JP6946934B2 - Charge transport materials and organic electronics devices - Google Patents

Description

The present disclosure relates to charge transporting materials, ink compositions, organic layers, organic electronics elements, organic electroluminescence elements (also referred to as "organic EL elements"), display elements, lighting devices, and display devices.

Organic electronics devices are devices that perform electrical operations using organic substances, and are expected to exhibit features such as energy saving, low cost, and flexibility, and are attracting attention as a technology that can replace conventional silicon-based inorganic semiconductors. Has been done. Examples of the organic electronics element include an organic EL element, an organic photoelectric conversion element, an organic transistor and the like.

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

Organic EL elements are roughly classified into two types, low molecular weight organic EL elements using low molecular weight compounds and high molecular weight organic EL elements using high molecular weight compounds, according to the organic materials used. The organic EL element is manufactured mainly by a dry process in which film formation is performed in a vacuum system, a wet process in which film formation is performed by plated printing such as letterpress printing and intaglio printing, and plateless printing such as inkjet. It is roughly divided into two. A wet process is expected as an indispensable method for future large-screen organic EL displays because a simple film formation is possible as compared with a dry process that requires a vacuum system. Therefore, in recent years, the development of polymer compounds suitable for wet processes has been promoted.

On the other hand, with respect to the organic EL element, further improvement is desired in various element characteristics such as luminous efficiency. As a means for improving the performance of organic EL devices, attempts have been made to make the organic layers multi-layered and separate the functions in each layer. When the number of layers is increased according to the wet process, the solvent resistance of the lower layer to the solvent of the coating solution used for film formation of the upper layer is required.

As a method of forming multiple layers, for example, a method of using two kinds of compounds having different solubilities in water and an organic solvent as materials constituting adjacent layers is known. Specifically, water-soluble PEDOT: PSS is used as a compound that forms a lower layer such as a buffer layer and a hole injection layer, while toluene and the like are used as a compound that forms an upper layer such as a photoelectric conversion layer and a light emitting layer. There is a method of using a material soluble in the organic solvent of. Since the lower layer formed by PEDOT: PSS is insoluble in an organic solvent such as toluene, this method makes it possible to prepare a two-layer structure by a coating method.

However, in the method using water-soluble PEDOT: PSS, water tends to remain in the formed organic layer, and the characteristics of the organic layer may deteriorate. In addition, the materials that can be used are limited in the multi-layering.

As another method, a method of increasing the solvent resistance of the lower layer toward multi-layering is being studied. For example, studies have been conducted to form a multilayer structure using a compound having a polymerizable functional group (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2009-283509

In the method using a compound having a polymerizable functional group, for example, a material containing a polymerizable polymer, a polymerization initiator, and an organic solvent is used. Multi-layering can be achieved by applying this material, forming a lower layer cured by heating or the like, and forming an upper layer on the lower layer.

However, in this method, when the upper layer is formed using an organic solvent, if the lower layer does not have sufficient solvent resistance, a part of the lower layer may dissolve out, and a good multilayer structure can be formed. It can be difficult.

Therefore, in view of the above, it is an object of the present disclosure to provide a charge transporting material and an ink composition having improved curability. Another object of the present disclosure is to provide an organic layer suitable for forming a multilayer structure, and to provide an organic electronics element and an organic EL element having a multilayer structure. Furthermore, it is an object of the present disclosure to provide a display element, a lighting device, and a display device having various characteristics improved by using an organic electronic element or an organic EL element having a multi-layer structure.

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

One embodiment comprises a first charge-transporting polymer having one or more benzocyclobutenyl group-containing groups and a second charge-transporting polymer having one or more carbon-carbon unsaturated bond-containing groups. Regarding charge transporting materials.

According to one embodiment, the first charge-transporting polymer and the second charge-transporting polymer each have a structure branched in three or more directions.

According to one embodiment, the first charge transport polymer and the second charge transport polymer consist of a substituted or unsubstituted aromatic amine structure, a carbazole structure, a thiophene structure, and a fluorene structure, respectively. It has one or more structures selected from the group.

According to one embodiment, at least one of the one or more benzocyclobutenyl group-containing groups is present at the end of the first charge-transporting polymer and the one or more carbon-carbon unsaturated bond groups. At least one of the containing groups is present at the end of the second charge-transporting polymer.

（Ａｒは、置換又は非置換の芳香環を表し、Ｘは、２価の連結基を表し、Ｒ^ａ〜Ｒ^ｇは、それぞれ独立に、水素原子又は置換基を表す。ｌ〜ｍは整数を表し、ｌは０又は１、ｎは０又は１、ｍは１以上である。） According to one embodiment, the benzocyclobutenyl group-containing group contains a group represented by the following formula (4).

(Ar represents a substituted or unsubstituted aromatic ring, X represents a divalent linking group, Ra ^{a to} R ^g each independently represent a hydrogen atom or a substituent. L to m represent an integer. Represented, l is 0 or 1, n is 0 or 1, and m is 1 or more.)

（Ａｒは、置換又は非置換の芳香環を表し、Ｘは、２価の連結基を表し、Ｒ^ａ〜Ｒ^ｃは、それぞれ独立に、水素原子又は置換基を表す。ｌ〜ｍは整数を表し、ｌは０又は１、ｎは０又は１、ｍは１以上である。） According to one embodiment, the carbon-carbon unsaturated bond group-containing group includes a group represented by the following formula (9).

(Ar represents a substituted or unsubstituted aromatic ring, X represents a divalent linking group, Ra ^{a to} R ^c each independently represent a hydrogen atom or a substituent. L to m represent an integer. Represented, l is 0 or 1, n is 0 or 1, and m is 1 or more.)

According to one embodiment, any of the charge transporting materials is a hole injecting material or a hole transporting material.

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

Another embodiment relates to an organic electronic device having an organic layer formed by using any of the charge transporting materials or the ink composition.

Another embodiment relates to an organic electroluminescent device having any of the charge transporting materials or an organic layer formed using the ink composition.

Another embodiment relates to the organic electroluminescent device further comprising a flexible substrate.

Another embodiment relates to the organic electroluminescent device further comprising a resin substrate.

Another embodiment relates to a display device comprising any of the organic electroluminescent devices described above.

Another embodiment relates to a lighting device comprising any of the above organic electroluminescent devices.

Another embodiment relates to a display device including the lighting device and a liquid crystal element as a display means.

According to the present disclosure, it is possible to provide a charge transporting material and an ink composition having improved curability. Further, according to the present disclosure, it is possible to provide an organic layer suitable for forming a multilayer structure, and to provide an organic electronics element and an organic EL element having a multilayer structure. Further, according to the present disclosure, it is possible to provide a display element, a lighting device, and a display device having improved various characteristics by using an organic electronic element or an organic EL element having a multi-layer structure.

It is sectional drawing which shows an example of the organic EL element which is one Embodiment of this invention. The fluorescence spectrum of the organic layer prepared in the reference example is shown. The difference spectrum between the fluorescence spectrum of the organic layer prepared in Reference Example 1 and the fluorescence spectrum of the organic layer prepared in Reference Example 5 is shown. The fluorescence spectra of the organic layers prepared in Examples and Comparative Examples are shown. The difference spectrum between the fluorescence spectrum of the organic layer prepared in Example 11 and the fluorescence spectrum of the organic layer prepared in Example 15 is shown.

An embodiment of the present invention will be specifically described. The present invention is not limited to these embodiments.

<Charge transport material>
In one embodiment, the charge-transporting material contains at least two charge-transporting polymers capable of transporting charge and reacting with each other. At least two charge-transporting polymers are a first charge-transporting polymer having one or more benzocyclobutenyl group-containing groups and a second charge-transporting polymer having one or more carbon-carbon unsaturated bond-containing groups. Includes sex polymers. The charge-transporting material is excellent by containing a first charge-transporting polymer having a benzocyclobutenyl group-containing group and a second charge-transporting polymer having a carbon-carbon unsaturated bond group-containing group. Shows curability. In the present disclosure, the term "polymer" also includes "oligomer" which is a polymer having a low degree of polymerization. The charge transporting material can be preferably used as an organic electronics material.

In general, the polymerization of a compound having a vinyl group proceeds by an addition polymerization reaction by a double bond, and the polymerization of a compound having a benzocyclobutenyl group is an addition by a double bond generated by opening the ring of the benzocyclobutenyl group. It is considered that it proceeds by the polymerization reaction. Further, the compound having a vinyl group and the compound having a benzocyclobutenyl group can be substrates for a cycloaddition reaction such as a Diels-Alder reaction by opening the ring of the benzocyclobutenyl group-containing group by heating. The cycloaddition reaction between the benzocyclobutenyl group-containing group and the vinyl group-containing group proceeds at a lower temperature than the addition polymerization reaction between the benzocyclobutenyl group-containing groups or the vinyl group-containing groups. .. In addition, the cyclization addition reaction between the benzocyclobutenyl group-containing group and the vinyl group-containing group is a reaction as compared with the addition polymerization reaction between the benzocyclobutenyl group-containing groups or the vinyl group-containing groups. Tends to occur easily.

Therefore, when the first charge-transporting polymer having a benzocyclobutenyl group-containing group and the second charge-transporting polymer having a carbon-carbon unsaturated bond group-containing group are used in combination, cyclization It is considered that as the addition reaction proceeds, sufficient insolubilization (curing) of the organic layer can be achieved as compared with the case where each of them is polymerized alone.

If the first charge-transporting polymer having a benzocyclobutenyl group-containing group and the second charge-transporting polymer having a carbon-carbon unsaturated bond group-containing group are used in combination, the polymerization reaction proceeds efficiently. , Sufficient insolubilization can be performed without including a large amount of benzocyclobutenyl group-containing group or carbon-carbon unsaturated bond group-containing group in the polymer.

Further, as a polymerizable polymer, a polymer having an oxetane group or an epoxy group is known. Generally, in the polymerization of a compound having an oxetane group or an epoxy group, an oxetane group or an epoxy group opened by an active species generated from a polymerization initiator with heating attacks an unopened oxetane group or an epoxy group and is added. Proceed by doing. When a polymer having an oxetane group or an epoxy group is used as the polymerizable polymer, heating is performed using a polymerization initiator in order to sufficiently insolubilize the polymer. On the other hand, a polymerization initiator is obtained by using a first charge-transporting polymer having a benzocyclobutenyl group-containing group and a second charge-transporting polymer having a carbon-carbon unsaturated bond group-containing group in combination. It is possible to perform sufficient insolubilization without using.

In a charge-transporting material containing a first charge-transporting polymer having a benzocyclobutenyl group-containing group and a second charge-transporting polymer having a carbon-carbon unsaturated bond group-containing group, the content ratio of both. Can be appropriately selected according to the intended use. It is preferable to adjust the contents of the first charge-transporting polymer and the second charge-transporting polymer in consideration of the molar ratio of the benzocyclobutenyl group-containing group and the carbon-carbon unsaturated bond group-containing group. ..

In one embodiment, the ratio (molar ratio) of the benzocyclobutenyl group-containing group / carbon-carbon unsaturated bond group-containing group is preferably 0.05 or more, and is 0, from the viewpoint of efficiently proceeding the Diels-Alder reaction. .1 or more is more preferable, and 0.2 or more is further preferable. Further, from the viewpoint of efficiently advancing the Diels-Alder reaction, the ratio (molar ratio) of the benzocyclobutenyl group-containing group / carbon-carbon unsaturated bond group-containing group is preferably 20 or less, more preferably 10 or less. 4 or less is more preferable.

In one embodiment, the ratio of benzocyclobutenyl group-containing groups is preferably high from the viewpoint of obtaining high curability. The ratio (molar ratio) of the benzocyclobutenyl group-containing group / (benzocyclobutenyl group-containing group + carbon-carbon unsaturated bond-containing group) is preferably 0.5 or more, more preferably 0.6 or more. 0.8 or more is more preferable. From the viewpoint of improving curability, the ratio (molar ratio) of the benzocyclobutenyl group-containing group / (benzocyclobutenyl group-containing group + carbon-carbon unsaturated bond group-containing group) is 0.99 or less. Preferably, it is 0.95 or less, more preferably 0.92 or less.

In one embodiment, the ratio of carbon-carbon unsaturated bond group-containing groups is preferably high from the viewpoint of suppressing the change in the fluorescence spectrum before and after curing of the organic layer. The organic layer formed by using the first charge-transporting polymer having a benzocyclobutenyl group-containing group tends to have a change in the fluorescence spectrum before and after curing. From the viewpoint of facilitating the design of organic electronic devices, it may be desirable to suppress changes in the fluorescence spectrum. The ratio (molar ratio) of the benzocyclobutenyl group-containing group / (benzocyclobutenyl group-containing group + carbon-carbon unsaturated bond-containing group) is preferably 0.5 or less, more preferably 0.4 or less. 0.35 or less is more preferable. From the viewpoint of improving curability, the ratio (molar ratio) of the benzocyclobutenyl group-containing group / (benzocyclobutenyl group-containing group + carbon-carbon unsaturated bond group-containing group) is 0.01 or more. Preferably, 0.05 or more is more preferable, and 0.08 or more is further preferable.

[Charge transport polymer]
Hereinafter, the first charge-transporting polymer and the second charge-transporting polymer will be described in detail.
(Benzocyclobutenyl group-containing group)
The benzocyclobutenyl group-containing group in the first charge-transporting polymer is a group containing one or more benzocyclobutenyl groups. The benzocyclobuteneyl group is a monovalent group derived from benzocyclobutene and has a structure capable of reacting with at least a carbon-carbon unsaturated bond group to form a bond. According to one embodiment, the benzocyclobutenyl group is a group having a structure capable of causing a Diels-Alder reaction, that is, a group that opens a ring and exhibits reactivity and can react with a carbon-carbon unsaturated bond group. be. For example, the benzocyclobutenyl group contains a group represented by the following formula (1). In the present disclosure, "*" in the formula represents a binding site with another structure.

R ^{a to} R ^g each independently represent a hydrogen atom or a substituent. R ^{a to} R ^g may be combined with each other to form a ring. Substituents are, for example, substituents selected from -R ¹ , -OR ² , -SR ³ , -OCOR ⁴ , -COOR ⁵ , -SiR ⁶ R ⁷ R ⁸ and halogen atoms (the substituents are selected from the halogen atoms. It may be referred to as "substituent ^RA").

In the present disclosure, R ^{1 to} R ⁸ independently represent a hydrogen atom; an alkyl group having 1 to 22 carbon atoms; or an aryl group or a heteroaryl group having 2 to 30 carbon atoms (where R ^1). Is a group selected from other than hydrogen atom.). The alkyl group may be further substituted with an aryl group having 2 to 20 carbon atoms or a heteroaryl group, and the aryl group or the heteroaryl group is further substituted with an alkyl group having 1 to 22 carbon atoms. You may.

In the present disclosure, the alkyl group may be a linear, branched or cyclic alkyl group. A linear, branched or cyclic alkyl group is an atomic group obtained by removing one hydrogen atom from a linear or branched saturated hydrocarbon, or an atomic group obtained by removing one hydrogen atom from a cyclic saturated hydrocarbon. Aryl groups are atomic groups obtained by removing one hydrogen atom from aromatic hydrocarbons. A heteroaryl group is an atomic group obtained by removing one hydrogen atom from an aromatic heterocycle. Examples of aromatic hydrocarbons and aromatic heterocycles are as given in the description of "aromatic rings" below.

In one embodiment, from the viewpoint of obtaining sufficient curability ^{, all of Ra to} R ^g are hydrogen atoms.

Further, in one embodiment, any one or more of ^{Ra to} R ^{g is an alkyl group.} The alkyl group may have 1 to 6 carbon atoms. Further, the alkyl group has any structure of a linear alkyl group (-C _n H _{2n + 1} ), a branched alkyl group (-C _n H _{2n + 1} ), and a cyclic alkyl group (-C _n H _2n-1 ). It may be (n is an integer of 1 or more, for example, an integer of 1 to 6).

A benzocyclobutenyl group-containing group is a group having a benzocyclobutenyl group. The first charge-transporting polymer may have only one type of benzocyclobutenyl group-containing group, or may have two or more types. The benzocyclobutenyl group-containing group may contain only one benzocyclobutenyl group or may contain two or more benzocyclobutenyl groups. When two or more are included, the two or more may be of the same type or different.

In one embodiment, the benzocyclobutenyl group-containing group may be the benzocyclobutenyl group itself. For example, the group represented by the formula (1) may be a benzocyclobutenyl group-containing group. In another embodiment, the benzocyclobutenyl group-containing group is a substituted or unsubstituted aromatic ring structure and benzocyclobutenyl attached to the aromatic ring structure directly or via a divalent linking group. It may be a group having a group. In the latter case, the benzocyclobutenyl group-containing group has a binding site with another structure on the aromatic ring structure. Examples of the divalent linking group include a substituted or unsubstituted alkylene group, an ether bond, a carbonyl bond, a substituted or unsubstituted aromatic ring group, or a group in which two or more selected from these are bonded. .. The aromatic ring structure, the alkylene group, and the substituents that the aromatic ring group may have are, for example, -R ¹ , -OR ² , -SR ³ , -OCOR ⁴ , -COOR ⁵ , -SiR ⁶ R ⁷ R ⁸ , halogen atom, and a substituent selected from the group consisting of benzocyclobutenyl group-containing group (the substituent may be referred to as "substituents R ^B".).

In the present disclosure, the alkylene group may be a linear, branched or cyclic alkylene group. The linear, branched or cyclic alkylene group is an atomic group obtained by removing two hydrogen atoms from a linear or branched saturated hydrocarbon, or an atomic group obtained by removing two hydrogen atoms from a cyclic saturated hydrocarbon.

In the present disclosure, the "aromatic ring" refers to a ring exhibiting aromaticity. The aromatic ring may be, for example, an aromatic hydrocarbon such as benzene, naphthalene, anthracene, tetracene, fluorene, or phenanthrene. Also, for example, pyridine, pyrazine, quinoline, isoquinolin, aclysine, phenanthroline, furan, pyrrole, thiophene, carbazole, oxazole, oxadiazole, thiadiazole, triazole, benzoxazole, benzoxadiazole, benzothiazole, benzotriazole, or benzo. It may be an aromatic heterocycle such as thiophene.

The aromatic ring may be a monocyclic ring such as benzene, a fused polycyclic aromatic hydrocarbon such as naphthalene, or a condensed polycyclic aromatic heterocycle such as quinoline.

The aromatic ring may have a structure in which two or more selected from independent monocyclic rings and fused rings are bonded, for example, biphenyl, terphenyl, and triphenylbenzene.

An example of a benzocyclobutenyl group-containing group is given below. The benzocyclobutenyl group-containing group is not limited to the following examples.

Ar represents a substituted or unsubstituted aromatic ring, X represents a divalent linking group, and ^{Ra to} R ^g independently represent a hydrogen atom or a substituent. l to m represent an integer, l is 0 or 1, n is 0 or 1, and m is 1 or more. The upper limit of m is determined according to the structure of Ar and the number of l.
Examples of substituents which may be possessed by the aromatic ring, the substituents R ^B, and examples of the substituent in the case where at least one of the substituents R ^a to R ^g, the substituents R ^A Can be mentioned.

An example of the group represented by the formula (4) is given below. The benzocyclobutenyl group-containing group is not limited to the following examples.

Ar represents a substituted or unsubstituted aromatic ring, and ^{Ra to} R ^g each independently represent a hydrogen atom or a substituent. l and m represent integers, l is 0 or 1, and m is 1 or more. The upper limit of m is determined according to the structure of Ar and the number of l. a to d represent an integer, a is 0 to 1, b is 0 to 20, c is 0 to 5, and d is 0 to 3.
Examples of substituents which may be possessed by the aromatic ring, the substituents R ^B, and examples of the substituent in the case where at least one of the substituents R ^a to R ^g, the substituents R ^A Can be mentioned.

An example of the group represented by the formula (5) is given below. The benzocyclobutenyl group-containing group is not limited to the following examples.

R ^{a to} R ^g each independently represent a hydrogen atom or a substituent.
An example of the substituent when at least one of R ^{a to} R ^{g is a substituent is the above-mentioned Substituent RA} .

An example of the group represented by the formula (5) is given below. The benzocyclobutenyl group-containing group is not limited to the following examples.

R ^{a to} R ^g each independently represent a hydrogen atom or a substituent. m is an integer of 1-5. a to d represent an integer, a is 0 to 1, b is 0 to 20, c is 0 to 5, and d is 0 to 3.
An example of the substituent when at least one of R ^{a to} R ^{g is a substituent is the above-mentioned Substituent RA} .

Specific examples of the benzocyclobutenyl group-containing group are shown below, but the present invention is not limited to the following specific examples.

(Carbon-carbon unsaturated bond group-containing group)
The carbon-carbon unsaturated bond group-containing group in the second charge-transporting polymer is a group containing one or more carbon-carbon unsaturated bond groups. The carbon-carbon unsaturated bond group has a structure capable of reacting with at least a benzocyclobutenyl group to form a bond. According to one embodiment, the carbon-carbon unsaturated bond group is a group having a structure capable of causing a Diels-Alder reaction. Examples of the carbon-carbon unsaturated bond group include a carbon-carbon double bond group and a carbon-carbon triple bond group, and a carbon-carbon double bond group is preferable, and a vinyl group is more preferable. Hereinafter, the carbon-carbon unsaturated bond group-containing group will be described by taking the case where the carbon-carbon unsaturated bond group is a vinyl group as an example. In the form in which the carbon-carbon unsaturated bond-containing group has a carbon-carbon unsaturated bond group other than the vinyl group, the "vinyl group" is replaced with the "carbon-carbon unsaturated bond group other than the vinyl group" as follows. The description can be applied. For example, the vinyl group is represented by the following formula (2).

R ^{a to} R ^c independently represent a hydrogen atom or a substituent. The substituent is, for example, the substituent ^RA .

In one embodiment, from the viewpoint of obtaining sufficient curability, Ra ^{a to} R ^c are, for example, all hydrogen atoms; ^Ra and R ^b are hydrogen atoms, and R ^c is a methyl group; ^Ra and R ^b. Is a hydrogen atom, R ^c is a phenyl group; or R ^a is a methyl group, and R ^b and R ^c are hydrogen atoms.

A vinyl group-containing group is a group having a vinyl group. The second charge-transporting polymer may have only one vinyl group-containing group, or may have two or more vinyl group-containing groups. The vinyl group-containing group may contain only one vinyl group or two or more vinyl groups. When two or more are included, the two or more may be of the same type or different.

In one embodiment, the vinyl group-containing group may be, for example, the vinyl group itself. For example, the group represented by the formula (2) may be a vinyl group-containing group. In another embodiment, the vinyl group-containing group is a group having a substituted or unsubstituted aromatic ring structure and a vinyl group attached to the aromatic ring structure directly or via a divalent linking group. There may be. In the latter case, the vinyl group-containing group has a binding site with another structure on the aromatic ring structure. Examples of the divalent linking group include a substituted or unsubstituted alkylene group, an ether bond, a carbonyl bond, a substituted or unsubstituted aromatic ring group, or a group in which two or more selected from these are bonded. .. The aromatic ring structure, the alkylene group, and the substituents that the aromatic ring group may have are, for example, -R ¹ , -OR ² , -SR ³ , -OCOR ⁴ , -COOR ⁵ , -SiR ⁶ R ⁷ R ⁸ , A substituent selected from the group consisting of a halogen atom and a vinyl group-containing group (the substituent may be referred to as "substituent ^RC ").

An example of a vinyl group-containing group is given below. The vinyl group-containing group is not limited to the following examples.

Ar represents a substituted or unsubstituted aromatic ring, X represents a divalent linking group, and ^{Ra to} R ^c independently represent a hydrogen atom or a substituent. l to m represent an integer, l is 0 or 1, n is 0 or 1, and m is 1 or more. The upper limit of m is determined according to the structure of Ar and the number of l.
An example of the substituent that the aromatic ring may have is the above-mentioned substituent ^{RC , and an example of the above-mentioned substituent when at least one of Ra to} R ^c is a substituent is the above-mentioned Substituent ^RA. Can be mentioned.

An example of the group represented by the formula (9) is given below. The vinyl group-containing group is not limited to the following examples.

Ar represents a substituted or unsubstituted aromatic ring, and ^{Ra to} R ^c independently represent a hydrogen atom or a substituent. l and m represent integers, l is 0 or 1, and m is 1 or more. The upper limit of m is determined according to the structure of Ar and the number of l. a to g represent integers, a is 0 to 20, b is 0 to 1, c is 0 to 20, d is 0 to 1, e is 0 to 1, f is 0 to 5, and g is 0 to 1. be.
An example of the substituent that the aromatic ring may have is the above-mentioned substituent ^{RC , and an example of the above-mentioned substituent when at least one of Ra to} R ^c is a substituent is the above-mentioned Substituent ^RA. Can be mentioned.

An example of the group represented by the formula (10) is given below. The vinyl group-containing group is not limited to the following examples.

R ^{a to} R ^c independently represent a hydrogen atom or a substituent.
As an example of the substituent when at least one of ^{R a to} R ^{c is a substituent, the above-mentioned Substituent RA} can be mentioned.

An example of the group represented by the formula (10) is given below. The vinyl group-containing group is not limited to the following examples.

R ^{a to} R ^c independently represent a hydrogen atom or a substituent. m is an integer of 1-5. a to g represent integers, a is 0 to 20, b is 0 to 1, c is 0 to 20, d is 0 to 1, e is 0 to 1, f is 0 to 5, and g is 0 to 1. be.
As an example of the substituent when at least one of ^{R a to} R ^{c is a substituent, the above-mentioned Substituent RA} can be mentioned.

Specific examples of the vinyl group-containing group are shown below, but the present invention is not limited to the following specific examples.

(Structure of charge transport polymer)
The term "charge-transporting polymer" described in the following description refers to a first charge-transporting polymer having a benzocyclobutenyl group-containing group and a second charge having a carbon-carbon unsaturated bond group-containing group. Means each of the transportable polymers. Further, the term "polymerizable functional group" refers to a benzocyclobutenyl group-containing group contained in the first charge-transporting polymer and a carbon-carbon unsaturated bond-containing group contained in the second charge-transporting polymer. Means each.

From the viewpoint of increasing the degree of freedom of the polymerizable functional group and facilitating the polymerization reaction, the main skeleton of the charge-transporting polymer and the polymerizable functional group are, for example, linear alkylene chains having 1 to 8 carbon atoms. It is preferable that they are connected, but the present invention is not particularly limited. Further, for example, when an organic layer is formed on an electrode, the main skeleton of the charge-transporting polymer and the polymerizable functional group are composed of an ethylene glycol chain from the viewpoint of improving the affinity with a hydrophilic electrode such as ITO. It is preferable that they are connected by a hydrophilic chain such as a diethylene glycol chain. Further, from the viewpoint of facilitating the preparation of the monomer used for introducing the polymerizable functional group, the charge transport polymer polymerizes with the terminal portion of the alkylene chain and / or the hydrophilic chain, that is, these chains. The linking portion with the sex functional group and / or the connecting portion between these chains and the skeleton of the charge-transporting polymer may have an ether bond or an ester bond.

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

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

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

The charge-transporting polymer may be linear or branched. The branched charge-transporting polymer has a structure branched in three or more directions. According to one embodiment, the charge-transporting polymer preferably contains at least a divalent structural unit L having charge-transporting properties and a structural unit T constituting the terminal portion, and has a trivalent or higher valence constituting the branched portion. Structural unit B may be further included. Further, according to one embodiment, the charge-transporting polymer preferably contains at least a trivalent structural unit B having a charge-transporting property and a monovalent structural unit T constituting a terminal portion, and has a divalent structure. The unit L may be further included. The charge-transporting polymer may contain only one type of each structural unit, or may contain a plurality of types of each structural unit. In the charge-transporting polymer, the structural units are bonded to each other at "monovalent" to "trivalent or higher" binding sites.

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

Examples of linear charge-transporting polymers

Examples of branched charge-transporting polymers

In the charge-transporting polymer, the polymerizable functional group is introduced into a portion other than the terminal portion (that is, the structural unit L or B) even if it is introduced into the terminal portion (that is, the structural unit T) of the charge-transporting polymer. Alternatively, it may be introduced in both the terminal portion and the non-terminal portion. From the viewpoint of curability, it is preferable that it is introduced at least at the terminal portion, and from the viewpoint of achieving both curability and charge transportability, it is preferable that it is introduced only at the terminal portion. Further, when the charge-transporting polymer is branched, the polymerizable functional group may be introduced into the main chain or the side chain of the charge-transporting polymer, and both the main chain and the side chain may be introduced. It may be introduced in. According to one embodiment, from the viewpoint of reactivity between the charge-transporting polymers, at least one of the first charge-transporting polymer and the second charge-transporting polymer has at least one polymerizable functional group at the terminal. Is preferable. Further, according to one embodiment, at least one of the benzocyclobutenyl group-containing groups is present at the terminal of the first charge-transporting polymer, and at least one of the carbon-carbon unsaturated bond-containing groups is the second. It is preferably present at the end of the charge transport polymer of. Hereinafter, each structural unit will be specifically described.

(Structural unit L)
The structural unit L is a divalent structural unit having charge transportability. The structural unit L is not particularly limited as long as it includes an atomic group capable of transporting electric charges. For example, the structural unit L is a substituted or unsubstituted aromatic amine structure, carbazole structure, thiophene structure, bithiophene structure, fluorene structure, benbenzocyclobutene structure, biphenyl structure, terphenyl structure, naphthalene structure, anthracene structure, tetracene. Structure, phenanthracene structure, dihydrophenanthracene structure, pyridine structure, pyrazine structure, quinoline structure, isoquinoline structure, quinoxalin structure, acrydin structure, diazaphenanthracene structure, furan structure, pyrrol structure, oxazole structure, oxazole structure, thiazole structure, thiazole It is selected from a structure, a triazole structure, a benzothiophene structure, a benzoxazole structure, a benzoxazole structure, a benzothiazole structure, a benzothiazole structure, a benzotriazole structure, and a structure containing one or more of these. The aromatic amine structure is preferably a triarylamine structure, more preferably a triphenylamine structure. The benzocyclobutene structure is preferably a p-phenylene structure or an m-phenylene structure.

In one embodiment, the structural unit L is a substituted or unsubstituted aromatic amine structure, carbazole structure, thiophene structure, bithiophene structure, fluorene structure, benbenzocyclobutene structure, from the viewpoint of obtaining excellent hole transportability. And preferably having one or more structures selected from the pyrrole structure, more preferably having one or more structures selected from substituted or unsubstituted aromatic amine structures, carbazole structures, thiophene structures, and fluorene structures. It is preferable to have one or more structures selected from a substituted or unsubstituted aromatic amine structure and a carbazole structure.

In another embodiment, the structural unit L is selected from substituted or unsubstituted fluorene structure, benzocyclobutene structure, phenanthrene structure, pyridine structure, and quinoline structure from the viewpoint of obtaining excellent electron transportability. It is preferable to have the above structure.

The specific structure of the structural unit L is not particularly limited, and examples thereof include the structure described in paragraph 0097 of International Publication No. 2010/1405553.

(Structural unit T)
The structural unit T is a structural unit that constitutes the terminal portion of the charge-transporting polymer. The structural unit T is not particularly limited, and is selected from, for example, a substituted or unsubstituted aromatic hydrocarbon structure, an aromatic heterocyclic structure, and a structure containing one or more of these. In one embodiment, the structural unit T is preferably a substituted or unsubstituted aromatic hydrocarbon structure from the viewpoint of imparting durability without reducing charge transportability. With respect to other than the valence, the structural unit T may have the same structure as at least one of the structural units L and B, or may have a different structure.

In a preferred embodiment, the structural unit T preferably comprises a structural unit having a polymerizable functional group. For example, the first charge-transporting polymer has a structural unit T1 having a benzocyclobutenyl group-containing group. The second charge-transporting polymer also has a structural unit T2 having a carbon-carbon unsaturated bond-containing group. Each of the first charge-transporting polymer and the second charge-transporting polymer may further have a structural unit T3 that does not have a benzocyclobutenyl group-containing group and a carbon-carbon unsaturated bond group-containing group. ..

The structural unit T1 can be represented by the following equation (3).

T1 is a structure containing a benzocyclobutenyl group-containing group. The benzocyclobutenyl group-containing group described above may be T1, and as an example of T1, the group represented by the formula (4), the group represented by the formula (5), and the table represented by the formula (6). Examples thereof include a group to be used and a group represented by the formula (7).

The structural unit T2 can be represented by the following equation (8).

T2 is a structure containing a carbon-carbon unsaturated bond group-containing group. The carbon-carbon unsaturated bond group-containing group described above may be T2, and examples of T2 include a group represented by the formula (9), a group represented by the formula (10), and a formula (11). Examples thereof include a group represented by and a group represented by the formula (12).

Specific examples of the structural unit T3 include the following. However, the structural unit T3 is not limited to the following.

R is independently a hydrogen atom or a substituent, and the substituent is, for example, a substituent ^RA .

(Structural unit B)
The structural unit B is a trivalent or higher structural unit constituting the branched portion when the charge-transporting polymer or oligomer has a structure branched in three or more directions. The structural unit B is preferably hexavalent or less, and more preferably trivalent or tetravalent, from the viewpoint of improving the durability of the organic electronic device. The structural unit B is preferably a unit having charge transportability. For example, the structural unit B is a substituted or unsubstituted aromatic amine structure, carbazole structure, condensed polycyclic aromatic hydrocarbon structure, and one or two of these, from the viewpoint of improving the durability of the organic electronic device. Selected from structures containing more than a species. With respect to other than the valence, the structural unit B may have the same structure as the structural unit L, or may have a different structure, or may have the same structure as the structural unit T. Alternatively, it may have a different structure.

The specific structure of the structural unit B is not particularly limited, and examples thereof include the structure described in paragraph 0091 of International Publication No. 2010/1405553.

(Number average molecular weight)
The number average molecular weight of the charge-transporting polymer can be appropriately adjusted in consideration of solubility in a solvent, film-forming property, and the like. The number average molecular weight is preferably 500 or more, more preferably 1,000 or more, and even more preferably 2,000 or more, from the viewpoint of excellent charge transportability. Further, in one embodiment, the number average molecular weight is preferably 18,000 or more, more preferably 20,000 or more, and even more preferably 25,000 or more. On the other hand, the number average molecular weight is preferably 1,000,000 or less, more preferably 100,000 or less, and 60, from the viewpoint of maintaining good solubility in the solvent and facilitating the preparation of the ink composition. More preferably, it is 000 or less.

(Weight average molecular weight)
The weight average molecular weight of the charge-transporting polymer can be appropriately adjusted in consideration of solubility in a solvent, film-forming property, and the like. The weight average molecular weight is preferably 1,000 or more, more preferably 5,000 or more, still more preferably 10,000 or more, from the viewpoint of excellent charge transportability. On the other hand, the weight average molecular weight is preferably 1,000,000 or less, more preferably 700,000 or less, and more preferably 400, from the viewpoint of maintaining good solubility in the solvent and facilitating the preparation of the ink composition. It is more preferably 000 or less, and particularly preferably 300,000 or less. Further, in one embodiment, the weight average molecular weight of the charge transport polymer is preferably 200,000 or less.

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

The number average molecular weight and the weight average molecular weight can be measured by gel permeation chromatography (GPC) under the following conditions using a standard polystyrene calibration curve.
Liquid transfer pump: L-6050 Hitachi High-Technologies Corporation UV-Vis detector: L-3000 Hitachi High-Technologies Corporation Column: Gelpack (registered trademark) GL-A160S / GL-A150S Hitachi Kasei Co., Ltd. Eluent: THF (HPLC) Wako Pure Chemical Industries, Ltd. Flow velocity: 1 mL / min
Column temperature: Room temperature Molecular weight standard substance: Standard polystyrene

(Ratio of structural units)
When the charge transporting polymer contains the 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 the structural units, from the viewpoint of obtaining sufficient charge transportability. , 30 mol% or more is more preferable. Further, the ratio of the structural unit L is preferably 95 mol% or less, more preferably 90 mol% or less, still more preferably 85 mol% or less, considering the structural unit T and the structural unit B to be introduced as needed.

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

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

The proportion of the polymerizable functional group is preferably 0.1 mol% or more, more preferably 0.5 mol% or more, and 1 mol% based on the total structural units, from the viewpoint of efficiently curing the charge-transporting polymer. The above is more preferable. The proportion of the polymerizable functional group is preferably 30 mol% or less, more preferably 20 mol% or less, further preferably 10 mol% or less, and particularly preferably 5 mol% or less, from the viewpoint of obtaining good charge transportability. It is preferably 2.5 mol% or less, which is extremely preferable. The "ratio of polymerizable functional groups" here means the ratio of structural units having polymerizable functional groups. By using the first charge-transporting polymer and the second charge-transporting polymer in combination, sufficient insolubilization is achieved even when the proportion of polymerizable functional groups contained in each charge-transporting polymer is small. can.

When the charge-transporting polymer has a polymerizable functional group at the terminal, the proportion of the structural unit having the polymerizable functional group (structural unit T1 or structural unit T2) is all from the viewpoint of efficiently curing the charge-transporting polymer. Based on the terminal structural unit T, 1 mol% or more is preferable, 1.5 mol% or more is more preferable, and 2 mol% or more is further preferable. The ratio of the structural unit having a polymerizable functional group (structural unit T1 or structural unit T2) is preferably 30 mol% or less, more preferably 20 mol% or less, from the viewpoint of obtaining good charge transportability. More preferably, it is mol% or less.

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

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

(Degree of polymerization)
The degree of polymerization (number of units 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. The degree of polymerization is preferably 1,000 or less, more preferably 700 or less, and even more preferably 500 or less, from the viewpoint of solubility in a solvent.

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

In a preferred embodiment, the charge transport polymer comprises a substituted or unsubstituted aromatic amine structure, carbazole structure, thiophene structure, and fluorene structure from the viewpoint of having high hole injectability, hole transport property, and the like. It preferably has one or more structures selected from the group. Further, in a particularly preferable embodiment, the charge transporting polymer mainly contains a structural unit having an aromatic amine structure and / or a structural unit having a carbazole structure from the viewpoint of having high hole injection property, hole transport property and the like. It is preferable that the compound has a structural unit (main skeleton). For example, the ratio of the structural unit having an aromatic amine structure and the structural unit having a carbazole structure is preferably 50 mol% or more, more preferably 70 mol% or more, still more preferably 90 mol% or more. The upper limit is 100 mol%. The ratio here is the total structural unit of the structural unit L and the structural unit B (if the charge-transporting polymer contains only one of them, the structural unit of the other. If the polymer contains both, the total structural unit of both. ) Is the total ratio of the structural unit having an aromatic amine structure and the structural unit having a carbazole structure contained in the structural unit L and the structural unit B.

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

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

[Dopant]
The charge-transporting material may contain any additive, for example, may further contain a dopant, for example, the dopant may be added to the charge-transporting material to exhibit a doping effect and improve charge transportability. There is no particular limitation as long as it is obtained. Doping includes p-type doping and n-type doping. In p-type doping, a substance that acts as an electron acceptor as a dopant is used, and in n-type doping, a substance that acts as an electron donor as a dopant is used. P-type doping is preferable for improving hole transportability, and n-type doping is preferable for improving electron transportability. The dopant used in the charge transport material may be a dopant that exhibits either the p-type doping or the n-type doping effect. Further, one kind of dopant may be added alone, or a plurality of kinds of dopants may be mixed and added.

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

The dopant used for n-type doping is an electron-donating compound, for example, an alkali metal such as Li and Cs, an alkaline earth metal such as Mg and Ca, an alkali metal such as LiF and Cs ₂ CO ₃ , and /. Alternatively, alkali earth metal salts, metal complexes, electron-donating organic compounds and the like can be mentioned.

In the dopant, the ionic compound also functions as a polymerization initiator. A charge-transporting material containing a first charge-transporting polymer and a second charge-transporting polymer can be insolubilized without the use of a polymerization initiator, but if desired, a charge-transporting material. Ionic compounds may be included with the intent of improvement.

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

[Content]
The total content of the first charge transport polymer and the second charge transport polymer in the charge transport material is 50 mass with respect to the total mass of the charge transport material from the viewpoint of obtaining good charge transport. % Or more, more preferably 70% by mass or more, and even more preferably 80% by mass or more. The upper limit of the total content of the first charge-transporting polymer and the second charge-transporting polymer is not particularly limited, and may be 100% by mass. The content of the charge-transporting polymer may be, for example, 95% by mass or less, 90% by mass or less, etc. in consideration of containing an additive such as a dopant.

When the dopant is contained, the content thereof is preferably 0.01% by mass or more, preferably 0.1% by mass, based on the total mass of the charge-transporting material from the viewpoint of improving the charge-transporting property of the charge-transporting material. The above is more preferable, and 0.5% by mass or more is further preferable. On the other hand, from the viewpoint of preventing roughness of the film surface, uneven film thickness, and the like, the content of the dopant is preferably 40% by mass or less, more preferably 30% by mass or less, and further preferably 20% by mass or less.

<Ink composition>
In 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, the organic layer can be easily formed by a simple method such as a coating method.

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

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

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

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

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

The charge-transporting material or the ink composition used to form the organic layer has a first charge-transporting polymer having a benzocyclobutenyl group-containing group and a carbon-carbon unsaturated bond-containing group. Includes a second charge transport polymer. Therefore, the Diels-Alder reaction between the first charge-transporting polymer and the second charge-transporting polymer proceeds by performing the heat treatment after the application of the charge-transporting material or the ink composition, and as compared with the conventional case, The organic layer can be sufficiently insolubilized (cured). For example, after applying a charge transporting material or an ink composition, the organic layer can be sufficiently cured by heating at 120 ° C. or higher. In one embodiment, the heating temperature at the time of curing is preferably 160 ° C. or higher, more preferably 180 ° C. or higher. It is also possible to heat at a higher temperature, for example, 200 ° C. or higher is preferable, 215 ° C. or higher is more preferable, and 230 ° C. or higher is even more preferable. Further, the heating temperature is preferably 350 ° C. or lower, more preferably 250 ° C. or lower, still more preferably 200 ° C. or lower, in consideration of the influence of heating on the organic layer, the substrate and the like. The heating time is not particularly limited, but is preferably adjusted within 60 minutes, more preferably within 30 minutes, from the viewpoint of suppressing deterioration of the performance of the organic layer due to heating.

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

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

<Organic EL element>
In one embodiment, the organic EL device has at least one or more of the organic layers. The organic EL element usually includes a light emitting layer, an anode, a cathode, and a substrate, and if necessary, provides other functional layers such as a hole injection layer, an electron injection layer, a hole transport layer, and an electron transport layer. I have. Each layer may be formed by a thin-film deposition method or a coating method. The organic EL device preferably has the organic layer as a light emitting layer or a functional layer, more preferably as a functional layer, and further preferably as at least one of a hole injection layer and a hole transport layer.

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

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

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

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

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

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

[Hole injection layer, hole transport layer]
In FIG. 1, at least one of the hole injection layer 3 and the hole transport layer 6 may be an organic layer formed by using the charge transporting material or the ink composition, and the organic EL element is thus described. It is not limited to a simple structure. An organic layer other than the hole injection layer and the hole transport layer may be formed by using the charge transport material.

The charge transporting material is preferably used as a hole injecting material and / or a hole transporting material. For example, the charge transporting material is preferably used as a material constituting at least one of a hole injecting layer and a hole transporting layer, and more preferably used as a material for at least a hole transporting layer. As described above, these layers can be easily formed by using an ink composition containing a charge transporting material.

For example, when the organic EL device has an organic layer formed by using the charge transporting 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 by 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. ..

Materials that can be used for the hole injection layer and the hole transport layer include aromatic amine compounds (N, N'-di (naphthalene-1-yl) -N, N'-diphenyl-benzidine (α-NPD). ) And other aromatic diamines), phthalocyanine compounds, thiophene compounds and the like.

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

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

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

[substrate]
As the substrate, a glass substrate, a resin substrate, or the like can be used, and a resin substrate is preferably used. The substrate is preferably transparent, and is preferably a flexible substrate having flexibility. Quartz glass, a light-transmitting resin film and the like are preferably used.

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

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

[Sealing]
The organic EL element may be sealed in order to reduce the influence of the outside air and prolong the life. As the material used for sealing, a plastic film such as glass, epoxy resin, acrylic resin, polyethylene terephthalate or polyethylene naphthalate, or an inorganic substance such as silicon oxide or silicon nitride can be used, but the material is not limited thereto. No. The sealing method is also not particularly limited, and a known method can be used.

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

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

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

Further, in one embodiment, the lighting device includes the organic EL element.
Further, in one embodiment, the display device includes the lighting device and a liquid crystal element as a display means. For example, the display device can be a display device using the lighting device as a backlight and a known liquid crystal element as a display means, that is, a liquid crystal display device.

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

<Example of monomer synthesis>
Examples of monomer synthesis are shown below, but the present invention is not limited to the following synthesis examples.

(Synthesis Example 1)
Monomer T1-2 having the following structure was synthesized by the following method. Specifically, it was synthesized by the following route.

In a nitrogen atmosphere, 5-bromo-1-pentene (7.45 g, 50 mmol) and tetrahydrofuran (20 mL) were mixed in a 300 mL three-necked flask to obtain a solution. A 0.5 M 9-BBN / THF solution (9-borabicyclo [3.3.1] nonane tetrahydrofuran solution) (100 mL) was added dropwise to the obtained solution over 1 hour, and the mixture was stirred at room temperature for 12 hours. Monomer T1-1 (3.66 g, 20 mmol), (diphenylphosphinoferrocene) palladium dichloride (0.82 g), tetrahydrofuran (32 mL), and 3M aqueous sodium hydroxide solution (27 mL) were added to the obtained reaction solution. Was mixed and refluxed for 4 hours. After completion of the reaction, the obtained solution was cooled to room temperature, hexane (40 mL) was added, hydrogen peroxide solution (6 mL) was slowly added dropwise while ice-cooling, and the mixture was stirred for 1 hour. After separating the reaction solution, the organic layer was washed 5 times with ion-exchanged water (50 mL). The obtained organic layer was dried over sodium sulfate, and then purified by column chromatography using hexane as a developing solvent and silica gel as a filler to obtain Intermediate A (3.80 g, 15 mmol).

Intermediate A (3.80 g, 15 mmol), 4-bromophenol (3.89 g, 22.5 mmol), tetrabutylammonium bromide (0.16 g, 0.5 mmol) in a 50 mL two-necked flask under a nitrogen atmosphere. , 50% aqueous potassium hydroxide solution (6.7 g), and toluene (20 mL) were mixed and refluxed for 6 hours. After completion of the reaction, the obtained solution was washed 3 times with ion-exchanged water (10 mL). The obtained organic layer is dried with sodium sulfate, and then purified by column chromatography using a mixed solvent of hexane / ethyl acetate (95/5) as a developing solvent and silica gel as a filler, thereby purifying the monomer T1-2. Was obtained (4.14 g, 12 mmol).

(Synthesis Example 2)
Monomer T2-4 having the following structure was synthesized by the following method. Specifically, it was synthesized by the following route.

Magnesium (0.53 g, 22 mmol) and tetrahydrofuran (10 mL) were charged into a 100 mL three-necked flask under a nitrogen atmosphere. 8-Bromo-1-octene (3.82 g, 20 mmol) dissolved in tetrahydrofuran (20 mL) was added dropwise over 20 minutes. 4-Bromobenzyl bromide (5.50 g, 22 mmol) was added to the obtained solution, and the mixture was stirred at room temperature for 1 hour and then heated to reflux for 3 hours. The resulting reaction solution was washed 3 times with ion-exchanged water (10 mL). After drying over sodium sulfate, sodium sulfate was filtered and the solvent was distilled off. Purification by column chromatography gave the monomer T2-4 (2.81 g, 10 mmol).

<Synthesis example of charge transport polymer>
(Preparation of Pd catalyst)
Tris (dibenzylideneacetone) dipalladium (73.2 mg, 80 μmol) was weighed in a sample tube at room temperature in a glove box under a nitrogen atmosphere, anisole (15 mL) was added, and the mixture was stirred for 30 minutes. Similarly, tris (t-butyl) phosphine (129.6 mg, 640 μmol) was weighed into a sample tube, anisole (5 mL) was added, and the mixture was stirred for 5 minutes. These solutions were mixed and stirred at room temperature for 30 minutes to catalyze. All solvents were used after degassing with nitrogen bubbles for at least 30 minutes.

(Synthesis of Charge Transport Polymer A)
In a three-necked round-bottom flask, the following monomer L1 (10.0 mmol), the following monomer B1 (5.0 mmol), the following monomer T1-2 (0.125 mmol), the following monomer T3 (4.875 mmol), and toluene (42.8 mL) , And methyltri-n-octylammonium chloride (67.2 mg) were added, and the prepared Pd catalyst solution (15.0 mL) was further added. After stirring for 30 minutes, a 3M aqueous potassium hydroxide solution (13.5 mL) was added. All solvents were used after degassing with nitrogen bubbles for at least 30 minutes. The mixture was heated to reflux for 2 hours. All operations up to this point were performed under a nitrogen stream.

After completion of the reaction, the organic layer was washed with water, and the organic layer was poured into methanol-water (9: 1). The generated precipitate was collected by suction filtration and washed with butyl acetate to obtain a precipitate. The obtained precipitate was collected by suction filtration, dissolved in toluene, and a metal adsorbent (“Triphenylphosphine, polymer-bound on styrene-divinylbenzene copolymer” manufactured by Stream Chemicals, 200 mg with respect to 100 mg of the precipitate) was added. It was stirred in the evening. After the stirring was completed, the metal adsorbent and the insoluble matter were filtered off, and the filtrate was concentrated with a rotary evaporator. The concentrate was dissolved in toluene and then reprecipitated from methanol-acetone (8: 3). The resulting precipitate was collected by suction filtration and washed with methanol-acetone (8: 3). The obtained precipitate was vacuum dried to obtain a charge-transporting polymer A.

The obtained charge-transporting polymer A had a number average molecular weight of 30,799 and a weight average molecular weight of 97,707. The charge transporting polymer A has a structural unit L1, a structural unit B1, a structural unit T1-2, and a structural unit T-3, and the ratio (molar ratio) of each structural unit is 50.0%, 25. It was 0%, 0.63%, and 24.38%.

(Synthesis of Charge Transport Polymer B)
In a three-necked round-bottom flask, the monomer L1 (10.0 mmol), the monomer B1 (5.0 mmol), the following monomer T2-4 (0.125 mmol), the monomer T3 (4.875 mmol), and toluene (42.8 mL). , And methyltri-n-octylammonium chloride (67.2 mg) were added, and the prepared Pd catalyst solution (15.0 mL) was further added. Subsequently, the charge-transporting polymer B was obtained in the same manner as in the synthesis of the charge-transporting polymer A.

The obtained charge-transporting polymer B had a number average molecular weight of 29,012 and a weight average molecular weight of 91,952. The charge transporting polymer B has a structural unit L1, a structural unit B1, a structural unit T2-4, and a structural unit T3, and the ratio (molar ratio) of each structural unit is 50.0% and 25.0%. , 0.63%, and 24.38%.

(Synthesis of Charge Transport Polymer C)
In a three-necked round-bottom flask, the monomer L1 (10.0 mmol), the monomer B1 (5.0 mmol), the monomer T1-2 (0.25 mmol), the monomer T3 (4.75 mmol), and toluene (42.7 mL). ), Methyltri-n-octylammonium chloride (67.2 mg) was added, and the prepared Pd catalyst solution (15.0 mL) was further added. Subsequently, a charge-transporting polymer C was obtained in the same manner as in the synthesis of the charge-transporting polymer A.

The obtained charge-transporting polymer C had a number average molecular weight of 56,144 and a weight average molecular weight of 112,751. The charge transporting polymer C has a structural unit L1, a structural unit B1, a structural unit T1-2, and a structural unit T3, and the ratio (molar ratio) of each structural unit is 50.0% and 25.0%. , 1.25%, and 23.75%.

(Synthesis of Charge Transport Polymer D)
In a three-necked round-bottom flask, the monomer L1 (10.0 mmol), the monomer B1 (5.0 mmol), the monomer T2-4 (0.25 mmol), the monomer T3 (4.75 mmol), and toluene (80.1 mL). ), Methyltri-n-octylammonium chloride (67.2 mg) was added, and the prepared Pd catalyst solution (15.0 mL) was further added. Subsequently, a charge-transporting polymer D was obtained in the same manner as in the synthesis of the charge-transporting polymer A.

The obtained charge-transporting polymer D had a number average molecular weight of 55,718 and a weight average molecular weight of 112,656. The charge transporting polymer 4 has a structural unit L1, a structural unit B1, a structural unit T2-4, and a structural unit T3, and the ratio (molar ratio) of each structural unit is 25.0% and 50.0%. , 1.25%, and 23.75%.

<Evaluation of solvent resistance>
An ink composition containing the charge-transporting polymer A and the charge-transporting polymer B, and an ink composition containing the charge-transporting polymer C and the charge-transporting polymer D are used so that the film thickness is 60 to 80 nm. An organic layer was formed. The solvent resistance (insolubilization effect) of the organic layer was evaluated by determining the effect of improving the residual film ratio by blending.

[Comparative Example 1]
The charge-transporting polymer A (10.0 mg) was dissolved in toluene (2,000 μL) to obtain a coating solution (ink composition). The coating solution was spin coated onto a quartz substrate at 3,000 rpm. The quartz substrate was then heated at 220 ° C. for 30 minutes on a hot plate to polymerize the charge transport polymer A to form an organic layer. Then, a quartz substrate having an organic layer formed on its surface was immersed in toluene (25 ° C.) for 1 minute. The residual film ratio was measured from the ratio of the absorption maximum (λmax) to the absorbance (Abs) in the UV-vis spectrum of the organic layer before and after immersion, and was found to be 74.7%. The UV-vis spectrum was measured using a spectrophotometer (“U-3900H” manufactured by Hitachi High-Technologies Corporation) with a wavelength range of 300 to 500 nm.

[Comparative Example 2]
A polymer layer was formed in the same manner as in Comparative Example 1 except that the charge-transporting polymer B (10.0 mg) was used instead of the charge-transporting polymer A, and the residual film ratio was measured. The residual film ratio was 40.2%.

[Example 1]
The charge-transporting polymer A (1.0 mg) and the charge-transporting polymer B (9.0 mg) were dissolved in toluene (2,000 μL) to obtain a coating solution (ink composition). The coating solution was spin coated onto a quartz substrate at 3,000 rpm. Next, the quartz substrate was heated at 220 ° C. for 30 minutes on a hot plate to polymerize the charge-transporting polymer A and the charge-transporting polymer B to form an organic layer. When the effect of blending the organic layer was evaluated by the following method, it was 21.8%.

(1) The "residual film ratio (%) contributed by the charge-transporting polymer A" is set to the residual film ratio of the organic layer formed by using the solution containing only the charge-transporting polymer A, and the charge in the coating solution. It was calculated as a value obtained by multiplying the total mass of the transportable polymer A and the charge transport polymer B by the ratio of the mass of the charge transport polymer A.

(2) In the same manner as in (1) above, the "residual film ratio (%) contributed by the charge-transporting polymer B" was determined. That is, the residual film ratio contributed by the charge-transporting polymer (B) was calculated by the same method as in (1) above except that the charge-transporting polymer A was replaced with the charge-transporting polymer B.

(3) The "expected residual film ratio (%)" was calculated by adding the residual film ratio contributed by the charge-transporting polymer A and the residual film ratio contributed by the charge-transporting polymer B. When the coating solution is prepared by blending the charge-transporting polymer A and the charge-transporting polymer B, the charge-transporting polymer A and the charge-transporting polymer B do not interact with each other when the coating solution is heated and cured. If so, the residual film ratio of the organic layer after curing is considered to be a value obtained by adding the residual film ratio contributed by the charge-transporting polymer A and the residual film ratio contributed by the charge-transporting polymer B.

(4) The "effect (%) due to compounding" was calculated by taking the difference between the measured residual film ratio and the assumed residual film ratio.

[Examples 2 to 5]
An organic layer was formed in the same manner as in Example 1 except that the charge-transporting polymers A and B were used so that the total amount was 10.0 mg at the compounding ratio shown in Table 1, and the effect of the compounding was evaluated. ..

[Comparative Example 3]
An organic layer was formed in the same manner as in Comparative Example 1 except that the charge-transporting polymer C (10.0 mg) was used instead of the charge-transporting polymer A, and the residual film ratio was measured. The residual film ratio was 87.6%.

[Comparative Example 4]
An organic layer was formed in the same manner as in Comparative Example 1 except that the charge-transporting polymer D (10.0 mg) was used instead of the charge-transporting polymer A, and the residual film ratio was measured. The residual film ratio was 72.8%.

[Examples 6 to 10]
An organic layer was formed in the same manner as in Example 1 except that the charge-transporting polymers C and D were used in the blending ratios shown in Table 2 so that the total amount was 10.0 mg, and the residual film ratio was improved. The effect was evaluated.

The evaluation results of the effect of the combination are shown in Tables 1 and 2 below.

The effect of blending was obtained for all the organic layers of Examples 1 to 5 and Examples 6 to 10. From this, it can be seen that the solvent resistance of the organic layer can be enhanced by using the charge transporting material containing the first charge transporting polymer and the second charge transporting polymer.

<Evaluation of fluorescence spectrum>
The change in the fluorescence spectrum due to curing was evaluated for the organic layer formed by using the ink composition containing the charge-transporting polymer C and the charge-transporting polymer D.

[Reference Examples 1 to 7]
An organic layer was formed in the same manner as in Examples 6 to 10 and Comparative Examples 3 and 4 except that the mixture was allowed to stand in the atmosphere at room temperature of 25 ° C. for 60 minutes without heating, and the fluorescence spectrum was measured. The fluorescence spectrum was measured using a spectrofluorometer (“F-7000” manufactured by Hitachi High-Technologies Corporation) under the conditions of excitation light of 380 nm and a wavelength range of 400 to 600 nm.

FIG. 2 shows a fluorescence spectrum, and FIG. 3 shows a difference spectrum between the fluorescence spectrum measured in Reference Example 1 and the fluorescence spectrum measured in Reference Example 5. Even if the blending ratio of the charge-transporting polymer C and the charge-transporting polymer D was changed, there was almost no change in the fluorescence spectrum.

[Examples 11 to 15 and Comparative Examples 5 and 6]
An organic layer was formed in the same manner as in Examples 6 to 10 and Comparative Examples 3 and 4 except that heating was carried out at 230 ° C. for 60 minutes in a nitrogen atmosphere, and the fluorescence spectrum was measured in the same manner as in Reference Example. bottom.

FIG. 4 shows a fluorescence spectrum, and FIG. 5 shows a difference spectrum between the fluorescence spectrum measured in Example 11 and the fluorescence spectrum measured in Example 15. The fluorescence spectrum changed depending on the blending ratio of the charge-transporting polymer C and the charge-transporting polymer D. From the difference spectrum between the fluorescence spectrum measured in Example 11 and the fluorescence spectrum measured in Example 15, a change having a peak at 476 nm was confirmed.

Table 3 shows the spectral intensities of each organic layer at 475 nm, and further shows the difference between the spectral intensities and the spectral intensities of the organic layers obtained in Reference Examples 1 to 7 at 475 nm.

The results showed that the higher the blending ratio of the charge-transporting polymer D, the smaller the change in the fluorescence spectrum. From this, it can be seen that the change in the fluorescence spectrum can be controlled by adjusting the content of the benzocyclobutenyl group-containing group and the carbon-carbon unsaturated bond group-containing group in the charge transporting material.

The effects of the embodiments of the present invention have been shown above using examples. In addition to the charge-transporting polymer used in the examples, the first charge-transporting polymer having a benzocyclobutenyl group-containing group and the second having a carbon-carbon unsaturated bond group-containing group described above A charge-transporting material containing a charge-transporting polymer can exhibit a higher insolubilizing effect than using any of the charge-transporting polymers alone.

According to one embodiment, the charge-transporting material containing the first charge-transporting polymer and the second charge-transporting polymer is a material suitable for a wet process, and the formation of an organic layer using the wet process. Can be preferably used for. Further, according to one embodiment, the organic layer formed by using the charge transporting material is a layer suitable for a lower layer having a multi-layer structure, and can be preferably used for manufacturing an organic electronic device having a multi-layer structure.

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

Claims (15)

Possess one or more benzocyclobutenyl group-containing group, the proportion of the structural unit having an benzocyclobutenyl group-containing group is, Ru der 0.1 mol% to 5 mol% of the total structural units as Standards 1 charge transport polymer and
It has a carbon unsaturated bond group-containing group, the carbon - - 1 or more carbon ratio of the structural units having a carbon-carbon unsaturated bond group-containing group is, 0.1 mol% to 5 mol% of the total structural units based second charge transport polymer Ru der,
Contains ,
Benzocyclobutenyl group-containing group / - molar ratio (benzocyclobutenyl group-containing group + carbon-carbon unsaturated bond group-containing group) is either less than 0.8 or, Ru der 0.35,
Charge transport material. The charge-transporting material according to claim 1, wherein the first charge-transporting polymer and the second charge-transporting polymer each have a structure branched in three or more directions. One or more selected from the group consisting of a substituted or unsubstituted aromatic amine structure, a carbazole structure, a thiophene structure, and a fluorene structure, respectively, of the first charge transport polymer and the second charge transport polymer. The charge transporting material according to claim 1 or 2, which has a structure. At least one of the one or more benzocyclobutenyl group-containing groups is present at the terminal of the first charge-transporting polymer, and at least one of the one or more carbon-carbon unsaturated bond-containing groups is said to be the first. The charge-transporting material according to any one of claims 1 to 3, which is present at the end of the charge-transporting polymer of 2. Claims 1 to 1, wherein the benzocyclobutenyl group-containing group contains a group represented by the following formula (4).
The charge transporting material according to any one of 4.

(Ar represents a substituted or unsubstituted aromatic ring, X represents a divalent linking group, and ^{Ra to} R ^g are
Each independently represents a hydrogen atom or a substituent. l to m represent an integer, l is 0 or 1, n is 0 or 1, and m is 1 or more. ) Claims 1 to 1, wherein the carbon-carbon unsaturated bond group-containing group contains a group represented by the following formula (9).
5. The charge transporting material according to any one of 5.

(Ar represents a substituted or unsubstituted aromatic ring, X represents a divalent linking group, and Ra ^{a to} R ^c are
Each independently represents a hydrogen atom or a substituent. l to m represent an integer, l is 0 or 1, n is 0 or 1, and m is 1 or more. ) The charge transporting material according to any one of claims 1 to 6, which is a hole injecting material or a hole transporting material. An ink composition comprising the charge transporting material according to any one of claims 1 to 7 and a solvent. An organic electronic device having an organic layer formed by using the charge transporting material according to any one of claims 1 to 7 or the ink composition according to claim 8. An organic electroluminescence device having an organic layer formed by using the charge transporting material according to any one of claims 1 to 7 or the ink composition according to claim 8. The organic electroluminescence device according to claim 10, further comprising a flexible substrate. The organic electroluminescence device according to claim 10, further comprising a resin substrate. The organic electroluminescence element according to any one of claims 10 to 12 is provided.
Display element. The organic electroluminescence element according to any one of claims 10 to 12 is provided.
Lighting device. A display device including the lighting device according to claim 14 and a liquid crystal element as a display means.

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