JP7363784B2 - Charge-transporting polymers and organic electronic devices - Google Patents

Description

The present disclosure relates to charge transporting polymers, charge transporting materials, ink compositions, organic layers, organic electronic devices, organic electroluminescent devices, display devices, lighting devices, and display devices.

Organic electronic devices are devices that operate electrically using organic materials, and are expected to exhibit features such as energy saving, low cost, and flexibility, and are attracting attention as a technology that can replace conventional silicon-based inorganic semiconductors. has been done.

Examples of organic electronic devices include organic electroluminescent devices (organic EL devices), organic photoelectric conversion devices, and organic transistors.

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

Organic EL devices are broadly classified into two types, low-molecular type organic EL devices and high-molecular type organic EL devices, based on the organic materials used. In a polymer type organic EL element, a polymer material is used as an organic material, and in a low molecule type organic EL element, a low molecule material is used.

Compared to low-molecular-weight organic EL devices, which are mainly formed in a vacuum system, polymer-type organic EL devices can be easily formed using wet processes such as inkjet printing, so they are expected to be used in large-screen organic EL devices in the future. It is expected to be an essential element for displays. For this reason, the development of materials suitable for wet processes is progressing (see, for example, Patent Document 1).

International Publication No. 2010/140553

In general, organic EL elements manufactured by a wet process using polymeric materials have the advantage of being easy to reduce cost and increase in area. However, conventional polymer materials are desired to be further improved in wet process properties such as solubility in solvents and curability. Further, organic layers formed using polymeric materials are required to have further improvements in properties such as electrical conductivity and thermal stability.

In view of the above, the present disclosure provides a charge transporting polymer, a charge transporting material, and an ink composition that are suitable for wet processing and can form an organic layer with excellent conductivity and thermal stability. The present disclosure also provides an organic layer with excellent solvent resistance, conductivity, and thermal stability, and an organic electronic device, an organic EL device, a display device, a lighting device, and a display device including the organic layer. .

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

One embodiment includes a terminal group P containing an aromatic ring group substituted with a group PG containing a cationically polymerizable functional group and an alkylene group having 4 to 30 carbon atoms, and a substituent SG that does not contain a cationically polymerizable functional group. The present invention relates to a charge transporting polymer having a terminal group S containing a substituted aromatic ring group, and containing 25 to 95 mol% of the terminal group P based on all terminal groups.

In one embodiment, in the charge transporting polymer, the group PG includes a group containing an oxetanyl group and an alkylene group having 4 to 30 carbon atoms.

In one embodiment, in any of the above charge transporting polymers, the terminal group S is substituted with a terminal group R containing an aromatic ring group substituted with a linear alkyl group, and a branched or cyclic substituent. The terminal group B contains at least one type selected from the group consisting of terminal groups B containing an aromatic hydrocarbon group.

In one embodiment, any of the charge transporting polymers is one type selected from the group consisting of a substituted or unsubstituted aromatic amine structure, a carbazole structure, a thiophene structure, a bithiophene structure, a benzene structure, and a fluorene structure. Contains the above structure.

In one embodiment, any of the charge transporting polymers has a structure branched in three or more directions.

Another embodiment relates to a charge transporting material containing any of the charge transporting polymers described above.

In one embodiment, the charge transporting material further contains a cationic polymerization initiator.

Another embodiment relates to an ink composition containing any of the charge transporting polymers or charge transporting materials described above and a solvent.

Another embodiment relates to an organic layer formed using any of the charge-transporting polymers, any of the charge-transporting materials, or the ink compositions.

Another embodiment relates to an organic electronic device having the organic layer.

Another embodiment relates to an organic electroluminescent device having the organic layer.

Further, another embodiment includes: a display element including the organic electroluminescent element; a lighting device including the organic electroluminescent element; and the lighting device and a liquid crystal element as a display means. , relates to a display device.

According to the present disclosure, there are provided a charge transporting polymer, a charge transporting material, and an ink composition that are suitable for wet processes and can form an organic layer with excellent conductivity and thermal stability. Further, according to the present disclosure, an organic layer having excellent solvent resistance, conductivity, and thermal stability, and an organic electronic device, an organic EL device, a display device, a lighting device, and a display device including the organic layer are provided. provided.

FIG. 2 is a schematic cross-sectional view showing a device for evaluation used in Examples.

Embodiments of the present invention will be described below. The invention is not limited to these embodiments.

<Charge transporting polymer>
According to one embodiment, the charge transporting polymer has a terminal group P that includes an aromatic ring group substituted with a group PG that includes a cationically polymerizable functional group and an alkylene group having 4 to 30 carbon atoms, and a cationically polymerizable functional group. and a terminal group S containing an aromatic ring group substituted with a substituent SG containing no group. The charge transporting polymer contains 25 to 95 mol% of terminal groups P, based on all terminal groups.

Charge transporting polymers are polymers that have the ability to transport charge. In the present disclosure, the term "polymer" also includes so-called "oligomers" having a small number of structural units.

By introducing the terminal group P and the terminal group S into the charge transporting polymer in a specific ratio, it is possible to improve the solubility of the charge transporting polymer in a solvent in a wet process, and to achieve excellent curing. You can get sex. Furthermore, by using a charge transporting polymer in which terminal groups P and S are introduced in a specific ratio, an organic layer exhibiting excellent solvent resistance, conductivity, and thermal stability can be obtained.

[Terminal group P]
The charge transporting polymer has a terminal group P at the end of its molecular chain. The terminal group P includes an aromatic ring group substituted with a group PG containing a cationically polymerizable functional group and an alkylene group having 4 to 30 carbon atoms. The group PG containing a cationically polymerizable functional group and an alkylene group having 4 to 30 carbon atoms may contain any group other than the cationically polymerizable functional group and the alkylene group having 4 to 30 carbon atoms.

(Group PG containing a cationically polymerizable functional group and an alkylene group having 4 to 30 carbon atoms)
A cationic polymerizable functional group is a functional group that can form a bond through a chain polymerization reaction using a cation as a growth active species. The charge transporting polymer exhibits curability by containing a cationically polymerizable functional group. By curing the coating film formed using the charge-transporting polymer and forming an organic layer (also referred to as a "cured film" in this disclosure), the organic layer has a resistance for laminating an upper layer by a wet process. Can impart solvent properties.

Therefore, for example, when a charge-transporting polymer having a cationically polymerizable functional group is used to form a hole-transporting layer, the hole-transporting layer has solvent resistance. This makes it possible to form a light emitting layer as an upper layer using an ink composition or the like without dissolving the hole transport layer. Generally, the light-emitting layer is often coated with an aromatic hydrocarbon solvent. Therefore, the charge transporting polymer 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.

In a wet process, when the ink composition of the upper layer material is applied onto a coating film formed using a charge transporting polymer that does not have a polymerizable functional group, the components of the charge transporting polymer may be present in the ink composition of the upper layer material. It may be eluted to. Depending on the degree of elution, the elution of components of the charge transporting polymer can be one of the causes of an increase in driving voltage, a decrease in luminous efficiency, a decrease in life span, etc. of an organic electronic device.

Examples of cationically polymerizable functional groups include groups having carbon-carbon multiple bonds (e.g., vinyl group, allyl group, butenyl group, ethynyl group, etc.) and groups having small member rings (e.g., cyclopropyl group, cyclobutyl group, etc.). Cyclic alkyl groups; cyclic ether groups such as epoxy groups (oxiranyl groups) and oxetane groups (oxetanyl groups); cyclic thioether groups such as episulfide groups; cyclic ester groups such as diketene groups and lactone groups; cyclic amide groups such as lactam groups) Examples include. The cationic polymerizable functional group preferably contains one or more selected from the group consisting of a group having a carbon-carbon multiple bond and a group having a small member ring, and includes a group having a carbon-carbon double bond and a cyclic ether. It is more preferable to include one or more types selected from the group consisting of groups, and even more preferable to include one or more types selected from cyclic ether groups. As the group having a carbon-carbon double bond, a vinyl group and an allyl group are preferable, and a vinyl group is more preferable. As the cyclic ether group, an epoxy group and an oxetane group are preferable, and an oxetane group is more preferable. When the cationically polymerizable functional group contains a cyclic ether group, good curability tends to be obtained. The cationic polymerizable functional group may be a substituted or unsubstituted polymerizable functional group, and examples of substituents that the cationic polymerizable functional group can have include a methyl group, an ethyl group, and the like having 1 to 6 carbon atoms. Examples include alkyl groups.

The group PG includes an alkylene group having 4 to 30 carbon atoms. The cationically polymerizable functional group is bonded to the aromatic ring group via a linking group containing an alkylene group having 4 to 30 carbon atoms. When the group PG contains an alkylene group having 4 to 30 carbon atoms, the degree of freedom of the cationically polymerizable functional group increases, and the polymerization reaction can proceed more easily. The alkylene group may be linear, branched, or cyclic. From the viewpoint of improving solubility and curability, it is preferably linear.

The number of carbon atoms is 4 to 30 from the viewpoint of improving solubility and curability. The number of carbon atoms is preferably 5 or more, more preferably 6 or more. Further, the number of carbon atoms is preferably 20 or less, more preferably 15 or less, and still more preferably 10 or less. When the alkylene group has 4 or more carbon atoms, good solubility in solvents and good curability due to improved reactivity can be obtained. In addition, when the number of carbon atoms in the alkylene group is 30 or less, the solubility of the charge transporting polymer after curing is prevented from increasing, and when the upper layer material is laminated by a wet process, the organic layer is absorbed into the solvent of the upper layer material. Elution can be prevented.

Examples of the group PG include a group containing an oxetane group and an alkylene group having 4 to 30 carbon atoms, a group containing a vinyl group and an alkylene group having 4 to 30 carbon atoms, and the like.

Examples of the alkylene group include a tetramethylene group, a butane-1,3-diyl group, a pentamethylene group, a hexamethylene group, a heptamethylene group, an octamethylene group, a decamethylene group, a cyclohexane-diyl group, and the like.

The group PG may further include any divalent group. In one embodiment, the cationic polymerizable functional group is bonded to the aromatic ring group via a linking group containing an alkylene group having 4 to 30 carbon atoms and any divalent group. Examples of arbitrary divalent groups include oxy groups (ether bonds), oxymethylene groups, methyleneoxy groups, thio groups (thioether bonds), sulfonyl groups, substituted or unsubstituted imino groups, and substituted or unsubstituted boranediyl groups. (-BR- bond (R is a hydrogen atom or an alkyl group)), a carbonyl group, an oxycarbonyl group, a carbonyloxy group, a substituted or unsubstituted iminocarbonyl group, a substituted or unsubstituted carbonylimino group, and the like.

From the viewpoint of increasing the degree of freedom of the cationically polymerizable functional group and facilitating the polymerization reaction, the cationically polymerizable functional group and the aromatic ring group are bonded via a linking group containing an alkylene group having 4 to 30 carbon atoms. ing. The alkylene group is preferably a linear alkylene group. For example, when an organic layer is formed on an electrode, it is preferable that the linking group further includes a hydrophilic divalent group from the viewpoint of improving affinity with a hydrophilic electrode such as ITO. From the viewpoint of facilitating the acquisition or synthesis of the monomer used to introduce the cationically polymerizable functional group into the charge transporting polymer, an ether bond (oxy group), It may have a linking group containing one or more types selected from ester bonds (oxycarbonyl group or carbonyloxy group) and the like.

(aromatic ring group)
The "aromatic ring group" is preferably an aromatic ring group having 2 to 30 carbon atoms. Examples of aromatic rings include aromatic hydrocarbons and aromatic heterocycles. Furthermore, examples of aromatic rings include monocycles, fused polycyclic aromatic hydrocarbons, and fused polycyclic aromatic heterocycles. Examples of aromatic hydrocarbons include benzene, naphthalene, anthracene, tetracene (naphthacene), fluorene, phenanthrene, 9,10-dihydrophenanthrene, triphenylene, pyrene, chrysene, perylene, triphenylene, pentacene, benzopyrene, and the like. Examples of aromatic heterocycles include pyridine, pyrazine, quinoline, isoquinoline, carbazole, acridine, phenanthroline, furan, pyrrole, thiophene, oxazole, oxadiazole, thiadiazole, triazole, benzoxazole, benzoxadiazole, benzothiadiazole, and benzotriazole. , benzothiophene and the like. 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 examples of the substituent include R in the structural unit L described below (excluding groups containing a polymerizable functional group).

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.

(Structure example of terminal group P)
In one embodiment, an example of the terminal group P is a group represented by the following formula (P).

In the formula, Ar represents a substituted or unsubstituted aromatic ring group, and PG represents a group containing a cationically polymerizable functional group and an alkylene group having 4 to 30 carbon atoms. a represents an integer of 1 or more. "*" represents a binding site with another structure in the present disclosure.

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

In one embodiment, an example of the terminal group P is a group represented by the following formula (P1). The group represented by formula (P1) is a preferable group from the viewpoint of obtaining good solubility, curability, conductivity, and thermal stability.

In the formula, Ar represents a substituted or unsubstituted aromatic ring group, L represents a linking group containing an alkylene group having 4 to 30 carbon atoms, and PFG (Polymerizable Functional Group) represents a substituted or unsubstituted cationic polymerizable group. Represents a sexual functional group. a represents an integer of 1 or more.

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

In one embodiment, examples of the group represented by formula (P1) include a group represented by formula (P2) below. The group represented by formula (P2) is a preferable group from the viewpoint of obtaining good solubility, curability, conductivity, and thermal stability.

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 (X12), and Y represents a divalent group represented by any of the following formulas (Y1) to (Y12). l and n each independently represent 0 or 1, and m represents an integer of 4 to 30. a represents an integer of 1 or more.

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

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.

In one embodiment, the terminal group P preferably includes a group satisfying the following in formula (P2). Ar is an aromatic hydrocarbon group, l is 1, m is 4 to 30, n is 0 or 1, a is 1 or 2, and X is represented by formula (X12) It is the basis. Preferably, Ar is a benzene ring. m is preferably from 4 to 20, more preferably from 4 to 15, even more preferably from 4 to 10. It is preferable that n is 1. When n is 1, Y is preferably a group represented by formula (Y1) or formula (Y12), and more preferably a group represented by formula (Y12). PFG is preferably a group having a substituted or unsubstituted minor ring, or a group having a substituted or unsubstituted carbon-carbon multiple bond, and is a group having a substituted or unsubstituted minor ring. is more preferable. When PFG is a group having a substituted or unsubstituted small member ring, it is preferably a substituted or unsubstituted cyclic ether group, a substituted or unsubstituted oxetane group, or a substituted or unsubstituted epoxy group. More preferably, it is a substituted or unsubstituted oxetane group.

In one embodiment, the terminal group P preferably includes a group satisfying the following in formula (P2). Ar is an aromatic hydrocarbon group, l is 1, m is 4 to 30, n is 0 or 1, a is 1 or 2, and X is represented by formula (X1) It is the basis. Preferably, Ar is a benzene ring. m is preferably from 4 to 20, more preferably from 4 to 15, even more preferably from 4 to 10. It is preferable that n is 0. When n is 1, Y is preferably a group represented by formula (Y1) or formula (Y12). PFG is preferably a group having a substituted or unsubstituted minor ring, or a group having a substituted or unsubstituted carbon-carbon multiple bond, and is a group having a substituted or unsubstituted minor ring. is more preferable. When PFG is a group having a substituted or unsubstituted small member ring, it is preferably a substituted or unsubstituted cyclic ether group, a substituted or unsubstituted oxetane group, or a substituted or unsubstituted epoxy group. More preferably, it is a substituted or unsubstituted oxetane group.

In one embodiment, the terminal group P preferably includes a group satisfying the following in formula (P2). Ar is an aromatic hydrocarbon group, l is 0, m is 4 to 30, n is 0 or 1, and a is 1 or 2. Preferably, Ar is a benzene ring. m is preferably from 4 to 20, more preferably from 4 to 15, even more preferably from 4 to 10. It is preferable that n is 0. When n is 1, Y is preferably a group represented by formula (Y1) or formula (Y12). PFG is preferably a group having a substituted or unsubstituted small ring, or a group having a substituted or unsubstituted carbon-carbon multiple bond, and a group having a substituted or unsubstituted carbon-carbon multiple bond. It is more preferable that there be. When PFG is a group having a substituted or unsubstituted carbon-carbon multiple bond, it is more preferably a group having a substituted or unsubstituted carbon-carbon double bond, and is a substituted or unsubstituted vinyl group. More preferably.

Specific examples of the terminal group P are listed below. In this disclosure, the wavy line in the formula represents a bonding site with another structure.

In the formula, PFG represents a substituted or unsubstituted cationically polymerizable functional group, and n represents an integer of 4 to 30.

(Ratio of terminal group P, etc.)
The terminal group P is a group different from the terminal group S, and by having both groups at the terminals in a specific ratio, the charge transporting polymer has improved solubility in solvents and excellent curability. shows. Further, by using a charge transporting polymer having both groups at the terminals in a specific proportion, an organic layer exhibiting excellent solvent resistance, conductivity, and thermal stability can be obtained. From the viewpoint of obtaining better effects, the ratio of the terminal groups P is preferably 25 mol% or more, more preferably 30 mol% or more, and 35 mol% or more, based on the total of the terminal groups contained in the charge transporting polymer. is more preferable. From the viewpoint of obtaining particularly good curability, the content is preferably 40 mol% or more, more preferably 50 mol% or more. When the organic layer has excellent solvent resistance, components of the charge transporting polymer can be prevented from eluting into the ink composition when forming the upper layer. On the other hand, from the viewpoint of improving conductivity and heat resistance, the ratio of the terminal groups P is preferably 95 mol% or less, more preferably 90 mol% or less, based on the total terminal groups contained in the charge transporting polymer. It is more preferably 70 mol% or less, particularly preferably 60 mol% or less. The above range is also a preferable range from the viewpoint of preventing an increase in driving voltage due to a bonding site with a cationic polymerizable functional group and maintaining good charge transport properties of the organic layer.

Methods for confirming the curability of the charge transporting polymer and the solvent resistance of the organic layer include (1) residual film ratio test and (2) elution amount test. (1) In the residual film ratio test, the organic layer, which is a cured film formed using a charge transporting polymer, is immersed in a solvent, and the degree of curability and solvent resistance is confirmed from the rate of decrease in the film thickness of the organic layer. It's a method. (2) In the elution amount test, the organic layer, which is a cured film formed using a charge transporting polymer, is immersed in a solvent, and the curability and solvent resistance are determined from the amount of elution of the components of the charge transporting polymer into the solvent. This is a method to check the degree. (1) In the residual film rate test, the residual film rate can be determined by the ratio of the measured values of the film thickness of the organic layer or the ratio of the measured values of the absorbance of the organic layer. (1) Details of the residual film rate test will be described later. When the charge transporting polymer is cured by heating, it is possible to check the curability of the charge transporting polymer at low temperatures by changing the heating temperature.

The charge transporting polymer preferably shows a residual film rate of 80% or more in (1) residual film rate test, more preferably a residual film rate of 90% or more, still more preferably 95% or more, Particularly preferred is 97% or more. A charge transporting polymer into which terminal groups P and S are introduced tends to be cured at a low heating temperature, and the resulting organic layer exhibits high solvent resistance. Therefore, according to a preferred embodiment, the range of the remaining film rate is as follows: (1) In the remaining film rate test, the organic layer is formed by heating and the heating temperature is 150°C or 130°C. According to a more preferred embodiment, the residual film rate is (1) the residual film rate when the organic layer is formed by heating and the heating temperature is 130°C in the residual film rate test. be.

In the production of organic electronic devices, there are no limitations to the solvents used in the wet process, but generally aromatic hydrocarbon solvents such as toluene, aromatic ether solvents such as anisole, and aromatic ester solvents such as butyl benzoate are used. etc. are often used. It is preferable that the organic layer has at least solvent resistance to toluene. More preferably, it has solvent resistance to toluene and anisole, or toluene and butyl benzoate. Therefore, in (1) residual film ratio test and (2) elution amount test, it is preferable to use at least toluene as the solvent.

[Terminal group S]
The charge transporting polymer has, at the end of its molecular chain, a terminal group S containing an aromatic ring group substituted with a substituent SG that does not contain a cationically polymerizable functional group. In a wet process, a charge transporting polymer is dissolved in a solvent to create an ink composition. For example, if the charge transporting polymer does not contain a terminal group S, the solubility of the charge transporting polymer decreases, resulting in an increase in the dissolution time in the solvent, a decrease in the dissolved concentration, or, in some cases, insolubilization. Sometimes. As a result, in the wet process, processes such as heating are added during production of the ink composition, work time is increased, and productivity is reduced.

Examples of the substituent SG include a linear alkyl group; a branched or cyclic substituent; a polymerizable functional group other than a cationic polymerizable functional group, that is, a polymerizable functional group that does not exhibit cationic polymerizability. .

Examples of the terminal group S include a terminal group R containing an aromatic ring group substituted with a linear alkyl group, and a terminal group B containing an aromatic hydrocarbon group substituted with a branched or cyclic substituent. .

(Terminal group R)
In one embodiment, the charge transporting polymer has a terminal group R containing an aromatic ring group substituted with a linear alkyl group at the end of the molecular chain. The "linear alkyl group" here is an alkyl group that does not contain a branched structure or a cyclic structure, and is an unsubstituted alkyl group. A charge transporting polymer exhibits excellent solubility in a solvent by containing an aromatic ring group substituted with a linear alkyl group at the end of the molecular chain.

The number of carbon atoms in the linear alkyl group is preferably 6 or more, more preferably 7 or more, and 8 or more from the viewpoint of obtaining good solubility, curability, conductivity, and thermal stability. It is even more preferable that there be. Further, from the viewpoint of obtaining good solubility, curability, conductivity, and thermal stability, the number of carbon atoms in the linear alkyl group is preferably 20 or less, more preferably 12 or less, and 10 or less. It is more preferable that it is the following. Specific examples of the linear alkyl group include hexyl group, heptyl group, octyl group, nonyl group, decyl group, icosyl group, and the like. When the terminal group R contains a plurality of linear alkyl groups, the plurality of linear alkyl groups may be the same or different from each other.

The aromatic ring group is as described above. The aromatic ring is preferably an aromatic hydrocarbon from the viewpoint of commercial availability of a monomer for introducing the terminal group R and ease of synthesis.

In the terminal group R, a linear alkyl group is bonded to an aromatic ring group, and in the charge transporting polymer, the aromatic ring group is bonded to a molecular chain. The bonding position between the aromatic ring group and the molecular chain is not limited. Further, the bonding position of the linear alkyl group to the aromatic ring group is also not particularly limited. In one embodiment, the aromatic ring group has no substituents other than the linear alkyl group, considering the effect on solubility.

The "aromatic hydrocarbon group" is preferably an aromatic hydrocarbon group having 6 to 30 carbon atoms. Examples of aromatic hydrocarbons are listed above. When the aromatic hydrocarbon is a condensed polycyclic aromatic hydrocarbon, it is preferable that all the rings constituting the aromatic hydrocarbon are benzene rings.

The number of carbon atoms in the aromatic hydrocarbon group is 6 or more. From the viewpoint of commercial availability of monomers for introducing the terminal group R and ease of synthesis, the number of carbon atoms in the aromatic hydrocarbon group is preferably 18 or less, and from the viewpoint of solubility. , is more preferably 12 or less, and even more preferably 10 or less. The smaller the number of carbon atoms in the aromatic hydrocarbon group, the better the solubility tends to be.

Examples of aromatic hydrocarbon groups are shown below.

Specific examples of the terminal group R include a group represented by the following formula (R).

Each R independently represents a hydrogen atom or a straight-chain alkyl group, and at least one of R's is a straight-chain alkyl group.

In one embodiment, the terminal group R preferably includes a group satisfying the following in formula (R). R at the ortho and meta positions are all hydrogen atoms, and R at the para position is a linear alkyl group. The linear alkyl group that is R at the para position preferably has 6 or more carbon atoms, more preferably 7 or more carbon atoms, and still more preferably 8 or more carbon atoms. Further, the linear alkyl group that is R at the para position preferably has 20 or less carbon atoms, more preferably 12 or less carbon atoms, and even more preferably 10 or less carbon atoms.

(Terminal group B)
In one embodiment, the charge transporting polymer has a terminal group B containing an aromatic hydrocarbon group substituted with a branched or cyclic substituent at the end of the molecular chain. Regarding the carbon atoms constituting the ring of an aromatic hydrocarbon group, a branched or cyclic substituent is defined as 1+2n( when the carbon atom bonded to the molecular chain is numbered 1 and adjacent carbon atoms are numbered in order) n is an integer of 1 or more.) is preferably bonded to a carbon atom.

A "branched or cyclic substituent" is a substituent containing a branched structure, a cyclic structure, or both. In a preferred embodiment, the charge-transporting polymer contains an aromatic hydrocarbon group at the end of the molecular chain in which a hydrogen atom bonded to a specific carbon atom is substituted with a branched or cyclic substituent, so that the charge-transporting polymer can be easily transferred to a solvent. It shows excellent solubility. In this embodiment, it is speculated that the presence of bulky substituents attached to specific carbon atoms improves the solubility of the charge transporting polymer.

The branched or cyclic substituent is preferably an organic group, more preferably a hydrocarbon group, and even more preferably an alkyl group. In the present disclosure, hydrocarbon groups and alkyl groups as "branched or cyclic substituents" are unsubstituted. An organic group refers to an atomic group having one or more carbon atoms. The number of carbon atoms in the branched alkyl group is 3 or more, and preferably 4 or more from the viewpoint of solubility and heat durability. Further, from the same viewpoint, the number of carbon atoms in the branched alkyl group is preferably 10 or less, more preferably 8 or less, and even more preferably 6 or less. Specific examples of the branched alkyl group include branched propyl groups such as isopropyl group and isobutyl group; branched butyl groups such as sec-butyl group and tert-butyl group; branched pentyl group and branched hexyl group. In one embodiment, the branched alkyl group is preferably a group having a branched structure containing a carbon atom that serves as a starting point for branching in three directions (that is, a carbon atom to which no hydrogen atom is bonded). The number of carbon atoms in the cyclic alkyl group is preferably 5 or more, more preferably 6 or more from the viewpoint of solubility and heat durability. Further, from the same viewpoint, the number of carbon atoms in the cyclic alkyl group is preferably 10 or less, more preferably 8 or less, and even more preferably 7 or less. Examples of the cyclic alkyl group include a cyclohexyl group and a cycloheptyl group. When the number of carbon atoms in the alkyl group is 10 or less, good thermal stability can be obtained, a decrease in conductivity due to overheating can be prevented, and a sufficient margin can be ensured in the heating conditions. In addition, since intramolecular and intermolecular interactions of the charge transporting polymer are suppressed and movement of the charge transporting polymer is not restricted, good solubility can be obtained. The branched or cyclic substituent is preferably a branched alkyl group, more preferably a branched butyl group, and even more preferably a tert-butyl group. When the terminal group B contains a plurality of branched or cyclic substituents, the plurality of branched or cyclic substituents may be the same or different from each other.

The "aromatic hydrocarbon group" is as described above. In the terminal group B, a branched or cyclic substituent is bonded to an aromatic hydrocarbon group, and in the charge transporting polymer, the aromatic hydrocarbon group is bonded to a molecular chain. The bonding position between the aromatic hydrocarbon group and the molecular chain is not limited.

Regarding the carbon atoms constituting the ring of an aromatic hydrocarbon group, a branched or cyclic substituent is defined as 1+2n( when the carbon atom bonded to the molecular chain is numbered 1 and adjacent carbon atoms are numbered in order) n is an integer of 1 or more.) is bonded to a carbon atom. The upper limit of n is determined according to the number of carbon atoms constituting the ring of the aromatic hydrocarbon group. In this disclosure, the number assigned to a carbon atom is also referred to as a "substitution position number." The replacement position numbers are assigned as follows.

(1) The substitution position number of the carbon atom constituting the ring of the aromatic hydrocarbon group and bonded to the molecular chain is set to 1 (starting point).
(2) Starting from the carbon atom at substitution position number 1, proceed in one direction along the outer periphery of the aromatic hydrocarbon group, and number each adjacent carbon atom in order.

Examples of aromatic hydrocarbon groups in which carbon atoms are numbered at substitution positions are shown below.

In the terminal group B, at least one branched or cyclic substituent is bonded to the carbon atom at substitution position number 1+2n. The position of substitution position number 1+2n corresponds to a position where an electron localization structure cannot be described when describing the resonance structure of the terminal group B. Note that the resonance structure of the terminal group B is described in a state in which the aromatic hydrocarbon group is bonded to a molecular chain that can donate electrons to the aromatic hydrocarbon group. For example, the resonance structure of the terminal group B is described in a state where the structure at the end of the molecular chain is an aromatic ring (for example, a benzene ring) and an aromatic hydrocarbon group is bonded to the aromatic ring. Examples of resonance structures are shown below. In the formula, BG (Bulky Group) represents a branched or cyclic substituent.

(Substitution position number 2n: when localized structure can be described)
When describing the resonance structure of terminal group B, when the substitution position number of the carbon atom bonded to the molecular chain is 1, the position of substitution position number 2n (n is an integer of 1 or more) (i.e., 2n is an even number) can describe the localized structure. The following is an example having a branched or cyclic substituent on the carbon atom at substitution position number 2n (n=2).

(Substitution position number 1+2n: When localized structure cannot be described)
When describing the resonance structure of terminal group B, when the substitution position number of the carbon atom bonded to the molecular chain is 1, the position of substitution position number 1+2n (n is an integer of 1 or more) (i.e., 1+2n is an odd number) However, it is not possible to show a localized structure. The following is an example in which the carbon atom at substitution position number 1+2n (n=1) has a branched or cyclic substituent, and the carbon atom at substitution position number 1+2n (n=1) and substitution position number 1+2n (n=2). This is an example in which each has a branched or cyclic substituent.

In the terminal group B, the presence or absence of a substituent on the carbon atom at substituent position number 2n (n is an integer of 1 or more) of the aromatic hydrocarbon group is not limited. In one embodiment, in consideration of the influence on solubility, the carbon atom at substitution position number 2n (n is an integer of 1 or more) of the aromatic hydrocarbon group has no substituent.

The terminal group B has a structure having a branched or cyclic substituent on the carbon atom at substitution position number 1+2n (n is an integer of 1 or more) of the aromatic hydrocarbon group. Specific examples of the terminal group B include groups represented by the following formulas (B1) to (B5). However, the terminal group B is not limited to these, and includes an aromatic hydrocarbon group substituted with a branched or cyclic substituent, and the substitution position number of the aromatic hydrocarbon group is 1+2n (n is , an integer of 1 or more), there are no limitations on the bonding position and number of the branched or cyclic substituents, as long as the structure is satisfied in which the branched or cyclic substituents are bonded to carbon atoms. Considering improvement in solubility, the number of branched or cyclic substituents is preferably two or more. Considering the improvement in solubility, a group represented by any one of formulas (B1) to (B5) is preferable, a group represented by formula (B1) or formula (B2) is more preferable, and a group represented by formula (B2) is more preferable. A group represented by is more preferable.

In the formula, BG represents a branched or cyclic substituent.

Specific examples of BG include the following substituents. However, it is not limited to these. BG is preferably -C(CH ₃ ) ₃ .

From the viewpoint of imparting excellent solubility to the charge transporting polymer, the ratio of the terminal groups S is preferably 5 mol% or more, more preferably 10 mol% or more, based on the total number of terminal groups contained in the charge transporting polymer. It is preferably 30 mol% or more, more preferably 40 mol% or more, and particularly preferably 40 mol% or more. When the charge transporting polymer has excellent solubility, a sufficient margin can be ensured in the preparation conditions of the ink composition. On the other hand, from the viewpoint of imparting curability to the charge-transporting polymer, the ratio of the terminal group S is preferably 75 mol% or less, and 70 mol% or less, based on the number of moles at the terminal of the molecular chain of the charge-transporting polymer. More preferably, it is 65 mol% or less. From the viewpoint of imparting particularly good curability, the content is more preferably 60 mol% or less, and even more preferably 50 mol% or less.

In one embodiment, from the viewpoint of imparting excellent solubility to the charge transporting polymer, the ratio of the terminal groups R is preferably 50 mol% or more based on the total terminal groups S contained in the charge transporting polymer, More preferably 70 mol% or more, still more preferably 90 mol% or more. The upper limit may be 100 mol%.

In one embodiment, from the viewpoint of imparting excellent solubility to the charge transporting polymer, the ratio of the terminal groups B is preferably 50 mol% or more based on the total of the terminal groups S contained in the charge transporting polymer, More preferably 70 mol% or more, still more preferably 90 mol% or more. The upper limit may be 100 mol%.

Methods for confirming the solubility of charge transporting polymers include (1) dissolution time test and (2) dissolution concentration test. (1) The dissolution time test is a method in which a charge transporting polymer is dissolved in a solvent and the time required for dissolution is evaluated. (2) Dissolution concentration test is a method for evaluating the concentration at which a charge transporting polymer can be dissolved in a solvent. (1) Details of the dissolution time test will be described later. The charge transporting polymer preferably has at least good solubility in toluene. More preferably, it has good solubility in toluene and anisole, or toluene and butyl benzoate, and even more preferably, it has good solubility in toluene, anisole, and butyl benzoate. Therefore, in (1) dissolution time test and (2) dissolution concentration test, at least toluene is used as the solvent. Toluene and anisole and/or butyl benzoate may also be used.

[Structure of charge transporting polymer]
The charge transporting polymer may be linear or may have a branched structure. The charge-transporting polymer preferably includes 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 constituting a branch. Further, the charge transporting polymer preferably has charge transporting properties and includes at least a trivalent or higher structural unit B and a monovalent structural unit T constituting a branch, and further contains a divalent structural unit. But that's fine. The molecular chain has a chain structure containing a divalent structural unit and/or a trivalent or higher valent structural unit. Branched charge transporting polymers have excellent heat resistance and exhibit good solubility and curability because many terminal groups can be introduced therein. 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 a "monovalent" to "trivalent or more" bonding site.

Examples of partial structures contained in the charge transporting polymer include the following. The charge transporting polymer is not limited to polymers having the following partial structures. In the partial structure, "L" represents the structural unit L, "T" represents the structural unit T, and "B" represents the structural unit B. In the following, "*" represents a bonding site with another structural unit. In the following partial structures, a plurality of L's may be the same structural unit or different structural units. The same applies to T and B.

Linear charge transporting polymer

Branched charge transporting polymer

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, it has a structural unit B.

The charge transporting polymer preferably includes 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. These structures are preferably included in the structural unit L or the structural unit B. Moreover, it may be included in both the structural unit L and the structural unit B. By including any one of these structures, charge transport properties, particularly hole transport properties, are improved.

(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 one embodiment, the structural unit L is a substituted or unsubstituted aromatic amine structure, a carbazole structure, a thiophene structure, a bithiophene structure, a benzene structure, a fluorene structure, and a pyrrole structure, from the viewpoint of obtaining excellent hole transport properties. It is preferable to include one or more structures selected from the group consisting of a substituted or unsubstituted aromatic amine structure, a carbazole structure, a thiophene structure, a bithiophene structure, a benzene structure, and a fluorene structure. It is more preferable to include one or more 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.

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

Each R independently represents a hydrogen atom or a substituent. Preferably, R each independently represents -R ¹ , -OR ² , -SR ³ , -OCOR ⁴ , -COOR ⁵ , -SiR ⁶ R ⁷ R ⁸ , a halogen atom, and any polymerizable functional group. selected from the group consisting of: 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 heteroaryl group having 2 to 30 carbon atoms. An aryl group is an atomic group obtained by removing one hydrogen atom from an aromatic hydrocarbon. 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 heteroaryl group having 2 to 20 carbon atoms, and the aryl group or heteroaryl group may be further substituted with a linear, cyclic, or It may be substituted with a branched alkyl group. Since the charge transporting polymer exhibits good solubility and curability by having a specific terminal group, R is not particularly limited and can be selected according to the function required of the charge transporting polymer. can. For example, even when R is a halogen atom, the charge transporting polymer exhibits good solubility. R is preferably a hydrogen atom, a halogen 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 aromatic hydrocarbons include monocycles, fused rings, and polycycles in which two or more rings selected from monocycles and fused rings are bonded via a single bond. Examples of the aromatic heterocycle include a single ring, a condensed ring, and a polycycle in which two or more rings selected from a monocycle and a condensed ring are bonded via a single bond.

(Structural unit B)
Structural unit B is a trivalent or higher-valent structural unit that constitutes a branch when the charge transporting polymer has a branched structure. From the viewpoint of improving the durability of the organic electronics device, the structural unit B is preferably hexavalent or less, more preferably trivalent or tetravalent. The structural unit B is preferably 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.

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

W represents a trivalent linking group, for example, an arenetriyl group or a heteroarenetriyl group having 2 to 30 carbon atoms. An arenetriyl group is an atomic group obtained by removing three hydrogen atoms from an aromatic hydrocarbon. A heteroarenetriyl group is an atomic group obtained by removing three hydrogen atoms from an aromatic heterocycle. Ar each 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, for example, one hydrogen atom from a group having one or more hydrogen atoms among R in the structural unit L (excluding groups containing a polymerizable functional group). Examples include 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 an example of the substituent is R in the structural unit L.

(Structural unit T)
The structural unit T is a monovalent structural unit constituting the terminal end of the charge transporting polymer, and is a structural unit containing a terminal group. The structural unit T includes at least a structural unit TP containing a terminal group P and a structural unit TS containing a terminal group S. Furthermore, the structural unit T may include any structural unit TO different from the structural unit TP and the structural unit TS. The structural unit TO does not contain a terminal group P or a terminal group S.

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 (P).

The structural unit TS is a structural unit containing a terminal group S. The terminal group S explained above may be a structural unit TS, and examples of the structural unit TS include a group represented by formula (R) and a group represented by any one of formulas (B1) to (B5). The following groups are mentioned.

The structural unit TO is not particularly limited, and is selected from, for example, an unsubstituted aromatic hydrocarbon structure, an unsubstituted aromatic heterocyclic structure, and a structure containing one or more of these. In one embodiment, the structural unit TO is preferably an unsubstituted aromatic hydrocarbon structure, and preferably an unsubstituted benzene structure, from the viewpoint of imparting durability without reducing charge transportability. is more preferable. The structural unit TO is an aromatic ring structure substituted with a substituent containing a cationically polymerizable functional group, an aromatic heterocyclic structure substituted with a substituent containing a cationically polymerizable functional group, and one or two types thereof. The structure may be selected from structures including the above. However, the substituent containing a cationically polymerizable functional group does not contain an alkylene group having 4 to 30 carbon atoms. The structural unit TO may have the same structure as the structural unit L except for the valence.

(Polymerizable functional group)
In the charge transporting polymer, the polymerizable functional group is introduced at least as a cationically polymerizable functional group into the terminal portion (ie, the structural unit T) of the charge transporting polymer. Whether an arbitrary polymerizable functional group is introduced at the terminal end (i.e., structural unit T) or at a part other than the terminal end (i.e., structural unit L or B), It may be introduced in both parts. From the viewpoint of achieving both curability and charge transportability, it is preferable that the polymerizable functional group is introduced only at the terminal portion. In addition, 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, or may be introduced into both the main chain and the side chain. may have been introduced.

For example, the number of polymerizable functional groups per molecule of the charge transporting polymer is preferably two or more, more preferably three or more, from the viewpoint of obtaining a sufficient change in solubility. Further, the number of polymerizable functional groups is preferably 1,000 or less, more preferably 500 or less, from the viewpoint of maintaining charge transport properties.

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. In addition, 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 to the integral value of the entire spectrum in the ¹ H NMR (nuclear magnetic resonance) spectrum of the charge transport polymer, and the charge transport property. It can be calculated as an average value using the mass average molecular weight of the polymer. 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. From the viewpoint of excellent charge transport properties, the number average molecular weight is preferably 500 or more, more preferably 1,000 or more, even more preferably 2,000 or more, and even more preferably 3,000 or more. In addition, the number average molecular weight is preferably 200,000 or less, more preferably 100,000 or less, and 50,000 or less from the viewpoint of maintaining good solubility in the solvent and facilitating the preparation of the ink composition. More preferably, it is 20,000 or less, even more preferably.

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. From the viewpoint of excellent charge transport properties, the number average molecular weight is preferably 500 or more, more preferably 1,000 or more, even more preferably 2,000 or more, and even more preferably 5,000 or more. In addition, the number average molecular weight is preferably 1,000,000 or less, more preferably 100,000 or less, and 50,000 or less, from the viewpoint of maintaining good solubility in the solvent and facilitating the preparation of the ink composition. The following is more preferable, and 30,000 or less is even more preferable.

(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 is preferably 1,000 or more, more preferably 3,000 or more, even more preferably 5,000 or more, and even more preferably 10,000 or more, from the viewpoint of excellent charge transport properties. In addition, from the viewpoint of maintaining good solubility in solvents and facilitating the preparation of ink compositions, the mass average molecular weight is preferably 500,000 or less, more preferably 300,000 or less, and 150,000 or less. More preferably, it is 100,000 or less, and even more preferably 50,000 or less in this order.

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 is preferably 1,000 or more, more preferably 5,000 or more, even more preferably 10,000 or more, and even more preferably 30,000 or more, from the viewpoint of excellent charge transport properties. In addition, the mass average molecular weight is preferably 1,000,000 or less, more preferably 700,000 or less, and 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 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 curve.

(ratio of structural units)
When the charge-transporting polymer contains a structural unit L, the ratio of the structural unit L is preferably 10 mol% or more, more preferably 20 mol% or more, based on all structural units, from the viewpoint of obtaining sufficient charge-transporting properties. , more preferably 30 mol% or more. Further, the ratio of the structural unit L is preferably 97 mol% or less, more preferably 92 mol% or less, and even more preferably 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 ratio of structural units T contained in the charge transporting polymer is preferably 3 mol% or more, more preferably 8 mol% or more, and 15 mol% or more based on the total structural units. More preferred. 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. Further, from the viewpoint of obtaining sufficient charge transport properties, the ratio of the structural units T is preferably 60 mol% or less, more preferably 55 mol% or less, and even more preferably 50 mol% or less.

When the charge-transporting polymer contains structural unit B, the ratio of structural unit B is preferably 1 mol% or more, more preferably 5 mol% or more, based on all structural units, from the viewpoint of improving the durability of organic electronic devices. Preferably, 10 mol% or more is more preferable. In addition, the ratio of structural unit B is preferably 50 mol% or less, and 40 mol% or less, from the viewpoint of suppressing the increase in viscosity and favorably synthesizing the charge transporting polymer, or from the viewpoint of obtaining sufficient charge transporting property. is more preferable, and still more preferably 30 mol% or less.

Considering the balance of charge transportability, durability, productivity, etc., the ratio (molar ratio) of structural unit L and structural unit T is preferably L:T = 100:1 to 70, more preferably 100:3 to 50. Preferably, 100:5 to 30 is more preferable. Further, 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 L:T:B=100:10 to 200:10 to 100. The ratio is preferably 100:20 to 180:20 to 90, more preferably 100:40 to 160:30 to 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. Further, the ratio of the 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. Moreover, the ratio regarding the above-mentioned terminal groups can also be determined in the same manner.

The degree of polymerization (number of structural units) of the charge transporting polymer is preferably 5 or more, more preferably 10 or more, and even more preferably 20 or more, from the viewpoint of stabilizing the film quality of the coating film. Moreover, from the viewpoint of solubility in a solvent, the degree of polymerization is preferably 1,000 or less, more preferably 700 or less, and even more preferably 500 or less.

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. Further, it is also possible to use a catalyst species generated by using tris(dibenzylideneacetone)dipalladium(0), palladium(II) acetate, or the like as a precursor and mixing it 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.

<Charge transport material>
According to one embodiment, the charge transporting material contains at least the charge transporting polymer. Charge transporting materials can be preferably used as organic electronics materials. The charge transporting material may contain only one kind of the charge transporting polymer, or may contain two or more kinds. When the charge transporting material contains multiple types of charge transporting polymers, it is preferable that the entire mixture of charge transporting polymers satisfies the embodiments of the terminal groups P and S described above.

[Dopant]
The charge transporting material may further contain a dopant. The dopant is not particularly limited as long as it is a compound that can exhibit a doping effect and improve charge transport properties by being added to the charge transporting material. There are two types of doping: p-type doping and n-type doping. In p-type doping, a substance that acts as an electron acceptor is used as a dopant, and in n-type doping, a substance that acts as a dopant as an electron donor is used. It is preferable to perform p-type doping to improve hole transport properties, and n-type doping to improve electron transport properties. The dopant used in the charge transporting material may be a dopant that exhibits either p-type doping or n-type doping. Further, one type of dopant may be added alone, or a mixture of multiple types of dopants may be added.

The dopant used for p-type doping is an electron-accepting compound, and examples thereof include Lewis acids, protonic acids, transition metal compounds, ionic compounds, halogen compounds, and π-conjugated compounds. Specifically, Lewis acids include FeCl ₃ , PF ₅ , AsF ₅ , SbF ₅ , BF ₅ , BCl ₃ , BBr ₃ and the like; protonic acids include HF, HCl, HBr, HNO ₃ , H ₂ SO ₄ , HClO ₄ and other inorganic acids, benzenesulfonic acid, p-toluenesulfonic acid, dodecylbenzenesulfonic acid, polyvinylsulfonic acid, methanesulfonic acid, trifluoromethanesulfonic acid, trifluoroacetic acid, 1-butanesulfonic acid, vinylphenylsulfonic acid , organic acids such as camphorsulfonic acid; transition metal compounds include FeOCl, TiCl ₄ , _ZrCl 4 , HfCl ₄ , NbF ₅ , AlCl ₃ , NbCl ₅ , TaCl ₅ , MoF ₅ ; ionic compounds include tetrakis (pentafluoro phenyl)borate ion, tris(trifluoromethanesulfonyl)methide ion, bis(trifluoromethanesulfonyl)imide ion, hexafluoroantimonate ion, AsF ₆ ^- (hexafluoroarsenate ion), BF ₄ ^- (tetrafluoroborate ion), PF ₆ ^- Salts having perfluoroanions such as (hexafluorophosphate ion), salts having conjugated bases of the protonic acids as anions; examples of halogen compounds include Cl ₂ , Br ₂ , I ₂ , ICl, ICl ₃ , IBr, IF, etc.; π-conjugated compounds include TCNE (tetracyanoethylene), TCNQ (tetracyanoquinodimethane), and the like. Preferred are Lewis acids, ionic compounds, π-conjugated compounds, etc., and more preferred are ionic compounds. Among the ionic compounds, onium salts are particularly preferred. Onium salt means a compound consisting of a cation part containing onium ions such as iodonium and ammonium, and an anion part.

The dopants used for n-type doping are electron-donating compounds, such as alkali metals such as Li and Cs; alkaline earth metals such as Mg and Ca; alkali metals such as LiF and Cs ₂ CO ₃ and/or Examples include salts of alkaline earth metals; metal complexes; and electron-donating organic compounds.

[Cationic polymerization initiator]
The charge transporting material may further contain a cationic polymerization initiator in order to polymerize the charge transporting polymer having a terminal group P. The cationic polymerization initiator is not particularly limited, and examples thereof include protonic acids, Lewis acids, onium salts, and the like. Examples of these are given above.

From the viewpoint of curing the charge transporting polymer and obtaining good conductivity of the organic layer, it is preferable to use a compound that can act as a polymerization initiator for the cationically polymerizable functional group as the dopant. Examples of such compounds include a compound represented by the following formula (1) and a compound represented by the following formula (2).

(Compound represented by formula (1))

[In formula (1), R ^a to R ^c each independently represent a hydrogen atom (H), an alkyl group, or a benzyl group, and N does not bond to an aryl group. A represents an anion. ]

N bonds with a hydrogen atom (H), an alkyl group, or a benzyl group, but does not bond with an aryl group. This tends to improve stability against heat and light.

R ^a to R ^c may be the same or different. R ^a to R ^c may be connected to form a ring. The alkyl group may be linear, branched or cyclic, substituted or unsubstituted, and has, for example, 1 to 20 carbon atoms.

In one embodiment, from the viewpoint of improving solubility in a solvent, at least one of R ^a to R ^c is preferably an alkyl group or a benzyl group, and at least two of R ^a to R ^c are an alkyl group and/or a benzyl group. It is more preferable that R a to R c be a group, and all of R ^a to R ^c are preferably an alkyl group and/or a benzyl group.
In one embodiment, all of R ^a to R ^c are preferably alkyl groups from the viewpoint of improving thermal stability.
In one embodiment, from the viewpoint of improving solubility in aromatic hydrocarbon solvents, at least one of R ^a to R ^c preferably has 6 or more carbon atoms, more preferably 9 or more carbon atoms, and 12 It is more preferable that it is above.

In formula (1), A is not particularly limited as long as it is a conventionally known anion, but anions represented by the following formulas (1A) to (5A) improve characteristics such as reduced driving voltage and stable long-term driving. preferred from the viewpoint of

[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), 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 X or Y in the above formula (P2). R ¹ to R ¹⁶ each independently represents 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, 1 to 10 carbon atoms, preferably 1 to 6 carbon atoms); haloaryl group in which an aryl group such as a pentafluorophenyl group is substituted with a halogen atom (for example, 6 to 20 carbon atoms, preferably (6 to 12 carbon atoms); haloarylalkyl groups (for example, 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.

(Compound represented by formula (2))

[R ¹ and R ² each independently represent a hydrogen atom or an organic group, and A represents an anion. ]

R ¹ and R ² are each independently a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an arylalkyl group, an aryl group, or a heteroaryl group from the viewpoint of stability of the ionic compound, solubility in a solvent, etc. It is preferable that These groups may have a substituent. R ¹ and R ² may be bonded to each other to form a ring. At least one group selected from R ¹ and R ² is preferably an organic group, more preferably both R ¹ and R ² are organic groups, and even more preferably an aryl group. A is not particularly limited as long as it is a conventionally known anion, but anions represented by the above formulas (1A) to (5A) are preferred from the viewpoint of improving characteristics such as reduced driving voltage and stable long-term driving.

Specific examples of onium salts include the following compounds.

[Other optional ingredients]
The charge-transporting material may further contain a charge-transporting low-molecular compound, other polymers, and the like.

[Content]
From the viewpoint of obtaining good charge transport properties, the content of the charge transporting 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 transporting material. More preferred. It is also possible to set it to 100% by mass.

When containing a dopant, its content is preferably 0.01% by mass or more, and 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 content is more preferably 0.5% by mass or more, and even more preferably 0.5% by mass or more. Further, from the viewpoint of maintaining good film formability, the amount is preferably 50% by mass or less, more preferably 30% by mass or less, and even more preferably 20% by mass or less, based on the total mass of the charge transporting material.

When containing a cationic polymerization initiator, the content thereof is preferably 0.01% by mass or more, based on the total mass of the charge transporting material, from the viewpoint of improving the charge transportability of the charge transporting material. It is more preferably 1% by mass or more, and even more preferably 0.5% by mass or more. Further, from the viewpoint of maintaining good film formability, the amount is preferably 50% by mass or less, more preferably 30% by mass or less, and even more preferably 20% by mass or less, based on the total mass of the charge transporting material.

<Ink composition>
According to one embodiment, the ink composition contains the charge transporting 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 preferably such that the content of the charge transporting polymer is 0.1% by mass or more, more preferably 0.2% by mass or more, and 0.5% by mass. The amount above is more preferable. The content of the solvent is preferably such that the content of the charge transporting polymer is 20% by mass or less, more preferably 15% by mass or less, and even more preferably 10% by mass or less. preferable.

<Organic layer>
According to one embodiment, the organic layer is a layer formed using the charge transporting 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 thickness of the organic layer after curing is preferably 0.1 nm or more, more preferably 1 nm or more, and even more preferably 3 nm or more, from the viewpoint of improving charge transport efficiency. Further, from the viewpoint of reducing electrical resistance, the thickness of the organic layer is preferably 300 nm or less, more preferably 200 nm or less, and even more preferably 100 nm or less.

The residual film rate of the organic layer is preferably 80% or more, more preferably 90% or more, even more preferably 95% or more, and particularly preferably 97% or more.

<Organic electronics device>
According to one embodiment, the organic electronic device comprises at least the organic layer. Examples of the organic electronics device include an organic EL device, an organic photoelectric conversion device, an organic transistor, and the like. 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]
According to one embodiment, an 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 charge transport 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 described above, these layers can be easily formed by using an ink composition containing a charge transporting material.

When the organic EL element has an organic layer formed using the charge transport material as a hole transport layer and further has a hole injection layer, a known material can be used for the hole injection layer. Further, when the organic EL element has an organic layer formed using the charge transporting 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 a charge transporting material in both the hole injection layer and the hole transport layer.

<Display element, lighting device, display device>
According to one embodiment, a 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.

Further, according to one embodiment, a lighting device includes the organic EL element. Furthermore, according to one embodiment, 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.

EXAMPLES Hereinafter, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to the following Examples.

<Synthesis of charge transporting polymer>
[Preparation of Pd catalyst solution]
Tris(dibenzylideneacetone)dipalladium (0.183 g, 0.200 mmol) was weighed out in a sample container at room temperature in a glove box under a nitrogen atmosphere, toluene (40.00 ml) was added, and the mixture was stirred for 10 minutes. Similarly, tris(tert-butyl)phosphine (0.324 g, 1.600 mmol) was weighed into a different sample container, toluene (10.00 ml) was added, and the mixture was stirred for 10 minutes. The resulting solutions were mixed and stirred at room temperature for 10 minutes to obtain a Pd catalyst solution. All solvents used in the preparation of the Pd catalyst solution were used after degassing with nitrogen bubbles supplied at a rate of 1 liter/min under a nitrogen atmosphere for 30 minutes or more to bring the oxygen concentration to 0.5% by volume.

[Synthesis of charge transporting polymer]
The monomers used in the synthesis are shown below.

A charge transporting polymer was synthesized as follows.
(Example 1-Polymer E1)
In a three-neck round bottom flask, L1 (2.767 g, 5.0 mmol), B1 (0.964 g, 2.0 mmol), T1 (0.385 g, 1.0 mmol), T4 (0.808 g, 3.0 mmol), Methyltri-n-octylammonium chloride (0.034 g, manufactured by Aliquat336/Alfa Aesar), toluene (40.78 ml), and 3.0 mol% potassium hydroxide aqueous solution (7.79 ml) were added.
A stirring bar was placed in a three-necked round-bottomed flask, and a reflux tube and a nitrogen supply line (nitrogen supply rate: 400 ml/min) were attached. Using an oil bath as a heat source, stirring was performed at 60° C. for 30 minutes to dissolve the above materials.
The separately prepared Pd catalyst solution (1.01 ml) was added to this three-necked round bottom flask, and heated under reflux for 2 hours.
All solvents in the synthesis were used after degassing with nitrogen bubbles supplied at a rate of 1 l/min under a nitrogen atmosphere for 30 minutes or more to reduce the oxygen concentration to 0.5% by volume or less.

After the reaction was completed, the obtained organic layer was washed with water, then added to methanol-water (9:1), and the resulting precipitate was suction-filtered.
The obtained precipitate and ethyl acetate (125 ml) were added to an eggplant flask, a stirrer was placed there, and a nitrogen supply line (nitrogen supply amount: 400 ml/min) was attached. Using an oil bath as a heating source, stirring was performed at 60° C. for 15 minutes, and the precipitate was washed with ethyl acetate. After washing, the washed precipitate was collected by suction filtration. Using this washed precipitate, the same washing with ethyl acetate as above was further carried out twice to remove residual monomers and reactants soluble in ethyl acetate in the precipitate. Then, the precipitate washed with ethyl acetate was vacuum dried (40°C).
In an eggplant flask, add the vacuum-dried precipitate, a metal adsorbent consisting of mercaptopropylsilane and amorphous silica (20% by mass based on the precipitate, "ISOLUTE Si-Thiol" manufactured by Biotage Japan Co., Ltd.), and toluene (precipitate). 10% by mass) was added, a stirrer was put in, and a nitrogen supply line (nitrogen supply rate: 400 ml/min) was attached. Using a water bath as a heat source, stirring was performed at 40° C. with a stirrer to dissolve the precipitate, and stirring was further performed for 2 hours to perform adsorption treatment with a metal adsorbent.
After the adsorption treatment, the resulting mixed solution was filtered using a polytetrafluoroethylene (PTFE) filter (pore size: 0.2 μm) to remove the metal adsorbent.
The obtained filtrate was added to methanol, and the resulting precipitate was collected by suction filtration. Next, the recovered precipitate was vacuum-dried (40°C), and the mass was checked every hour and coarse particles were pulverized.The end point of vacuum drying was when there was no change in mass. ” was obtained.

The molar ratio of the terminal structural unit T in the obtained polymer E1 was 36.4 mol% based on the number of moles of all structural units. Further, the molar ratios of the structural unit TP and the structural unit TS were 25 mol% of the structural unit TP and 75 mol% of the structural unit TS, respectively, based on the total number of moles of the structural unit TP and the structural unit TS.
Moreover, the mass average molecular weight of the obtained polymer E1 was 45,500, and the number average molecular weight was 15,300.

The mass average molecular weight and number average molecular weight were measured by GPC (polystyrene equivalent) using tetrahydrofuran (THF) as an eluent. The measurement conditions are as follows.
Liquid delivery unit: LC-20AD Shimadzu Corporation UV-VIS detector: SPD-20A Shimadzu Corporation Detection wavelength: 254 nm
Column: Gelpack (registered trademark) GL-A160S/GL-A150S Hitachi Chemical Co., Ltd. Eluent: THF (for HPLC, contains stabilizer) Wako Pure Chemical Industries, Ltd. Flow rate: 1 ml/min
Column temperature: 40℃
Molecular weight standard material: Standard polystyrene (PStQuick B/C/D) Tosoh Corporation

(Example 2-Polymer E2)
In a three-neck round bottom flask, L1 (2.767 g, 5.0 mmol), B1 (0.964 g, 2.0 mmol), T1 (0.771 g, 2.0 mmol), T4 (0.538 g, 2.0 mmol), Methyl tri-n-octylammonium chloride (0.034 g, manufactured by Aliquat336/Alfa Aesar), toluene (41.77 ml), and 3.0 mol% potassium hydroxide aqueous solution (7.79 ml) were added.
Thereafter, a charge transporting polymer "Polymer E2" was prepared in the same manner as in Example 1. The mass average molecular weight of the obtained polymer E2 was 44,800, and the number average molecular weight was 15,500.

(Example 3 - Polymer E3)
In a three-neck round bottom flask, L1 (2.767 g, 5.0 mmol), B1 (0.964 g, 2.0 mmol), T1 (1.387 g, 3.6 mmol), T4 (0.108 g, 0.4 mmol), Methyl tri-n-octylammonium chloride (0.034 g, manufactured by Aliquat336/Alfa Aesar), toluene (43.34 ml), and 3.0 mol% potassium hydroxide aqueous solution (7.79 ml) were added.
Thereafter, a charge transporting polymer "Polymer E3" was prepared in the same manner as in Example 1. The obtained polymer E3 had a mass average molecular weight of 46,500 and a number average molecular weight of 15,100.

(Example 4-Polymer E4)
In a three-neck round bottom flask, L1 (2.767 g, 5.0 mmol), B1 (0.964 g, 2.0 mmol), T2 (0.683 g, 2.0 mmol), T4 (0.538 g, 2.0 mmol), Methyl tri-n-octylammonium chloride (0.034 g, manufactured by Aliquat336/Alfa Aesar), toluene (41.02 ml), and 3.0 mol% potassium hydroxide aqueous solution (7.79 ml) were added.
Thereafter, a charge transporting polymer "Polymer E4" was prepared in the same manner as in Example 1. The mass average molecular weight of the obtained polymer E4 was 51,100, and the number average molecular weight was 17,300.

(Example 5 - Polymer E5)
In a three-neck round bottom flask, L2 (2.576 g, 5.0 mmol), B1 (0.964 g, 2.0 mmol), T1 (0.771 g, 2.0 mmol), T4 (0.538 g, 2.0 mmol), Methyltri-n-octylammonium chloride (0.034 g, manufactured by Aliquat336/Alfa Aesar), toluene (40.15 ml), and 3.0 mol% potassium hydroxide aqueous solution (7.79 ml) were added.
Thereafter, a charge transporting polymer "Polymer E5" was prepared in the same manner as in Example 1. The mass average molecular weight of the obtained polymer E5 was 56,000, and the number average molecular weight was 16,100.

(Example 6 - Polymer E6)
In a three-neck round bottom flask, L2 (2.576 g, 5.0 mmol), B1 (0.964 g, 2.0 mmol), T1 (0.925 g, 2.4 mmol), T4 (0.431 g, 1.6 mmol), Methyltri-n-octylammonium chloride (0.034 g, manufactured by Aliquat336/Alfa Aesar), toluene (40.55 ml), and 3.0 mol% potassium hydroxide aqueous solution (7.79 ml) were added.
Thereafter, a charge transporting polymer "Polymer E6" was prepared in the same manner as in Example 1. The obtained polymer E6 had a mass average molecular weight of 55,500 and a number average molecular weight of 15,900.

(Example 7 - Polymer E7)
In a three-neck round bottom flask, L2 (2.576 g, 5.0 mmol), B1 (0.964 g, 2.0 mmol), T1 (1.079 g, 2.8 mmol), T4 (0.323 g, 1.2 mmol), Methyl tri-n-octylammonium chloride (0.034 g, manufactured by Aliquat336/Alfa Aesar), toluene (40.94 ml), and 3.0 mol% potassium hydroxide aqueous solution (7.79 ml) were added.
Thereafter, a charge transporting polymer "Polymer E7" was prepared in the same manner as in Example 1. The mass average molecular weight of the obtained polymer E7 was 54,800, and the number average molecular weight was 15,400.

(Example 8 - Polymer E8)
In a three-neck round bottom flask, L2 (2.576 g, 5.0 mmol), B1 (0.964 g, 2.0 mmol), T1 (0.771 g, 2.0 mmol), T5 (0.538 g, 2.0 mmol), Methyltri-n-octylammonium chloride (0.034 g, manufactured by Aliquat336/Alfa Aesar), toluene (40.15 ml), and 3.0 mol% potassium hydroxide aqueous solution (7.79 ml) were added.
Thereafter, a charge transporting polymer "Polymer E8" was prepared in the same manner as in Example 1. The mass average molecular weight of the obtained polymer E8 was 53,700, and the number average molecular weight was 14,900.

(Example 9 - Polymer E9)
In a three-neck round bottom flask, L1 (2.767 g, 5.0 mmol), B1 (0.964 g, 2.0 mmol), T1 (0.385 g, 1.0 mmol), T5 (0.808 g, 3.0 mmol), Methyltri-n-octylammonium chloride (0.034 g, manufactured by Aliquat336/Alfa Aesar), toluene (40.78 ml), and 3.0 mol% potassium hydroxide aqueous solution (7.79 ml) were added.
Thereafter, a charge transporting polymer "Polymer E9" was prepared in the same manner as in Example 1. The obtained polymer E9 had a mass average molecular weight of 47,500 and a number average molecular weight of 15,000.

(Example 10 - Polymer E10)
In a three-neck round bottom flask, L1 (2.767 g, 5.0 mmol), B1 (0.964 g, 2.0 mmol), T1 (0.771 g, 2.0 mmol), T5 (0.538 g, 2.0 mmol), Methyl tri-n-octylammonium chloride (0.034 g, manufactured by Aliquat336/Alfa Aesar), toluene (41.77 ml), and 3.0 mol% potassium hydroxide aqueous solution (7.79 ml) were added.
Thereafter, a charge transporting polymer "Polymer E10" was prepared in the same manner as in Example 1. The mass average molecular weight of the obtained polymer E10 was 47,000, and the number average molecular weight was 15,100.

(Example 11-Polymer E11)
In a three-neck round bottom flask, L1 (2.767 g, 5.0 mmol), B1 (0.964 g, 2.0 mmol), T1 (1.387 g, 3.6 mmol), T5 (0.108 g, 0.4 mmol), Methyl tri-n-octylammonium chloride (0.034 g, manufactured by Aliquat336/Alfa Aesar), toluene (43.34 ml), and 3.0 mol% potassium hydroxide aqueous solution (7.79 ml) were added.
Thereafter, a charge transporting polymer "Polymer E11" was prepared in the same manner as in Example 1. The mass average molecular weight of the obtained polymer E11 was 45,700, and the number average molecular weight was 14,900.

(Example 12-Polymer E12)
In a three-neck round bottom flask, L2 (2.576 g, 5.0 mmol), B1 (0.964 g, 2.0 mmol), T6 (0.563 g, 2.0 mmol), T5 (0.538 g, 2.0 mmol), Methyl tri-n-octylammonium chloride (0.034 g, manufactured by Aliquat336/Alfa Aesar), toluene (38.39 ml), and 3.0 mol% potassium hydroxide aqueous solution (7.79 ml) were added.
Thereafter, a charge transporting polymer "Polymer E12" was prepared in the same manner as in Example 1. The obtained polymer E12 had a mass average molecular weight of 46,000 and a number average molecular weight of 15,000.

(Comparative Example 1-Polymer C1)
In a three-neck round bottom flask, L1 (2.767 g, 5.0 mmol), B1 (0.964 g, 2.0 mmol), T1 (1.541 g, 4.0 mmol), methyltri-n-octylammonium chloride (0.034 g , Aliquat 336/Alfa Aesar), toluene (43.74 ml), and 3.0 mol% potassium hydroxide aqueous solution (7.79 ml) were added.
Thereafter, a charge transporting polymer "Polymer C1" was prepared in the same manner as in Example 1. The mass average molecular weight of the obtained polymer C1 was 46,400, and the number average molecular weight was 15,000.

(Comparative Example 2-Polymer C2)
In a three-neck round bottom flask, L1 (2.767 g, 5.0 mmol), B1 (0.964 g, 2.0 mmol), T1 (0.308 g, 0.8 mmol), T4 (0.862 g, 3.2 mmol), Methyl tri-n-octylammonium chloride (0.034 g, manufactured by Aliquat336/Alfa Aesar), toluene (40.59 ml), and 3.0 mol% potassium hydroxide aqueous solution (7.79 ml) were added.
Thereafter, a charge transporting polymer "Polymer C2" was prepared in the same manner as in Example 1. The mass average molecular weight of the obtained polymer C2 was 45,200, and the number average molecular weight was 15,300.

(Comparative Example 3-Polymer C3)
In a three-neck round bottom flask, L1 (2.767 g, 5.0 mmol), B1 (0.964 g, 2.0 mmol), T2 (1.365 g, 4.0 mmol), methyltri-n-octylammonium chloride (0.034 g , Aliquat 336/Alfa Aesar), toluene (42.24 ml), and 3.0 mol% potassium hydroxide aqueous solution (7.79 ml) were added.
Thereafter, a charge transporting polymer "Polymer C3" was prepared in the same manner as in Example 1. The mass average molecular weight of the obtained polymer C3 was 52,000, and the number average molecular weight was 16,800.

(Comparative Example 4-Polymer C4)
In a three-neck round bottom flask, L1 (2.767 g, 5.0 mmol), B1 (0.964 g, 2.0 mmol), T3 (1.085 g, 4.0 mmol), methyltri-n-octylammonium chloride (0.034 g , Aliquat 336/Alfa Aesar), toluene (39.87 ml), and 3.0 mol% potassium hydroxide aqueous solution (7.79 ml) were added.
Thereafter, a charge transporting polymer "Polymer C4" was prepared in the same manner as in Example 1. The mass average molecular weight of the obtained polymer C4 was 58,800, and the number average molecular weight was 15,400.

(Comparative Example 5-Polymer C5)
In a three-neck round bottom flask, L1 (2.767 g, 5.0 mmol), B1 (0.964 g, 2.0 mmol), T3 (0.542 g, 2.0 mmol), T4 (0.538 g, 2.0 mmol), Methyltri-n-octylammonium chloride (0.034 g, manufactured by Aliquat 336/Alfa Aesar), toluene (39.83 ml), and 3.0 mol% potassium hydroxide aqueous solution (7.79 ml) were added.
Thereafter, a charge transporting polymer "Polymer C5" was prepared in the same manner as in Example 1. The mass average molecular weight of the obtained polymer C5 was 51,500, and the number average molecular weight was 15,000.

(Comparative Example 6-Polymer C6)
In a three-neck round bottom flask, L2 (2.576 g, 5.0 mmol), B1 (0.964 g, 2.0 mmol), T1 (1.541 g, 4.0 mmol), methyltri-n-octylammonium chloride (0.034 g , Aliquat 336/Alfa Aesar), toluene (42.12 ml), and 3.0 mol% potassium hydroxide aqueous solution (7.79 ml) were added.
Thereafter, a charge transporting polymer "Polymer C6" was prepared in the same manner as in Example 1. The mass average molecular weight of the obtained polymer C6 was 53,000, and the number average molecular weight was 15,700.

(Comparative Example 7-Polymer C7)
In a three-neck round bottom flask, L1 (2.767 g, 5.0 mmol), B1 (0.964 g, 2.0 mmol), T1 (0.308 g, 0.8 mmol), T5 (0.862 g, 3.2 mmol), Methyl tri-n-octylammonium chloride (0.034 g, manufactured by Aliquat336/Alfa Aesar), toluene (40.59 ml), and 3.0 mol% potassium hydroxide aqueous solution (7.79 ml) were added.
Thereafter, a charge transporting polymer "Polymer C7" was prepared in the same manner as in Example 1. The mass average molecular weight of the obtained polymer C7 was 48,200, and the number average molecular weight was 16,000.

Tables 1 and 2 show the molar ratio (%) of the structural unit T contained in polymers E1 to E12 and polymers C1 to C7, and the molecular weights of polymers E1 to E12 and polymers C1 to C7.

<Solubility evaluation>
The solubility of polymers E1 to E12 and polymers C1 to C7 in solvents was evaluated in accordance with the following.

[Solubility in toluene]
(Dissolution time test)
Coarse particles contained in the polymer were ground using a mortar to form the polymer into powder with a constant particle size. Weigh out the polymer (8.7 mg) into a 6 ml screw tube so that the polymer content is 1.0% by mass based on the mass of the solution and the volume of the solution is 1 ml, and add toluene (865.0 mg) (25°C). ) was added. Subsequently, a stirring bar (10×Φ4 mm) was added, and the mixture was stirred (600 rpm) in a water bath (25° C.).
The dissolution time from the start of stirring until the polymer was completely dissolved was measured. A "completely dissolved" state was determined by visual inspection when there was no clearly undissolved polymer, there was no turbidity, and the solution was transparent.
In the Examples, the term "powder having a constant particle size" refers to a powder having an average particle size on a volume basis of 20 to 40 μm. The average particle size is the median diameter measured by a laser diffraction scattering type particle size distribution measuring device.

The measured dissolution time was evaluated on the following six levels.
A: Dissolution time less than 4.0 min B: Dissolution time 4.0 min or more and less than 5.0 min C: Dissolution time 5.0 min or more but less than 6.0 min D: Dissolution time 6.0 min or more but less than 7.0 min E: Dissolution time 7. 0 min or more and less than 8.0 min F: Dissolution time 8.0 min or more

The results of solubility evaluation are shown in Tables 3 and 4.

<Curability evaluation>
According to the following, an organic layer was formed using polymers E1 to E12 and polymers C1 to C7, and the curability of the polymer (solvent resistance of the organic layer) was evaluated.

(Residual film rate test)
(130℃)
A polymer (50.0 mg) and the following polymerization initiator (0.5 mg) were weighed into a 9 ml screw tube, and toluene (4949.5 mg) was added to dissolve the polymer and polymerization initiator to prepare an ink composition. The ink composition was filtered through a polytetrafluoroethylene (PTFE) filter (pore size: 0.2 μm), and dropped onto a quartz substrate (length: 22 mm x width: 29 mm x thickness: 0.7 mm), and a coating film was formed using a spin coater. It was filmed. Subsequently, heat curing was performed at 130° C. for 30 minutes in the atmosphere to form an organic layer with a thickness of 30 nm on the quartz substrate.

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) for 10 minutes in a 25°C environment so that the organic layer after measurement was on the top. 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 residual film rate was evaluated in the following five stages. The higher the residual film rate, the higher the curability of the polymer and the higher the solvent resistance of the organic layer.
A: Remaining film rate 99% or more and 100% or less B: Remaining film rate 90% or more and less than 99% C: Remaining film rate 80% or more and less than 90% D: Remaining film rate 70% or more and less than 80% E: Remaining film rate 70 %less than

(150℃)
The residual film rate was evaluated in the same manner as above, except that the heat curing conditions were changed to 150° C. for 30 minutes in the atmosphere.

The results of the curability evaluation are shown in Tables 5 and 6.

The polymers of Examples had excellent solubility in organic solvents. Furthermore, the polymers of Examples had excellent curability, and the organic layer formed from the polymers of Examples had sufficient solvent resistance.

<Conductivity evaluation and thermal stability evaluation>
A device for evaluation (hole-only device (hereinafter referred to as "HOD")) was prepared using polymers E1 to E12 and polymers C1 to C7 according to the following, and conductivity and thermal stability were evaluated. A schematic cross-sectional view of the HOD is shown in FIG. In FIG. 1, 1 represents a substrate, 2 an anode, 3 an organic layer, and 4 a cathode.

[Preparation of HOD]
(Preparation of HOD for conductivity 1 evaluation)
A polymer (50.0 mg) and the following polymerization initiator (0.5 mg) were weighed into a 9 ml screw tube, and toluene (2449.5 mg) was added to dissolve the polymer and polymerization initiator to prepare an ink composition. The ink composition was filtered using a polytetrafluoroethylene (PTFE) filter (pore size: 0.2 μm). The ink composition was dropped onto a quartz substrate (22 mm long x 29 mm wide x 0.7 mm thick, hereinafter referred to as "ITO substrate") on which an indium tin oxide (ITO) electrode was formed patterned to a width of 1.6 mm, A coating film was formed using a spin coater. Subsequently, heat curing was performed at 130° C. for 30 minutes in the atmosphere to form an organic layer with a thickness of 100 nm on the ITO substrate.

Thereafter, the ITO substrate was transferred to a vacuum evaporation machine, and an aluminum (Al) electrode with a thickness of 100 nm was formed on the formed organic layer by evaporation, and a sealing process was performed to make the conductivity 1. An evaluation HOD was prepared.

(Preparation of HOD for conductivity 2 evaluation)
A HOD for conductivity 2 evaluation was produced in the same manner as the HOD for conductivity 1 evaluation, except that the heat curing conditions were changed to 150° C. for 30 minutes in the atmosphere.

(Preparation of HOD for thermal stability 1 evaluation)
After heating and curing, additional heating was performed at 200°C for 60 minutes in a nitrogen atmosphere to form an organic layer with a thickness of 100 nm on the ITO substrate. A HOD for thermal stability 1 evaluation was prepared.

(Preparation of HOD for thermal stability 2 evaluation)
After heating and curing, additional heating was performed at 200°C for 60 minutes in a nitrogen atmosphere to form an organic layer with a thickness of 100 nm on the ITO substrate. A HOD for thermal stability 2 evaluation was prepared.

[Conductivity evaluation]
A voltage was applied to the HOD for conductivity 1 evaluation and the HOD for conductivity 2 evaluation produced above, and the conductivity was evaluated.

The applied voltage was varied and the voltage at a current density of 300 mA/cm ² was measured. The conductivity was evaluated on the following four levels.
A: Voltage less than 2.0V B: Voltage 2.0V or more and less than 2.5V C: Voltage 2.5V or more and less than 3.0V D: Voltage 3.0V or more

[Thermal stability evaluation]
(Thermal stability 1 evaluation)
A voltage was applied to the HOD for thermal stability 1 evaluation prepared above, the applied voltage was varied, and the voltage at a current density of 300 mA/cm ² was measured. Based on the voltage difference between the HOD for conductivity 1 evaluation and the HOD for thermal stability 1 evaluation, thermal stability was evaluated in the following five stages. The voltage difference was calculated using the following formula. The smaller the voltage difference, the better the heat resistance.

A: Voltage difference less than 0.2V B: Voltage difference 0.2V or more and less than 0.5V C: Voltage difference 0.5V or more and less than 1.0V D: Voltage difference 1.0V or more and less than 1.5V E: Voltage difference 1. 5V or more

(Thermal stability 2 evaluation)
A voltage was applied to the HOD for thermal stability 2 evaluation prepared above, the applied voltage was varied, and the voltage at a current density of 300 mA/cm ² was measured. Based on the voltage difference between the HOD for conductivity 2 evaluation and the HOD for thermal stability 2 evaluation, thermal stability was evaluated in the following five stages. The voltage difference was calculated using the following formula. The smaller the voltage difference, the better the heat resistance.

A: Voltage difference less than 0.2V B: Voltage difference 0.2V or more and less than 0.5V C: Voltage difference 0.5V or more and less than 1.0V D: Voltage difference 1.0V or more and less than 1.5V E: Voltage difference 1. 5V or more

The results of conductivity evaluation and heat resistance evaluation are shown in Tables 7 and 8.

The organic layer formed by the example polymer had excellent electrical conductivity and thermal stability. An organic electronic device containing the organic layer exhibits excellent electrical conductivity and thermal stability.

According to one embodiment, the charge-transporting polymer is a polymeric material suitable for wet processing and can be preferably used in the fabrication of organic electronic materials using wet processing. Additionally, according to one embodiment, organic layers formed using charge transporting polymers can improve the properties of organic electronic devices.

1 Substrate 2 Anode 3 Organic layer 4 Cathode

Claims (13)

A terminal group P containing an aromatic ring group substituted by a group PG containing a cationically polymerizable functional group and an alkylene group having 4 to 30 carbon atoms, and an aromatic ring substituted by a substituent SG not containing a cationically polymerizable functional group has a terminal group S containing a group,
The terminal group S includes a group represented by the following formula (B2),

(In the formula, BG represents a branched or cyclic alkyl group.)
The terminal group S is a group represented by the formula (B2), in which BG is a branched alkyl group;
including,
A charge transporting polymer containing 25 to 95 mol% of the terminal group P based on all terminal groups. The charge transporting polymer according to claim 1, wherein the group PG includes a group containing an oxetanyl group and an alkylene group having 4 to 30 carbon atoms. The charge according to claim 1 or 2 , comprising one or more structures selected from the group consisting of a substituted or unsubstituted aromatic amine structure, a carbazole structure, a thiophene structure, a bithiophene structure, a benzene structure, and a fluorene structure. Transport polymer. The charge transporting polymer according to any one of claims 1 to 3 , having a structure branched in three or more directions. A charge transporting material comprising the charge transporting polymer according to any one of claims 1 to 4 . The charge transporting material according to claim 5 , further comprising a cationic polymerization initiator. An ink composition comprising the charge transporting polymer according to any one of claims 1 to 4 or the charge transporting material according to any one of claims 5 and 6 , and a solvent. Formed using the charge transporting polymer according to any one of claims 1 to 4 , the charge transporting material according to any one of claims 5 and 6 , or the ink composition according to claim 7 , organic layer. An organic electronic device comprising the organic layer according to claim 8 . An organic electroluminescent device comprising the organic layer according to claim 8 . A display element comprising the organic electroluminescent element according to claim 10 . A lighting device comprising the organic electroluminescent element according to claim 10 . A display device comprising the lighting device according to claim 12 and a liquid crystal element as a display means.

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