group.

The charge transporting polymer preferably contains a structural unit containing at least one structure selected from the group consisting of an aromatic amine structure, a carbazole structure, a thiophene structure, a benzene structure, a pyrrole structure, a furan structure, and a fluorene structure. . By including any one of these structures, charge transport properties, particularly hole transport properties, are improved. In preferred embodiments, the charge transporting polymer includes structural units that include aromatic amine structures. More preferably, the charge transporting polymer has a structural unit containing an aromatic amine structure substituted with a fluoro group.

In some embodiments, the structural unit containing an aromatic amine structure is a structural unit represented by the following formula (1), a structural unit represented by the following formula (2-1), and a structural unit represented by the following formula (2-2). ) contains at least one structural unit selected from the group consisting of structural units represented by: In the present disclosure, the "structural unit represented by formula (1)" may be referred to as "structural unit (1)." "At least one structural unit selected from the group consisting of the structural unit represented by formula (2-1) and the structural unit represented by formula (2-2)" is referred to as "structural unit (2)". There are cases.

In the formula, Ar each independently represents a substituted or unsubstituted aromatic hydrocarbon group. At least one Ar may be an aromatic hydrocarbon group having a substituent containing at least one selected from the group consisting of a fluoro group and a fluoroalkyl group.

Regarding the aromatic hydrocarbon in the aromatic hydrocarbon group, the explanation regarding the aromatic hydrocarbon in the ionic compound can be applied.

Ar is each independently preferably a substituted or unsubstituted benzene group, a substituted or unsubstituted naphthalene group, or a substituted or unsubstituted anthracene group; More preferably, it is an unsubstituted naphthalene group.

The aromatic hydrocarbon group may have a substituent. Examples of the substituent include a substituent selected from the group consisting of -R ¹ , -OR ² , -SR ³ , -OCOR ⁴ , -COOR ⁵ , -SiR ⁶ R ⁷ R ⁸ , and a halogen group (hereinafter referred to as , may be written as "substituent Ra").

R ¹ is, for example, selected from the group consisting of an alkyl group, an aryl group, and a heteroaryl group. R ² to R ⁸ are, for example, each independently selected from the group consisting of a hydrogen atom, an alkyl group, an aryl group, and a heteroaryl group. The alkyl group, aryl group, and heteroaryl group are as described above.

The alkyl group, aryl group, and heteroaryl group may have a substituent. When the alkyl group, aryl group, and heteroaryl group has a substituent, examples of the substituent include the above-mentioned substituent Ra, preferably -R ¹ . Examples of the alkyl group having a substituent include an arylalkyl group, a heteroarylalkyl group, a fluoroalkyl group, and the like. Examples of the aryl group having a substituent include an alkylaryl group and a fluoroaryl group. Examples of the heteroaryl group having a substituent include an alkylheteroaryl group and the like.

In structural unit (1), at least one Ar may be an aromatic hydrocarbon group having a substituent containing at least one selected from the group consisting of a fluoro group and a fluoroalkyl group. The fluoroalkyl group may have 1 to 4 carbon atoms, preferably 1 or 2 carbon atoms. The fluoroalkyl group is preferably a perfluoroalkyl group.

For example, from the viewpoint of achieving both a deep HOMO level and a large energy gap between HOMO and LUMO, in the structural unit (1), at least one Ar is an aromatic hydrocarbon group having a fluoro group, and all Ar may be an aromatic hydrocarbon group having no fluoroalkyl group.

For example, from the viewpoint of obtaining a deeper HOMO level, at least one Ar in structural unit (1) may be an aromatic hydrocarbon group having a fluoroalkyl group.

The total number of fluoro groups or fluoroalkyl groups contained in the structural unit (1) is, for example, 1 to 8, 1 to 6, 1 to 4, or 1 to 3. In the case of the above number, there is a tendency that the effect of deepening the HOMO level can be easily obtained. When the number is within the above range, it tends to be easy to prevent the solubility of the charge transporting polymer from becoming too low.

The structural unit (1) includes, for example, a structural unit represented by the following formula (1a).

In the formula, each R independently represents a hydrogen atom or a substituent, and at least one R is a fluoro group or a fluoroalkyl group.

The number of carbon atoms in the fluoroalkyl group is, for example, 1 to 4, preferably 1 or 2. The fluoroalkyl group is preferably a perfluoroalkyl group. In the formula, the number of R's that are fluoro groups or fluoroalkyl groups is, for example, 1 to 8, 1 to 6, 1 to 4, or 1 to 3.

R that is not a fluoro group or a fluoroalkyl group is a hydrogen atom or a substituent. Examples of the substituent include the substituent Ra (excluding fluoro groups and fluoroalkyl groups here). From the viewpoint of suppressing the influence of substituents, all of R that is not a fluoro group or a fluoroalkyl group may be a hydrogen atom.

In the formula, Ar each independently represents a substituted or unsubstituted aromatic hydrocarbon group. At least one Ar may be an aromatic hydrocarbon group having a substituent containing at least one selected from the group consisting of a fluoro group and a fluoroalkyl group.

In the formula, Ar each independently represents a substituted or unsubstituted aromatic hydrocarbon group. At least one Ar may be an aromatic hydrocarbon group having a substituent containing at least one selected from the group consisting of a fluoro group and a fluoroalkyl group.

Regarding the substituted or unsubstituted aromatic hydrocarbon group, the explanation regarding the substituted or unsubstituted aromatic hydrocarbon group in the structural unit (1) above can be applied. Ar is preferably an unsubstituted aromatic hydrocarbon group.

In the structural unit (2-1), each Ar is preferably a substituted or unsubstituted benzene group, a substituted or unsubstituted naphthalene group, or a substituted or unsubstituted anthracene group; It is more preferably a substituted benzene group or a substituted or unsubstituted naphthalene group, and even more preferably a substituted or unsubstituted benzene group.

In the structural unit (2-2), Ar is each independently preferably a substituted or unsubstituted benzene group, a substituted or unsubstituted naphthalene group, or a substituted or unsubstituted anthracene group; It is more preferably a substituted benzene group or a substituted or unsubstituted naphthalene group, and even more preferably a substituted or unsubstituted benzene group.

The structural unit (2) includes, for example, at least one type of structural unit selected from the group consisting of structural units represented by the following formula (2-1a) and the following formula (2-2a).

In the formula, each R independently represents a hydrogen atom or a substituent. An example of the substituent is the aforementioned substituent Ra.

In the formula, each R independently represents a hydrogen atom or a substituent. An example of the substituent is the aforementioned substituent Ra.

The charge transporting polymer may have a terminal group P containing an oxetanyl group. The terminal group P may contain any group other than the oxetanyl group. Examples of the terminal group P include "oxetanyl group" and "aromatic ring group substituted with a group containing an oxetanyl group".

The "aromatic ring group" is, for example, an aromatic ring group having 2 to 30 carbon atoms. Examples of aromatic rings include aromatic hydrocarbons and aromatic heterocyclic compounds. Examples of aromatic rings include monocycles, fused polycyclic aromatic hydrocarbons, and fused polycyclic aromatic heterocycles. Aromatic hydrocarbons are as described above. Aromatic heterocyclic compounds include, for example, pyridine, pyrazine, quinoline, isoquinoline, acridine, phenanthroline, furan, pyrrole, thiophene, carbazole, oxazole, oxadiazole, thiadiazole, triazole, benzoxazole, benzoxadiazole, benzothiadiazole, It contains at least one selected from the group consisting of benzotriazole and benzothiophene. The aromatic ring may be a structure in which two or more selected from independent single rings or condensed rings are bonded. Examples of the structure include biphenyl, terphenyl, triphenylbenzene, bithiophene, and the like. The aromatic ring group may have a substituent, and an example of the substituent is the substituent Ra.

The aromatic ring is preferably an aromatic hydrocarbon, more preferably benzene, from the viewpoint of commercial availability of a monomer for introducing the terminal group P and ease of synthesis.

An example of the terminal group P is a terminal group represented by the following formula (P).

In the formula, Ar represents a substituted or unsubstituted aromatic ring group, and PGG represents a group containing an oxetanyl group. a represents 0 or 1, and z represents an integer of 1 or more.

The upper limit of z is determined by the structure of Ar. For example, when Ar is a benzene ring, z is 5 or less, and may be 2 or less.

An example of the terminal group P is a terminal group represented by the following formula (P1). The terminal group represented by formula (P1) is a preferable group from the viewpoint of obtaining good heat resistance.

In the formula, Ar represents a substituted or unsubstituted aromatic ring group, L represents a linking group, and PG represents a substituted or unsubstituted oxetanyl group. a and x each independently represent 0 or 1, and y represents an integer of 1 or more.

An example of the terminal group represented by formula (P1) is a terminal group represented by formula (P2) below. The terminal group represented by formula (P2) is a preferable group from the viewpoint of obtaining good heat resistance.

In the formula, Ar represents a substituted or unsubstituted aromatic ring group having 2 to 30 carbon atoms, X represents a divalent group represented by any of the following formulas (X1) to (X10), and Y represents an alkylene group having 1 to 10 carbon atoms, and PG represents a substituted or unsubstituted oxetanyl group. a to c each independently represent 0 or 1, and d represents 1 or 2. However, when d is 2, a is 1.

In the formula, R each independently represents a hydrogen atom, a linear, cyclic or branched alkyl group having 1 to 22 carbon atoms, or an aryl group or heteroaryl group having 2 to 30 carbon atoms.

The charge transporting polymer may be linear or may have a branched structure. The charge-transporting polymer includes, for example, at least a divalent structural unit L having charge-transporting properties and a monovalent structural unit T, and may further include a trivalent or higher-valent structural unit B contained in the branch portion. The charge-transporting polymer has charge-transporting properties, for example, and includes at least a trivalent or higher-valent structural unit B and a monovalent structural unit T included in the branch portion, and may further include a divalent structural unit. The molecular chain has a chain structure containing at least one type selected from the group consisting of divalent structural units and trivalent structural units. Branched charge-transporting polymers have excellent heat resistance and also exhibit good solubility and curability because many terminal groups can be introduced. The charge transporting polymer may contain only one type of each structural unit, or may contain multiple types of each structural unit. In the charge transporting polymer, each structural unit is bonded to each other at one to three or more bonding sites.

The charge transporting polymer has a structural unit including at least one structure selected from the group consisting of an aromatic amine structure, a carbazole structure, a thiophene structure, a benzene structure, a pyrrole structure, a furan structure, and a fluorene structure. Contained in unit L, structural unit B, or both structural unit L and structural unit B.

In some embodiments, the charge transporting polymer includes a branched structure having at least one structural unit B and three or more structural units L bonded to the one structural unit B. For example, the charge transporting polymer has one structural unit B and three or more structural units L bonded to the one structural unit B, and further, for each of the three or more structural units L, It includes a multi-branched structure having at least one other structural unit B bonded to the structural unit L and two or more other structural units L bonded to the another structural unit B.

Examples of multi-branched structures contained in charge transporting polymers include the following. In the structure, "L" represents a divalent structural unit, "B" represents a trivalent or higher valence structural unit, and "T" represents a monovalent structural unit. In the following structures, a plurality of L's may be the same structural unit or different structural units. The plurality of B's may be the same structural unit or different structural units. The plurality of T's may be the same structural unit or different structural units. Note that the charge transporting polymer is not limited to a polymer having the following structure.

(structural unit L)
The structural unit L is a divalent structural unit having charge transport properties. The structural unit L is not particularly limited as long as it contains an atomic group having the ability to transport 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. Structure, dihydrophenanthrene structure, pyridine structure, pyrazine structure, quinoline structure, isoquinoline structure, quinoxaline structure, acridine structure, diazaphenanthrene structure, furan structure, pyrrole structure, oxazole structure, oxadiazole structure, thiazole structure, thiadiazole structure, triazole structure, a benzothiophene structure, a benzoxazole structure, a benzoxadiazole structure, a benzothiazole structure, a benzothiadiazole structure, a benzotriazole structure, an N-arylphenoxazine structure, and a structure containing one or more of these. be done. The aromatic amine structure is preferably a triarylamine structure, more preferably a triphenylamine structure.

In some embodiments, the structural unit L is a substituted or unsubstituted aromatic amine structure, a carbazole structure, a thiophene structure, a benzene structure, a pyrrole structure, a furan structure, and It preferably contains one or more structures selected from the group consisting of fluorene structures, and is selected from the group consisting of substituted or unsubstituted aromatic amine structures, carbazole structures, thiophene structures, furan structures, and fluorene structures. It is more preferable to include one or more types of structures, and more preferably to include one or more types of structures selected from the group consisting of a substituted or unsubstituted aromatic amine structure and a carbazole structure. In another embodiment, the structural unit L is substituted or unsubstituted one selected from the group consisting of a fluorene structure, a benzene structure, a phenanthrene structure, a pyridine structure, and a quinoline structure, from the viewpoint of obtaining excellent electron transport properties. It is preferable that more than one type of structure is included.

(Structural unit B)
Structural unit B is a trivalent or higher-valent structural unit contained in a branch when the charge transporting polymer has a branched structure. From the viewpoint of improving the durability of the organic electronics element, the structural unit B has a valence of, for example, hexavalence or less, and is preferably trivalent or tetravalent. Structural unit B may be a unit having charge transport properties. For example, from the viewpoint of improving the durability of organic electronic devices, the structural unit B may be a substituted or unsubstituted aromatic amine structure, a carbazole structure, a fused polycyclic aromatic hydrocarbon structure, or one or two of these. selected from structures containing more than one species. For example, the structural unit B is selected from substituted or unsubstituted aromatic amine structures, carbazole structures, fused polycyclic aromatic hydrocarbon structures, and structures containing one or more of these.

(Structural unit T)
The structural unit T is a monovalent structural unit contained in the terminal portion of the charge transporting polymer, and is a structural unit containing a terminal group. The structural unit T may include at least a structural unit TP including a terminal group P and an arbitrary structural unit TO different from the structural unit TP. The structural unit TO does not contain a terminal group P.

The structural unit TP is a structural unit containing a terminal group P. The terminal group P explained above may be a structural unit TP, and an example of the structural unit TP is a group represented by formula (P1).

The structural unit TO is not particularly limited, and is selected from, for example, substituted or unsubstituted aromatic hydrocarbon structures, aromatic heterocyclic structures, and structures containing one or more of these. In one embodiment, the structural unit TO 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 aromatic hydrocarbon structure, and a substituted or unsubstituted benzene structure. More preferably, it has a structure. The structural unit TO may have the same structure as the structural unit L except for the valence. 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 preferably has a substituted or unsubstituted benzene structure. More preferably, it has a structure.

A specific example of the structural unit TO is a structural unit represented by the following formula (3). The structural unit TO is not limited to the following.

Each R independently represents a hydrogen atom or a substituent. For example, each R is independently selected from the group consisting of -R ¹ , -OR ² , -SR ³ , -OCOR ⁴ , -COOR ⁵ , -SiR ⁶ R ⁷ R ⁸ , and a halogen group. R ¹ to R ⁸ are as described for structural unit (1).

The structural unit TO includes, for example, at least one structural unit selected from the group consisting of a structural unit represented by the following formula (3-1) and a structural unit represented by (3-2).

In the formula, n and m each independently represent an integer of 1 to 4. n and m may be the same or different, preferably the same.

In the formula, n represents an integer from 4 to 20. n is, for example, 4 to 16, preferably 4 to 12.

In the charge transporting polymer, it is preferable that the oxetanyl group is introduced at least into the terminal portion (ie, the structural unit T) of the charge transporting polymer. The oxetanyl group may be introduced into a portion other than the terminal (namely, the structural unit L or B), or may be introduced into both the terminal and the portion other than the terminal. From the viewpoint of achieving both curability and charge transportability, it is preferable that it is introduced only at the end portion. When the charge transporting polymer has a branched structure, the oxetanyl group may be introduced into the main chain of the charge transporting polymer, into the side chain, or into both the main chain and the side chain. You can.

The charge transporting polymer may have a polymerizable functional group other than the oxetanyl group. For example, the number of polymerizable functional groups per molecule of the charge transporting polymer may be 2 or more, 3 or more, 5 or more, 10 or more, or 20 or more from the viewpoint of obtaining a sufficient change in solubility. . The number of polymerizable functional groups may be 1,000 or less, 800 or less, 700 or less, 600 or less, or 500 or less from the viewpoint of maintaining charge transport properties.

When the charge transporting polymer has an oxetanyl group at the terminal, from the viewpoint of obtaining good curability, the ratio of the structural unit TP is, for example, 5 mol% or more, 10 mol% or more, based on the total of the terminal structural units. , 20 mol% or more, 30 mol% or more, or 40 mol% or more. From the viewpoint of obtaining good charge transport properties, the ratio of the structural units TP is, for example, 85 mol% or less, 80 mol% or less, 75 mol% or less, 65 mol% or less, based on the total of the terminal structural units. Or it may be 60 mol% or less.

The content and ratio of the polymerizable functional group per molecule of the charge transporting polymer are determined by the amount of the polymerizable functional group used to synthesize the charge transporting polymer (for example, the amount of the monomer having the polymerizable functional group). It can be determined as an average value using the amount x number of polymerizable functional groups per monomer), the amount of monomers corresponding to each structural unit charged, the mass average molecular weight of the charge transporting polymer, etc. The content of the polymerizable functional group is determined by the ratio of the integral value of the signal derived from the polymerizable functional group in the ¹ H NMR (nuclear magnetic resonance) spectrum of the charge transporting polymer to the integral value of the entire spectrum, It can be calculated as an average value using mass average molecular weight, etc. Because it is simple, if the amount of preparation is clear, a value determined using the amount of preparation is preferably used.

(number average molecular weight)
In the case of a linear charge-transporting polymer, the number average molecular weight of the charge-transporting polymer can be adjusted as appropriate in consideration of solubility in a solvent, film-forming properties, and the like. The number average molecular weight may be, for example, 500 or more, 1,000 or more, 2,000 or more, or 3,000 or more from the viewpoint of excellent charge transport properties. The number average molecular weight is, for example, 200,000 or less, 100,000 or less, 50,000 or less, or 20,000 or less, from the viewpoint of maintaining good solubility in the solvent and facilitating the preparation of the ink composition. It may be.

In the case of a branched charge-transporting polymer, the number average molecular weight of the charge-transporting polymer can be appropriately adjusted in consideration of solubility in a solvent, film-forming properties, and the like. The number average molecular weight may be, for example, 500 or more, 1,000 or more, 2,000 or more, or 5,000 or more from the viewpoint of excellent charge transport properties. The number average molecular weight is, for example, 1,000,000 or less, 100,000 or less, 50,000 or less, or 30,000 or less, from the viewpoint of maintaining good solubility in the solvent and facilitating the preparation of the ink composition. It may be less than 000.

(mass average molecular weight)
In the case of a linear charge-transporting polymer, the mass average molecular weight of the charge-transporting polymer can be adjusted as appropriate in consideration of solubility in a solvent, film-forming properties, and the like. The mass average molecular weight may be, for example, 1,000 or more, 3,000 or more, 5,000 or more, or 10,000 or more from the viewpoint of excellent charge transport properties. The weight average molecular weight is, for example, 500,000 or less, 300,000 or less, 150,000 or less, 100,000 or less, from the viewpoint of maintaining good solubility in the solvent and facilitating the preparation of the ink composition. or 50,000 or less.

In the case of a branched charge-transporting polymer, the weight average molecular weight of the charge-transporting polymer can be adjusted as appropriate in consideration of solubility in a solvent, film-forming properties, and the like. The mass average molecular weight may be, for example, 1,000 or more, 5,000 or more, 10,000 or more, or 30,000 or more from the viewpoint of excellent charge transport properties. The weight average molecular weight is, for example, 1,000,000 or less, 700,000 or less, 400,000 or less, 200,000 or less, from the viewpoint of maintaining good solubility in the solvent and facilitating the preparation of the ink composition. or less than or equal to 100,000.

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

(ratio of structural units)
When the charge-transporting polymer contains a structural unit L, the ratio of the structural unit L is, for example, 10 mol% or more, 20 mol% or more, or 30 mol% or more, based on all structural units, from the viewpoint of obtaining sufficient charge-transporting properties. It may be mol% or more. The ratio of the structural unit L may be, for example, 97 mol% or less, 92 mol% or less, or 85 mol% or less, taking into account the structural unit T and the structural unit B introduced as necessary.

From the viewpoint of solubility and curability, the proportion of structural units T contained in the charge transporting polymer is, for example, 3 mol% or more, 8 mol% or more, or 15 mol% or more, based on the total structural units. good. The above range is also a preferable range from the viewpoint of improving the characteristics of organic electronic devices, or from the viewpoint of suppressing the increase in viscosity and favorably synthesizing the charge transporting polymer. The ratio of the structural units T may be, for example, 60 mol% or less, 55 mol% or less, or 50 mol% or less, from the viewpoint of obtaining sufficient charge transport properties.

When the charge transporting polymer contains structural unit B, the ratio of structural unit B is, for example, 1 mol% or more, 5 mol% or more, based on all structural units, from the viewpoint of improving the durability of organic electronic devices. It may be 10 mol% or more. The ratio of the structural unit B is, for example, 50 mol% or less, 40 mol% or less, from the viewpoint of suppressing the increase in viscosity and favorably synthesizing the charge-transporting polymer, or obtaining sufficient charge-transporting property. It may be 30 mol% or less.

Considering the balance of charge transportability, durability, productivity, etc., the ratio (molar ratio) of the structural unit L and the structural unit T is, for example, L:T=100:1 to 70, 100:3 to 50, or The ratio may be 100:5 to 30. When the charge transporting polymer contains structural unit B, the ratio (molar ratio) of structural unit L, structural unit T, and structural unit B is, for example, L:T:B=100:10 to 200:10 to 100, It may be 100:20-180:20-90, or 100:40-160:30-80.

The ratio of structural units can be determined using the charged amount of the monomer corresponding to each structural unit used to synthesize the charge transporting polymer. The ratio of structural units can be calculated as an average value using the integral value of the spectrum derived from each structural unit in the ¹ H NMR spectrum of the charge transporting polymer. Because it is simple, if the amount of preparation is clear, a value determined using the amount of preparation is preferably used. The ratio regarding the above-mentioned terminal groups can also be determined by a method using the amount charged or a ¹ H NMR spectrum.

The degree of polymerization (number of structural units) of the charge transporting polymer may be, for example, 5 or more, 10 or more, or 20 or more from the viewpoint of stabilizing the film quality of the coating film. The degree of polymerization may be, for example, 1,000 or less, 700 or less, or 500 or less from the viewpoint of solubility in a solvent.

The degree of polymerization can be determined as an average value using the mass average molecular weight of the charge transporting polymer, the molecular weight of the structural unit, and the ratio of the structural units.

(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, Sonogashira coupling, Stille coupling, and Buchwald-Hartwig coupling can be used. Suzuki coupling causes a cross-coupling reaction between an aromatic boronic acid derivative and an aromatic halide using a Pd catalyst. According to Suzuki coupling, a charge transporting polymer can be easily produced by bonding desired aromatic rings to each other.

In the coupling reaction, for example, a Pd(0) compound, a Pd(II) compound, a Ni compound, etc. are used as a catalyst. It is also possible to use a catalyst species generated by mixing tris(dibenzylideneacetone)dipalladium(0), palladium(II) acetate, or the like as a precursor with a phosphine ligand. For the method of synthesizing the charge transporting polymer, for example, the description in International Publication No. 2010/140553 can be referred to.

[Optional ingredients]
The organic electronic material may further contain arbitrary components other than the ionic compound and the charge transporting polymer, such as a dopant, a polymerization initiator, an ionic compound, a charge transporting polymer, and an additive. Examples of additives include polymerization inhibitors, stabilizers, thickeners, gelling agents, flame retardants, antioxidants, reduction inhibitors, oxidizing agents, reducing agents, surface modifiers, emulsifiers, antifoaming agents, Examples include dispersants and surfactants.

[Content]
The content of the ionic compound may be, for example, 1% by mass or more, 10% by mass or more, or 20% by mass or more based on the charge transporting polymer, from the viewpoint of improving the curability of the organic electronic material. From the viewpoint of maintaining good film formability, the amount may be, for example, 10% by mass or less, 5% by mass or less, or 3% by mass or less with respect to the charge transporting polymer.

The content of the charge transporting polymer may be, for example, 50% by mass or more, 70% by mass or more, or 80% by mass or more with respect to the mass of the organic electronics material from the viewpoint of obtaining good charge transportability. The total content of the charge transporting polymer and the ionic compound can also be 100% by mass based on the mass of the organic electronics material.

<Ink composition>
The ink composition contains the organic electronic material and a solvent capable of dissolving or dispersing the material. By using the ink composition, an 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 organic solvents 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, tetralin, phenylcyclohexane, and diphenylmethane. ; Aliphatic ethers such as ethylene glycol dimethyl ether, ethylene glycol diethyl ether, propylene glycol-1-monomethyl ether acetate; 1,2-dimethoxybenzene, 1,3-dimethoxybenzene, anisole, phenethole, 2-methoxytoluene, 3- Aromatic ethers such as methoxytoluene, 4-methoxytoluene, 2,3-dimethylanisole, 2,4-dimethylanisole, 3-phenoxytoluene; fats such as ethyl acetate, n-butyl acetate, ethyl lactate, n-butyl lactate, etc. Aromatic esters such as phenyl acetate, phenyl propionate, methyl benzoate, ethyl benzoate, propyl benzoate, n-butyl benzoate; Amides such as N,N-dimethylformamide and N,N-dimethylacetamide Solvents include dimethyl sulfoxide, tetrahydrofuran, acetone, chloroform, methylene chloride, and the like. Preferably, aromatic hydrocarbons, aliphatic esters, aromatic esters, aliphatic ethers, and aromatic ethers, more preferably aromatic hydrocarbons, aromatic ethers, and aromatic esters, still more preferably , aromatic hydrocarbons.

[Additive]
The ink composition may further contain additives as optional components. Examples of additives include polymerization inhibitors, stabilizers, thickeners, gelling agents, flame retardants, antioxidants, reduction inhibitors, oxidizing agents, reducing agents, surface modifiers, emulsifiers, antifoaming agents, Examples include dispersants and surfactants.

[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 such that the content of the charge transporting polymer is, for example, 0.1% by mass or more, 0.2% by mass or more, or 0.5% by mass or more. The amount may be The content of the solvent may be such that the content of the charge transporting polymer relative to the solvent is, for example, 20% by mass or less, 15% by mass or less, or 10% by mass or less.

<Organic layer>
The organic layer is a layer formed using the organic electronic material or the ink composition, and includes a cured product of the charge transporting polymer. By using the ink composition, an organic layer can be formed satisfactorily by a coating method. Application methods include, for example, spin coating methods; casting methods; dipping methods; plate printing methods such as letterpress printing, intaglio printing, offset printing, planographic printing, letterpress reversal offset printing, screen printing, and gravure printing; inkjet methods, etc. Known methods such as plateless printing can be used. When forming an organic layer by a coating method, the uncured coating film obtained after coating may be dried using a hot plate or an oven to remove the solvent.

By applying treatments such as light irradiation and heat treatment to the coating film, it is possible to advance the polymerization reaction of the charge transporting polymer and change the solubility of the coating film. By laminating another layer on the cured organic layer (cured film) obtained after the change, it becomes possible to easily create a multilayer organic electronic device. For the method of forming the organic layer, for example, the description in International Publication No. 2010/140553 can be referred to. The heat treatment of the coating film can be performed in an air atmosphere or a nitrogen atmosphere. From the viewpoint of improving charge transport properties, it is preferable to heat-treat the coating film in a nitrogen atmosphere. The ionic compound can particularly improve the solvent resistance of the organic layer when the coating film is heat-treated in a nitrogen atmosphere.

The thickness of the organic layer after curing is, for example, 0.1 nm or more, 1 nm or more, or 3 nm or more from the viewpoint of improving charge transport efficiency. The thickness of the organic layer is, for example, 300 nm or less, 200 nm or less, or 100 nm or less from the viewpoint of reducing electrical resistance.

<Organic electronics device>
The organic electronic device has at least the organic layer. Examples of the organic electronics device include organic EL devices such as organic light emitting diodes (OLEDs), organic photoelectric conversion devices, and organic transistors. The organic electronic device preferably has a structure in which an organic layer is disposed between at least one pair of electrodes.

[Organic EL element]
The organic EL element has at least the organic layer. An organic EL device usually includes a light emitting layer, an anode, a cathode, and a substrate, and optionally includes functional layers such as a hole injection layer, an electron injection layer, a hole transport layer, and an electron transport layer. There is. Each layer may be formed by a vapor deposition method or a coating method. Known materials can be used to form each layer. Regarding known materials, for example, the description in International Publication No. 2010/140553 can be referred to. The organic EL device preferably has an organic layer as a light emitting layer or a functional layer, more preferably as a functional layer, and still more preferably as at least one of a hole injection layer and a hole transport layer. For the structure and manufacturing method of organic EL, for example, the description in International Publication No. 2010/140553 can be referred to.

The organic layer formed using the organic electronics material is preferably used as at least one of a hole injection layer and a hole transport layer, and more preferably used at least as a hole injection layer. As mentioned above, these layers can be easily formed by using an ink composition containing an organic electronics material.

When the organic EL element has an organic layer formed using the above organic electronics material as a hole transport layer and further has a hole injection layer, a known material can be used for the hole injection layer. When the organic EL element has an organic layer formed using the above organic electronics material as a hole injection layer and further has a hole transport layer, a known material can be used for the hole transport layer. It is also preferred to use organic electronic materials for both the hole injection layer and the hole transport layer.

<Display element, lighting device, display device>
The display element includes the organic EL element. For example, a color display element can be obtained by using organic EL elements as elements corresponding to red, green, and blue (RGB) pixels. Image forming methods include a simple matrix type in which individual organic EL elements arranged in 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.

The lighting device includes the organic EL element. The display device includes an illumination device and a liquid crystal element as a display means. For example, the display device may be a display device using the lighting device as a backlight and a known liquid crystal element as a display means, that is, a liquid crystal display device.

Embodiments of the present invention will be specifically described using examples. Embodiments of the present invention are not limited to the following examples.

<Synthesis of ionic compounds>
(Synthesis of ionic compound 1)
75 g of acetone and 15 g of pure water were added to 5.497 g (30 mmol) of N,N-diphenylmethylamine and stirred to obtain a liquid containing N,N-diphenylmethylamine. 11.0 g of a 10% by mass aqueous hydrogen chloride solution was slowly added dropwise to the obtained liquid, and after the dropwise addition was completed, the mixture was stirred for 1 hour. The solvent was distilled off under reduced pressure from the stirred liquid. Next, 231.7 g (33 mmol) of sodium tetrakis(pentafluorophenyl)borate (10% by mass aqueous solution) was mixed and stirred for 1 hour. The precipitate was washed with water five times and dried to obtain ionic compound 1. The chemical structure of ionic compound 1 is shown in the following formula.

(Synthesis of ionic compound 2)
75 g of acetone and 15 g of pure water were added to 8.927 g (30 mmol) of N,N-dimethyloctadecylamine and stirred to obtain a liquid containing N,N-dimethyloctadecylamine. 11.0 g of a 10% by mass aqueous hydrogen chloride solution was slowly added dropwise to the obtained liquid, and after the dropwise addition was completed, the mixture was stirred for 1 hour. The solvent was distilled off under reduced pressure from the stirred liquid. Next, 231.7 g (33 mmol) of sodium tetrakis(pentafluorophenyl)borate (10% by mass aqueous solution) was mixed and stirred for 1 hour. The precipitate was washed with water five times and dried to obtain ionic compound 2. The structural formula of ionic compound 2 is shown below.

<Synthesis of charge transporting polymer>
(Preparation of Pd catalyst)
In a glove box under a nitrogen atmosphere, 73.2 mg (80 μmol) of tris(dibenzylideneacetone)dipalladium was weighed into a glass sample tube at room temperature, 15 mL of toluene was added, and the mixture was stirred for 30 minutes. In a glove box under a nitrogen atmosphere, 129.6 mg (640 μmol) of tris(t-butyl)phosphine was weighed into a glass sample tube, 5 mL of toluene was added, and the mixture was stirred for 5 minutes. These liquids were mixed and stirred at 80° C. for 2 hours, and insoluble matter was removed from the resulting liquid using a membrane filter with a pore size of 0.2 μm, and the liquid was used as a catalyst. All solvents were used after degassing with nitrogen bubbles for over 30 minutes.

(Synthesis of charge transporting polymer 1)
In a 200 mL three-neck round bottom flask (made of glass), add 5.15 g (10.0 mmol) of the following monomer 1, 1.93 g (4.0 mmol) of the following monomer 2, and 1.08 g (4.0 mmol) of the following monomer 3. , 1.17 g (4.0 mmol) of the following monomer 4 and 90 mL of toluene were added, and 7.8 mL of a 1% by mass tetraethylammonium hydroxide aqueous solution and 14.2 mL of a 3M potassium hydroxide aqueous solution were added. All solvents were used after degassing with nitrogen bubbles for at least 30 minutes. A reflux condenser tube and a nitrogen gas flow tube were attached to the flask containing the reaction solution, and the flask was immersed in an oil bath heated to 60° C. and stirred for 30 minutes. Subsequently, 2.0 mL of the Pd catalyst liquid prepared above was added, and the temperature of the oil bath was raised to 120° C. to conduct a reaction. The reaction solution was heated to reflux for 2 hours. The operations up to this point were performed under a nitrogen stream.

After the reaction was completed, the organic layer was washed with water and poured into a methanol-water (9:1) mixture. The resulting precipitate was suction filtered and washed with a methanol-water (9:1) mixture. The obtained precipitate was washed with ethyl acetate, and the eluted solid was vacuum dried. The dried solid was dissolved in toluene, a metal adsorbent ("Triphenylphosphine, polymer-bound on styrene-divinylbenzene copolymer" manufactured by Strem Chemicals, 200 mg per 100 mg of precipitate) was added, and the mixture was stirred overnight. After the stirring was completed, the metal adsorbent and insoluble matter were removed by filtration, and the resulting liquid was poured into methanol. The precipitate was suction-filtered, the obtained precipitate was washed with methanol, and the solid was vacuum-dried to obtain charge transporting polymer 1. Charge transporting polymer 1 had a number average molecular weight of 18,000 and a mass average molecular weight of 55,000. In charge transporting polymer 1, the thermal mass decrease when heated at 300° C. was 5% by mass or less relative to the mass before heating.

(Measurement of number average molecular weight and mass average molecular weight)
The number average molecular weight and mass average molecular weight were measured by GPC. The calibration curve was approximated using standard polystyrene samples. The measurement conditions are as follows.
Equipment: High performance liquid chromatograph Prominence Shimadzu Corporation
Liquid pump (LC-20AD)
Deaeration unit (DGU-20A)
Auto sampler (SIL-20AHT)
Column oven (CTO-20A)
PDA detector (SPD-M20A)
Differential refractive index detector (RID-20A)
Column: Gelpack (registered trademark) Showa Denko Materials Techno Service Co., Ltd.
GL-A160S (serial number: 686-1J27)
GL-A150S (serial number: 685-1J27)
Eluent: Tetrahydrofuran (THF) (for HPLC, contains stabilizer) Fujifilm Wako Pure Chemical Industries, Ltd. Sample concentration: 20 mg of polymer/18 mL of THF
Injection volume: 20μL
Flow rate: 1mL/min
Column temperature: 40℃
Detection wavelength: 254nm
Molecular weight standard material: PStQuick A/B/C Tosoh Corporation

[Example 1]
[Solvent resistance evaluation]
An organic layer was formed using an organic electronics material, and the solvent resistance (that is, the curability of the charge transporting polymer) was evaluated by measuring the residual film rate. The results are shown in Table 1.

(Formation of organic layer)
Ionic Compound 1 (10 mg) was weighed into a 20 mL screw tube, and chlorobenzene (5 mL) was added and stirred to obtain a polymerization initiator solution. Next, charge transport polymer 1 (10 mg) and chlorobenzene (738 μL) were added to a 9 mL screw tube to dissolve the charge transport polymer. Thereafter, 155 μL of the polymerization initiator solution was added to the 9 mL screw tube and stirred to prepare an ink composition. The ink composition was dropped onto a quartz substrate (22 mm long x 29 mm wide x 0.7 mm thick) in the atmosphere, and a coating film was formed using a spin coater (rotation speed 3,000 min ^-1 ). Subsequently, curing was performed by heating in a nitrogen atmosphere for 30 minutes under each temperature condition to form an organic layer with a thickness of 40 nm on the quartz substrate.

(Measurement of residual film rate)
The absorbance A of the organic layer formed on the quartz substrate was measured using a spectrophotometer ("UV-2700" manufactured by Shimadzu Corporation). Subsequently, the sample was immersed in toluene (10 mL, 25°C) in an environment of 25°C so that the organic layer after measurement was on the top, and left to stand for 10 minutes. The absorbance B of the organic layer after immersion in toluene was measured, and the residual film rate was calculated from the absorbance A of the formed organic layer and the absorbance B of the organic layer after immersion in toluene using the following formula. Note that the value at the maximum absorption wavelength of the organic layer was used as the absorbance value. The higher the residual film ratio, the better the solvent resistance.

[Example 2]
[Charge transport evaluation]
A HOD (hole-only device) was fabricated using an organic electronics material, and its conductivity and heat resistance were evaluated. The results are shown in Table 2.

(Preparation of HOD)
Ionic Compound 1 (10 mg) was weighed into a 20 mL screw tube, and chlorobenzene (5 mL) was added and stirred to obtain a polymerization initiator solution. Next, charge transport polymer 1 (30 mg) and chlorobenzene (723 μL) were added to a 9 mL screw tube to dissolve the charge transport polymer. Thereafter, 152 μL of the polymerization initiator solution was added to the 9 mL screw tube and stirred to prepare an ink composition. After filtering the ink composition through a polytetrafluoroethylene (PTFE) filter (pore size 0.2 μm), it was dropped onto a glass substrate (length 22 mm x width 29 mm x thickness 0.7 mm) patterned with ITO to a width of 1.6 mm. Then, a coating film was formed using a spin coater. Subsequently, heat curing was performed in a nitrogen atmosphere at the temperature shown in Table 2 for 30 minutes to form an organic layer with a thickness of 100 nm on the quartz substrate. The glass substrate was transferred to a vacuum evaporator, and a film of Al (100 nm) was formed on the organic layer by a evaporation method, and a sealing treatment was performed to produce an HOD.

A voltage was applied to the HOD, and the voltage at a current density of 300 mA/cm ² was measured. The smaller the voltage value, the better the hole injection function.

[Comparative Examples 1 and 2]
Solvent resistance and charge transport properties were evaluated in the same manner as in Example 1, except that Ionic Compound 1 was changed to Ionic Compound 2. The results are shown in Tables 1 and 2.

Claims (15)

An organic electronics material containing an ionic compound containing diphenylmethylammonium and a charge transporting polymer having an oxetanyl group. The organic electronic material according to claim 1, wherein the ionic compound comprises a substituted or unsubstituted tetrakis(aryl)boron anion. 2. The organic electronic material of claim 1, wherein the ionic compound comprises diphenylmethylammonium tetrakis(pentafluorophenyl)borate. The charge transporting polymer has a structural unit containing at least one structure selected from the group consisting of an aromatic amine structure, a carbazole structure, a thiophene structure, a benzene structure, a pyrrole structure, a furan structure, and a fluorene structure. Item 1. Organic electronics material according to item 1. The organic electronic material according to claim 1, wherein the charge transporting polymer has a structural unit containing an aromatic amine structure. The organic electronic material according to claim 1, wherein the charge transporting polymer has a structural unit containing an aromatic amine structure substituted with a fluoro group. The organic electronic material of claim 1, wherein the charge transporting polymer comprises a branched polymer. An ink composition comprising the organic electronic material according to claim 1 and a solvent. An organic layer formed using the ink composition described in the organic electronic material according to claim 1. An organic electronic device comprising the organic layer according to claim 9. An organic electroluminescent device comprising the organic layer according to claim 9. A display element comprising the organic electroluminescent element according to claim 11. A lighting device comprising the organic electroluminescent element according to claim 11. A display device comprising the organic electroluminescent element according to claim 11. A display device comprising the lighting device according to claim 13 and a liquid crystal element as display means.