WO2019175979A1

WO2019175979A1 - Organic electronic material and organic electronic element

Info

Publication number: WO2019175979A1
Application number: PCT/JP2018/009777
Authority: WO
Inventors: 涼本名; 伊織福島; 広貴佐久間
Original assignee: 日立化成株式会社
Priority date: 2018-03-13
Filing date: 2018-03-13
Publication date: 2019-09-19
Also published as: JPWO2019175979A1; JP7131606B2; TW201938762A

Abstract

The present invention relates to an organic electronic material which contains a charge transporting polymer or oligomer having a structural unit that has a branch structure and that has the partial structure represented in formula (1).

Description

Organic electronics materials and organic electronics elements

Embodiments of the present invention relate to an organic electronics material, an ink composition, an organic layer, an organic electronics element, an organic electroluminescence element (also referred to as “organic EL element”), a display element, a lighting device, and a display device.

Organic EL devices are attracting attention as large-area solid-state light source applications as alternatives to incandescent lamps and gas-filled lamps. It is also attracting attention as the most powerful 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 organic EL elements using low molecular compounds and high molecular organic EL elements using high molecular compounds, depending on the organic materials used. The manufacturing method of the organic EL element includes a dry process in which film formation is mainly performed in a vacuum system and a wet process in which film formation is performed by plate printing such as letterpress printing and intaglio printing, and plateless printing such as inkjet. There are two main types. Since simple film formation is possible, the wet process is expected as an indispensable method for future large-screen organic EL displays (see, for example, Patent Document 1).

JP 2006-279007 A

An organic EL device manufactured using a wet process has the feature that it is easy to reduce the cost and increase the area. However, there is room for further improvement regarding the characteristics of the organic EL element.

In view of the above, it is an object of an embodiment of the present invention to provide an organic electronic material and an ink composition that are suitable for a wet process and suitable for improving the charge transportability of an organic layer. It is an object of another embodiment of the present invention to provide an organic layer having excellent charge transportability. Furthermore, another embodiment of the present invention has an object to provide an organic electronics element, an organic EL element, a display element, a lighting device, and a display device including an organic layer having excellent charge transporting properties.

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

One embodiment relates to an organic electronic material containing a charge transporting polymer or oligomer having a branched structure and having a structural unit including a partial structure represented by the following formula (1).

(In the formula (1), each Ra independently represents a hydrogen atom or a substituent. Each Rb independently represents a hydrogen atom, a substituent, or a bonding site with another structure, and One is the binding site with other structures.)

Another embodiment relates to an ink composition containing the organic electronic material and a solvent.

Another embodiment relates to an organic layer formed using the organic electronic material or the ink composition.

Another embodiment relates to an organic electronic device including at least one organic layer.

Another embodiment relates to an organic electroluminescence device including at least one organic layer.

In another embodiment, a display element comprising the organic electroluminescence element; a lighting device comprising the organic electroluminescence element; and a display comprising the lighting device and a liquid crystal element as a display means Relates to the device.

According to the embodiment of the present invention, it is possible to provide an organic electronic material and an ink composition that are suitable for a wet process and suitable for improving the charge transportability of an organic layer. In addition, according to another embodiment of the present invention, an organic layer having excellent charge transportability can be provided. Furthermore, according to other embodiment of this invention, the organic electronics element provided with the organic layer which has the outstanding electric charge transportability, an organic EL element, a display element, an illuminating device, and a display apparatus can be provided.

FIG. 1 is a schematic cross-sectional view showing an example of an organic EL element according to an embodiment of the present invention.

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

<Organic electronics materials>
The organic electronic material which is one embodiment contains a charge transporting polymer or oligomer having a branched structure and a structural unit including a partial structure represented by the formula (1). The organic electronic material may contain only one kind or two or more kinds of charge transporting polymers or oligomers. The charge transporting polymer or oligomer is preferable in that the film forming property in the wet process is excellent as compared with the low molecular compound.

In formula (1), each Ra independently represents a hydrogen atom or a substituent. Rb independently represents a hydrogen atom, a substituent, or a bonding site with another structure. At least one of Rb is a binding site with another structure.

When the charge transporting polymer or oligomer has a partial structure represented by the formula (1), an arylamine structure and a thiophene structure, which are good hole transporting sites, are introduced, and the hole transporting property is improved. Conceivable. In particular, when the charge transporting polymer or oligomer has a structural unit including the partial structure represented by the formula (1) and a structural unit having a hole transporting property, it exhibits high hole transporting ability. The “structural unit having a hole transporting property” is a structural unit different from the “structural unit including the partial structure represented by the formula (1)”. It is considered that the charge transporting polymer or oligomer can exhibit high performance as an organic electronic material by having the partial structure represented by the formula (1).

[Charge transporting polymer or oligomer]
A charge transporting polymer or oligomer is a polymer or oligomer having the ability to transport charge. In the following description, “charge transporting polymer or oligomer” is also referred to as “charge transporting polymer”.

(Structural unit including the partial structure represented by Formula (1))
The charge transporting polymer has a structural unit including a partial structure represented by the following formula (1). In the following description, “partial structure represented by formula (1)” is also referred to as “partial structure (1)”, and “structural unit including the partial structure represented by formula (1)” is “structural unit (1 ) ". The charge transporting polymer may contain only one type of structural unit (1), or may contain two or more types.

In formula (1), each Ra independently represents a hydrogen atom or a substituent. Rb each independently represents a hydrogen atom, a substituent, or a binding site with another structure, and at least one of Rb is a binding site with another structure.

Examples of the substituent include —R ¹ , —OR ² , —SR ³ , —OCOR ⁴ , —COOR ⁵ , —SiR ⁶ R ⁷ R ⁸ , a halogen atom, and a group containing a polymerizable functional group described later. And a substituent selected from the group (hereinafter, also referred to as “substituent a”).

R ¹ is selected from the group consisting of alkyl groups, alkenyl groups, alkynyl groups, alkoxy groups, aryl groups, and heteroaryl groups.

R ² to R ⁸ are each independently selected from the group consisting of a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an alkoxy group, an aryl group, and a heteroaryl group.

The alkyl group, alkenyl group, alkynyl group and alkoxy group may be linear, branched or cyclic. The alkyl group, alkenyl group, alkynyl group, and alkoxy group preferably have 1 to 22 carbon atoms. The number of carbon atoms of the aryl group is preferably 6-30. The carbon number of the heteroaryl group is preferably 2-30. The alkyl group, alkenyl group, alkynyl group, alkoxy group, aryl group, and heteroaryl group may be substituted or unsubstituted. The alkenyl group and alkynyl group may exhibit polymerizability, and the alkenyl group and alkynyl group exhibiting polymerizability correspond to groups containing a polymerizable functional group described later.

Examples of the substituent in the case where the alkyl group, alkenyl group, alkynyl group, alkoxy group, aryl group, and heteroaryl group further have a substituent include the above-mentioned substituent a, preferably —R ¹ .

When the charge transporting polymer has a polymerizable functional group, at least one of Ra may be a group containing a polymerizable functional group. The thiophen-yl group contained in the partial structure (1) may exhibit polymerizability, and the thiophen-yl group showing the polymerizability contained in the partial structure (1) corresponds to a group containing a polymerizable functional group described later. To do.

Examples of the alkyl group include methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n- Decyl, n-undecyl, n-dodecyl, isopropyl, isobutyl, sec-butyl, tert-butyl, 2-ethylhexyl, 3,7-dimethyloctyl, cyclohexyl, cycloheptyl, cyclo An octyl group etc. are mentioned.

In the present specification, an aryl group is an atomic group obtained by removing one hydrogen atom from an aromatic hydrocarbon. A heteroaryl group is an atomic group obtained by removing one hydrogen atom from an aromatic heterocyclic ring.

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

Examples of aromatic hydrocarbons include benzene, naphthalene, anthracene, tetracene, fluorene, phenanthrene, biphenyl, terphenyl, triphenylbenzene, and the like. Examples of aromatic heterocycles include pyridine, pyrazine, quinoline, isoquinoline, acridine, phenanthroline, furan, benzofuran, dibenzofuran, pyrrole, thiophene, benzothiophene, dibenzothiophene, carbazole, oxazole, oxadiazole, thiadiazole, triazole, benzoxazole , Benzoxadiazole, benzothiadiazole, benzotriazole, benzothiophene and the like.

When Ra includes a substituent, the substituent preferably includes —R ¹ , more preferably includes at least one selected from an alkyl group and a heteroaryl group, and more preferably includes an alkyl group. As the alkyl group, an alkyl group having 1 to 8 carbon atoms is preferable, and an alkyl group having 1 to 4 carbon atoms is more preferable. As the heteroaryl group, a condensed ring is preferable, and a carbazolyl group is more preferable. The carbazolyl group is preferably a 9-carbazolyl group.

Rb each independently represents a hydrogen atom, a substituent, or a bonding site with another structure. Examples of the substituent include the substituent a.

At least one of Rb is a binding site with another structure. “Other structures” are structures other than hydrogen atoms and the above-described substituents. When three of Rb are binding sites, partial structure (1) is a trivalent structure, and when two of Rb are binding sites, partial structure (1) is a divalent structure, and one of Rb is When it is a binding site, the partial structure (1) is a monovalent structure. The partial structure (1) is preferably divalent or trivalent, and more preferably trivalent because a higher effect of improving charge transportability is obtained.

When at least one of Ra and Rb contains a substituent, the total number of substituents contained in the partial structure (1) is preferably 1 to 6, and more preferably 1 to 5. When a plurality of substituents are present, the plurality of substituents may be the same as or different from each other.

Ra which is not a substituent and Rb which is not a substituent and a binding site are a hydrogen atom. The number of hydrogen atoms is 0 to 8, and preferably 3 to 8. All Ra and Rb other than the binding site may be hydrogen atoms.

The partial structure (1) is preferably a partial structure represented by the following formula (1-1). When the partial structure (1) is a partial structure represented by the formula (1-1), a high effect of improving the charge transportability can be obtained. A charge transporting polymer can also be easily produced.

In the formula (1-1), each Ra independently represents a hydrogen atom or a substituent. Rb each independently represents a hydrogen atom, a substituent, or a binding site with another structure, and at least one of Rb is a binding site with another structure. Examples of the substituent include the substituent a.

Examples of partial structure (1) are given below. The partial structure (1) is not limited to the structure represented by the following formula. In the present specification, “*” represents a binding site with another structure.

In the above formula, each R independently represents a substituent. n independently represents an integer of 0 to 2. n represents the number of Rs. Examples of the substituent include the substituent a. When several R exist, R may mutually be same or different.

Preferred specific examples of partial structure (1) are listed below. The partial structure (1) is not limited to the structure represented by the following formula.

The structural unit (1) is a structural unit having at least one partial structure (1). The structural unit (1) is preferably monovalent to hexavalent, and more preferably monovalent to trivalent. The structural unit (1) is preferably divalent or trivalent, and more preferably trivalent because a higher effect of improving charge transportability is obtained.

Examples of structural unit (1) are listed below. The structural unit (1) is not limited to the structure represented by the following formula.

In the above formula, each A independently represents a partial structure (1), each B independently represents a partial structure containing at least one selected from an aromatic hydrocarbon structure and an aromatic heterocyclic structure, and Y Represents a direct bond or a divalent linking group.
The divalent linking group is, for example, a divalent linking group in which one hydrogen atom is further removed from a group having one or more hydrogen atoms in the substituent a (excluding a group containing a polymerizable functional group). It is a group.

When the partial structure (1) is contained in the charge transporting polymer as a structural unit forming a skeleton structure of a molecular chain, a high effect of improving the charge transporting property tends to be obtained. From this point of view, the structural unit (1) has the formulas (L1-1) to (L1-5), formulas (B1-1) to (B1-11), and formulas (T1-1) and (T1-2). It is preferable that it is a structural unit represented by either. The structural unit (1) is represented by any one of the formula (L1-1), the formula (B1-1), and the formula (T1-1) because a higher effect of improving the charge transport property can be obtained. It is preferably a structural unit, more preferably a structural unit represented by any one of formulas (L1-1) and (B1-1), and a unit represented by formula (B1-1). More preferably. These units are preferable units because they tend to easily synthesize desired charge transporting polymers.

Partial structure (1) may be included in the charge transporting polymer as a substituent to the backbone structure of the molecular chain. When included as a substituent in the skeleton structure of the molecular chain, the structural unit (1) is, for example, a structural unit represented by any one of formulas (L1-6) to (L1-8). Specifically, structural units that are the same as the structural units listed as specific examples in the description of the structural unit L2 to be described later are given except that R ′ is substituted for R. R ′ represents a hydrogen atom or a substituent, and the substituent is preferably each independently a substituent a or a partial structure (1). In each structural unit, at least one of R ′ is the partial structure (1).

(Structure of charge transporting polymer)
The charge transporting polymer has the structural unit (1). The charge transporting polymer preferably further has a structural unit having a hole transporting property. The charge transporting polymer is a branched polymer having a branched structure. The structural unit constituting the charge transporting polymer preferably includes a trivalent or higher valent structural unit B and a monovalent structural unit T. The structural unit constituting the charge transporting polymer may further include a divalent structural unit L. The structural unit B is a structural unit that constitutes the branch portion. The structural unit L is preferably a structural unit having charge transporting properties. The structural unit T is a structural unit that constitutes the terminal portion of the molecular chain. The charge transporting polymer preferably includes at least a trivalent or higher structural unit B constituting a branched portion, a divalent structural unit L having charge transporting property, and a monovalent structural unit T constituting a terminal portion. Including.

The charge transporting polymer may contain only one kind of each structural unit, or may contain plural kinds of structural units. In the charge transporting polymer, each structural unit is bonded to each other at a binding site of “monovalent” to “trivalent or more”.

According to a preferred embodiment, the branched structure has at least one branch part and three or more chains bonded to one of the at least one branch part. More preferably, the branched structure has at least one branch part and three or more chains bonded to one of the at least one branch part, and each of the three or more chains has a separate structure. And a multi-branch structure having at least one other branched portion and two or more chains bonded to one of the at least one other branched portion. Here, the “chain” is a connection of structural units including at least the structural unit L, preferably a structural unit composed of the structural unit L, the structural unit B (unit that can be optionally included), and the structural unit T. Connection.

According to a preferred embodiment, the branched structure has at least one structural unit B and three or more structural units L bonded to one of the at least one structural unit B. Preferably, the branched structure includes at least one structural unit B and three or more structural units L bonded to one of the at least one structural unit B, and further includes the three or more structural units L. Each includes a multi-branched structure having another structural unit B bonded to the structural unit L and two or more other structural units L bonded to the other structural unit B.

The charge transporting polymer has at least one structural unit (1) as at least one selected from the group consisting of “structural unit B”, “structural unit L”, and “structural unit T”. Preferred examples of the charge transporting polymer are listed below. The charge transporting polymer preferably satisfies at least one of (A) and (B), and more preferably satisfies at least (A), since a high effect of improving the charge transporting property tends to be obtained.
(A) Charge transporting polymer having structural unit B, structural unit L, and structural unit T, wherein structural unit L includes structural unit (1) (B) having at least structural unit B and structural unit T A charge transporting polymer in which structural unit B includes structural unit (1) (C) charge transporting polymer having at least structural unit B and structural unit T, wherein structural unit T includes structural unit (1) D) Charge transporting polymer comprising structural unit B, structural unit L, and structural unit T, wherein at least one selected from the group consisting of structural unit B, structural unit L, and structural unit T includes structural unit (1)

The charge transporting polymer having the structural unit (1) preferably further has a structural unit having a hole transporting property. The structural unit having a hole transporting property is not particularly limited as long as it contains an atomic group having an ability to transport charges. The structural unit having a hole transporting property may be monovalent, divalent, or trivalent or higher. The charge transporting polymer has at least one structural unit having a hole transporting property as at least one selected from the group consisting of “structural unit B”, “structural unit L”, and “structural unit T”. The structural unit having a hole transporting property is preferably included as a structural unit forming a skeleton structure of a molecular chain in the charge transporting polymer.

Preferred examples of the charge transporting polymer having a structural unit having a hole transporting property are listed below. The following charge transporting polymers (a) to (c) also have a structural unit (1). The charge transporting polymer preferably satisfies at least one of (a) and (b), and more preferably satisfies at least (b), since a high effect of improving the charge transporting property tends to be obtained.
(A) a charge transporting polymer having a structural unit B, a structural unit L, and a structural unit T, wherein the structural unit L includes a structural unit having a hole transporting property; and (b) the structural unit B and the structural unit T. A charge transporting polymer having at least a structural unit in which the structural unit B has a hole transporting property (c) having a structural unit B, a structural unit L, and a structural unit T; Charge transporting polymer, wherein at least one selected from the group consisting of structural units having a hole transporting property

The charge transporting polymer comprising the structural unit (1) and the structural unit having a hole transporting property is at least one selected from the group consisting of the above (A) to (D), and the above (a ) To (c), and is preferably a charge transporting polymer satisfying at least one selected from the group consisting of. More preferably, it is a charge transporting polymer satisfying at least (A) and (b) or a charge transporting polymer satisfying at least (B) and (a), and a charge satisfying at least (A) and (b). More preferably, it is a transportable polymer.

The structural unit having a hole transporting property is selected from the group consisting of a substituted or unsubstituted aromatic amine structure, a substituted or unsubstituted carbazole structure, a substituted or unsubstituted thiophene structure, and a substituted or unsubstituted fluorene structure. It is preferable that the structural unit contains one or more partial structures. From the viewpoint of having high hole injecting property, hole transporting property, etc., a structural unit comprising one or more partial structures selected from the group consisting of a substituted or unsubstituted aromatic amine structure and a substituted or unsubstituted carbazole structure It is preferable that The aromatic amine structure is preferably a triarylamine structure, more preferably a triphenylamine structure.

Examples of the partial structure contained in the charge transporting polymer include the following. 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 partial structures, the plurality of Bs may be the same structural unit or different structural units. The same applies to L and T. The charge transporting polymer is not limited to those having the following partial structure.

Charge transporting polymer having a branched structure

(Structural unit B)
The structural unit B is a trivalent or higher valent structural unit constituting a branched portion in a charge transporting polymer having a structure branched in three or more directions. The charge transporting polymer may have only one type of structural unit B, or may have two or more types. The structural unit B is preferably hexavalent or less, more preferably trivalent or tetravalent, from the viewpoint of improving the durability of the organic electronic element. As an example of the structural unit B, a trivalent structural unit (1) (hereinafter also referred to as “structural unit B1”) and a structural unit not including the partial structure (1) (hereinafter also referred to as “structural unit B2”). ).

The structural unit B2 is preferably a structural unit having a charge transporting property, and more preferably a structural unit having a hole transporting property. The structural unit B2 is not particularly limited. For example, from the viewpoint of improving the durability of the organic electronics element, the substituted or unsubstituted aromatic amine structure, carbazole structure, condensed polycyclic aromatic hydrocarbon structure, and these It is selected from the structure containing 1 type, or 2 or more types. The aromatic amine structure is preferably a triarylamine structure, more preferably a triphenylamine structure.

Specific examples of the structural unit B2 include the following. The structural unit B2 is not limited to the following.

W represents a trivalent linking group, for example, an arenetriyl group or a heteroarenetriyl group having 2 to 30 carbon atoms.
Ar each independently represents a divalent linking group, for example, each independently represents an arylene group or heteroarylene group having 2 to 30 carbon atoms. Ar is preferably an arylene group, more preferably a phenylene group. Y represents a divalent linking group. For example, one R atom in the structural unit L (excluding a group containing a polymerizable functional group) has one more hydrogen atom from a group having one or more hydrogen atoms. And divalent groups excluding.
Z represents any of a carbon atom, a silicon atom, or a phosphorus atom.
In the structural unit, W, the benzene ring, and Ar may have a substituent (however, the partial structure represented by the formula (1) is not included). As an example of the substituent, the substituent a is Can be mentioned.

In the present specification, an arylene group is an atomic group obtained by removing two hydrogen atoms from an aromatic hydrocarbon. A heteroarylene group is an atomic group obtained by removing two hydrogen atoms from an aromatic heterocycle. The arenetriyl group is an atomic group obtained by removing three hydrogen atoms from an aromatic hydrocarbon. The heteroarene triyl group is an atomic group obtained by removing three hydrogen atoms from an aromatic heterocyclic ring.

(Structural unit L)
The structural unit L is a divalent structural unit. The charge transporting polymer may have only one type of structural unit L, or may have two or more types. As examples of the structural unit L, a divalent structural unit (1) (hereinafter also referred to as “structural unit L1”) and a structural unit not including the partial structure (1) (hereinafter also referred to as “structural unit L2”). ).

The structural unit L2 is preferably a structural unit having a charge transporting property, and more preferably a structural unit having a hole transporting property. The structural unit having charge transporting properties is not particularly limited as long as it contains an atomic group having the ability to transport charges. For example, the structural unit L2 is a substituted or unsubstituted aromatic amine structure, carbazole structure, thiophene structure, fluorene structure, benzene structure, biphenyl structure, terphenyl structure, naphthalene structure, anthracene structure, tetracene structure, phenanthrene structure, dihydro Phenanthrene structure, pyridine structure, pyrazine structure, quinoline structure, isoquinoline structure, quinoxaline structure, acridine structure, diazaphenanthrene structure, furan structure, pyrrole structure, oxazole structure, oxadiazole structure, thiazole structure, thiadiazole structure, triazole structure, benzo Thiophene structure, benzoxazole structure, benzooxadiazole structure, benzothiazole structure, benzothiadiazole structure, benzotriazole structure, and one or two of these It is selected from a structure including more. The aromatic amine structure is preferably a triarylamine structure, more preferably a triphenylamine structure. The structural unit L2 may have the same structure as the structural unit B2 or a different structure with respect to other than the valence.

In one embodiment, the structural unit L2 has a substituted or unsubstituted aromatic amine structure, carbazole structure, thiophene structure, fluorene structure, benzene structure, pyrrole structure, and these from the viewpoint of obtaining excellent hole transport properties. Are preferably selected from structures containing one or more of these, more preferably selected from substituted or unsubstituted aromatic amine structures, carbazole structures, and structures containing one or more of these. preferable. In another embodiment, the structural unit L2 is a substituted or unsubstituted fluorene structure, benzene structure, phenanthrene structure, pyridine structure, quinoline structure, and one or two kinds thereof from the viewpoint of obtaining excellent electron transport properties. It is preferable to select from a structure including the above.

Specific examples of the structural unit L2 include the following. The structural unit L2 is not limited to the following.

In the formula, each R independently represents a hydrogen atom or a substituent (however, the partial structure represented by the formula (1) is not included). Examples of the substituent include the substituent a. R is preferably a hydrogen atom, an alkyl group, an aryl group, or an alkyl-substituted aryl group.
Ar represents an arylene group or heteroarylene group having 2 to 30 carbon atoms. Ar is preferably an arylene group, more preferably a phenylene group.

(Structural unit T)
The structural unit T is a monovalent structural unit constituting the terminal portion of the charge transporting polymer. The charge transporting polymer may have only one type of structural unit T, or may have two or more types. When the charge transporting polymer has a polymerizable functional group at the terminal portion, the structural unit T may have a group containing a polymerizable functional group. As examples of the structural unit T, a monovalent structural unit (1) (hereinafter also referred to as “structural unit T1”) and a structural unit not including the partial structure (1) (hereinafter also referred to as “structural unit T2”). ).

The structural unit T2 is preferably a structural unit having a charge transporting property, and more preferably a structural unit having a hole transporting property. The structural unit T2 is not particularly limited, and is selected from, for example, a substituted or unsubstituted aromatic hydrocarbon structure, aromatic heterocyclic structure, and a structure including one or more of these. In one embodiment, the structural unit T2 is preferably a substituted or unsubstituted aromatic hydrocarbon structure from the viewpoint of imparting durability without deteriorating charge transportability, and is preferably a substituted or unsubstituted benzene structure. A structure is more preferable. In another embodiment, when the charge transporting polymer has a polymerizable functional group at the terminal portion, the structural unit T2 has a polymerizable structure (that is, a polymerizable functional group such as a pyrrol-yl group). It may have a polymerizable functional group. The structural unit T2 may have the same structure as the structural unit B2 or a different structure with respect to other than the valence. The structural unit T2 may have the same structure as the structural unit L2 or a different structure with respect to other than the valence.

Specific examples of the structural unit T2 include the following. The structural unit T2 is not limited to the following.

In the formula, R is the same as R in the structural unit L2. When the charge transporting polymer has a polymerizable functional group at the terminal portion, at least one of R is preferably a group containing a polymerizable functional group.

(Polymerizable functional group)
In one embodiment, the charge transporting polymer preferably has at least one polymerizable functional group from the viewpoint of curing by a polymerization reaction and changing the solubility in a solvent. The “polymerizable functional group” refers to a functional group that can form a bond with each other by applying heat and / or light. The polymerizable functional group may be contained in the structural unit (1), or may be contained in a structural unit other than the structural unit (1).

Examples of the polymerizable functional group include substituted or unsubstituted groups having a carbon-carbon multiple bond (for example, vinyl group, styryl group, allyl group, butenyl group, ethynyl group, acryloyl group, acryloyloxy group, acryloylamino group, A methacryloyl group, a methacryloyloxy group, a methacryloylamino group, a vinyloxy group, a vinylamino group, etc.), a group having a small ring (for example, a cyclic alkyl group such as a cyclopropyl group, a benzocyclobutenyl group, a cyclobutyl group; an epoxy group ( A group having a cyclic ether structure such as an oxiranyl group) or an oxetane group (oxetanyl group); a diketene group; an episulfide group; a lactone group; a lactam group, etc.), a heterocyclic group (eg, furanyl group, pyrroleyl group, thiophene) -Yl group, silyl-yl group) and the like.

The substituent in the case where these groups are substituted is not particularly limited, and examples thereof include a linear, cyclic or branched alkyl group. The alkyl group preferably has 1 to 22 carbon atoms, more preferably 1 to 10 carbon atoms.

The polymerizable functional group is preferably a substituted or unsubstituted group having a cyclic ether structure and a group having a carbon-carbon multiple bond, and is a substituted or unsubstituted vinyl group, styryl group, acryloyl group, methacryloyl group, epoxy. Group and oxetane group are more preferable, and from the viewpoint of reactivity and characteristics of the organic electronic device, a substituted or unsubstituted vinyl group, styryl group, oxetane group, and epoxy group are more preferable, and vinyl group and styryl group are particularly preferable. preferable.

From the viewpoint of increasing the degree of freedom of the polymerizable functional group and facilitating the occurrence of a polymerization reaction, the skeleton structure of the charge transporting polymer and the polymerizable functional group are alkylene chains (for example, linear chains having 1 to 8 carbon atoms). It may be bonded via a linking group such as an alkylene chain. In addition, for example, when an organic layer is formed on an electrode, it is bonded via a hydrophilic linkage such as an ethylene glycol chain or a diethylene glycol chain from the viewpoint of improving the affinity with a hydrophilic electrode such as ITO. Also good. Furthermore, from the viewpoint of facilitating preparation of a monomer used for introducing a polymerizable functional group, one or more selected from an ether bond, an ester bond, and the like are included between the skeleton structure and the polymerizable functional group. It may have a linking group.

Examples of the above-mentioned “group containing a polymerizable functional group” include “polymerizable functional group” itself and “a group in which a polymerizable functional group is combined with a linking group such as an alkylene chain or an ether bond”. As the group containing a polymerizable functional group, for example, groups exemplified in International Publication No. 2010/140553 can be preferably used.

The polymerizable functional group may be introduced into the terminal part (that is, the structural unit T) of the charge transporting polymer, or may be introduced into a part other than the terminal part (that is, the structural unit L or B). And may be introduced into both parts other than the terminal part. From the viewpoint of curability, it is preferably introduced at least at the end portion, and from the viewpoint of achieving both curability and charge transportability, it is preferably introduced only at the end portion. The polymerizable functional group may be introduced into the main chain of the charge transporting polymer, may be introduced into the side chain, or may be introduced into both the main chain and the side chain.

From the viewpoint of contributing to the change in solubility, it is preferable that a large amount of the polymerizable functional group is contained 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, more preferably 3 or more from the viewpoint of obtaining a sufficient solubility change and facilitating multilayering. 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 used to synthesize the charge transporting polymer (for example, the amount of the monomer having a polymerizable functional group), each structure The average value can be obtained by using the monomer charge corresponding to the unit and the weight average molecular weight of the charge transporting polymer. The number of polymerizable functional groups is the ratio between the integral value of the signal derived from the polymerizable functional group and the integral value of the entire spectrum in the ¹ H NMR (nuclear magnetic resonance) spectrum of the charge transporting polymer, the charge transporting polymer The weight average molecular weight can be used to calculate the average value.

(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 formability, and the like. The number average molecular weight is preferably 500 or more, more preferably 1,000 or more, and still more preferably 2,000 or more, from the viewpoint of excellent charge transportability. The number average molecular weight is preferably 1,000,000 or less, more preferably 100,000 or less, and more preferably 50,000 from the viewpoint of maintaining good solubility in a solvent and facilitating the preparation of an ink composition. The following is more preferable.

(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 formability, and the like. The weight average molecular weight is preferably 1,000 or more, more preferably 3,000 or more, and further preferably 5,000 or more, from the viewpoint of excellent charge transportability. Further, the weight average molecular weight is preferably 1,000,000 or less, more preferably 700,000 or less, and more preferably 400,000 from the viewpoint of maintaining good solubility in a solvent and facilitating preparation of an ink composition. The following is more preferable, and 300,000 or less is most preferable.

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.

(Percentage of structural units)
The proportion of the structural unit (1) contained in the charge transporting polymer is preferably 1 mol% or more, more preferably 5 mol% or more, more preferably 10 mol%, based on the total structural unit, from the viewpoint of improving the characteristics of the organic electronics element. The above is more preferable. In particular, from the viewpoint of obtaining the effect of improving characteristics, 25 mol% or more is preferable, and 40 mol% or more is more preferable. An upper limit is not specifically limited, It is 100 mol% or less. For example, when the charge transporting polymer further has a structural unit having a hole transporting property, the proportion of the structural unit (1) is preferably 70 mol% or less, more preferably 60 mol% or less, and further preferably 50 mol% or less. preferable.

The proportion of the structural unit having hole transporting property contained in the charge transporting polymer is preferably 5 mol% or more, more preferably 10 mol% or more, based on the total structural unit, from the viewpoint of improving the characteristics of the organic electronics element. 25 mol% or more is more preferable. The upper limit is less than 100 mol%.

The proportion of the structural unit B contained in the charge transporting polymer is preferably 1 mol% or more, more preferably 5 mol% or more, more preferably 10 mol%, based on the total structural unit, from the viewpoint of improving the durability of the organic electronics element. The above is more preferable. The proportion of the structural unit B is preferably 50 mol% or less, preferably 40 mol% or less, from the viewpoint of suppressing the increase in viscosity and satisfactorily synthesizing the charge transporting polymer or obtaining sufficient charge transportability. Is more preferable, and 30 mol% or less is still more preferable.

When the charge transporting polymer includes the structural unit L, the proportion of the structural unit L is preferably 10 mol% or more, more preferably 20 mol% or more, based on the total structural unit, from the viewpoint of obtaining sufficient charge transportability. 30 mol% or more is more preferable. In consideration of the structural unit B and the structural unit T, the proportion of the structural unit L is preferably 95 mol% or less, more preferably 90 mol% or less, and still more preferably 85 mol% or less.

The proportion of the structural unit T contained in the charge transporting polymer is based on the total structural unit from the viewpoint of improving the characteristics of the organic electronics element or suppressing the increase in the 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 still more preferable. The proportion of the structural unit T is preferably 60 mol% or less, more preferably 55 mol% or less, and still more preferably 50 mol% or less from the viewpoint of obtaining sufficient charge transport properties.

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

In consideration of the balance of charge transportability, durability, productivity, etc., in the case of a charge transporting polymer containing the structural unit L, the structural unit T, and the structural unit B, the ratio (molar ratio) of these structural units is L : T: B = 100: 10 to 400: 10 to 300 is preferable, 100: 20 to 300: 20 to 200 is more preferable, and 100: 40 to 200: 30 to 100 is still more preferable.

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

Preferred examples of the charge transporting polymer are listed below.
(1) Charge transporting polymer having at least the structural unit L1, the structural unit B2, and the structural unit T2 The charge transporting polymer may further include the structural unit L2 for adjusting the charge transporting property and the like.
(2) Charge transporting polymer having at least the structural unit L2, the structural unit B1, and the structural unit T2 The charge transporting polymer may further include the structural unit B2 for the purpose of adjusting the charge transporting property and the like.
(3) Charge transporting polymer having at least the structural unit L2, the structural unit B2, and the structural unit T1 The charge transporting polymer may further include the structural unit T2 in order to adjust solubility, curability, and the like. .

In (1) to (3), the structural unit B2 and the structural unit L2 are preferably each independently a structural unit having a hole transporting property, and are a substituted or unsubstituted aromatic amine structure, substituted or unsubstituted. It is preferably a structural unit containing at least one partial structure selected from the group consisting of a carbazole structure, a substituted or unsubstituted thiophene structure, and a substituted or unsubstituted fluorene structure, and a substituted or unsubstituted aromatic amine It is more preferably a structural unit including a structure and at least one partial structure selected from the group consisting of a substituted or unsubstituted carbazole structure.

In (1) to (3), the structural unit T2 is preferably a structural unit containing a substituted or unsubstituted aromatic hydrocarbon structure, more preferably a structural unit containing a substituted or unsubstituted benzene structure. preferable.

The charge transporting polymer is preferably a polymer satisfying (1) or (2), and more preferably a polymer satisfying (1).

The polymerization degree (number of structural units) of the charge transporting polymer is preferably 5 or more, more preferably 10 or more, and still more preferably 20 or more, from the viewpoint of stabilizing the film quality of the organic layer. 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 obtained as an average value 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.

(Production method)
The charge transporting polymer can be produced by various synthetic methods and is not particularly limited. For example, it can be produced by polymerizing a monomer for forming the structural unit of the charge transporting polymer. The charge transporting polymer is preferably a copolymer of a monomer mixture containing at least a monomer having the structural unit (1) and a monomer having a structural unit having a hole transporting property. For example, the monomer mixture preferably includes a monomer having the structural unit (1), a monomer having the structural unit L2, and / or a monomer having the structural unit B2. The monomer mixture may optionally contain one or more monomers other than those described above (for example, a monomer having the structural unit T2). The charge transporting polymer may be a polymer of a monomer including only one monomer having the structural unit (1). Further, the charge transporting polymer may be a copolymer of a monomer mixture containing two or more monomers having only the structural unit (1).

The proportion of the monomer having the structural unit (1) in the monomer mixture is preferably 1 mol% or more, more preferably 25 mol% or more, based on the total monomers in the monomer mixture, from the viewpoint of improving the characteristics of the organic electronic device. More preferably, it is 40 mol% or more. An upper limit is not specifically limited, It is 100 mol% or less. For example, when the monomer mixture further contains any of the monomer having the structural unit L2, the monomer having the structural unit B2, and the monomer having the structural unit T2, the proportion of the structural unit (1) is preferably 70 mol% or less. 60 mol% or less is more preferable, and 50 mol% or less is still more preferable.

In the monomer mixture, the ratio of the total of at least one selected from the group consisting of the monomer having the structural unit B2, the monomer having the structural unit L2, and the monomer having the structural unit T2 is a monomer from the viewpoint of improving the characteristics of the organic electronics element. Preferably, it is 5 mol% or more, more preferably 10 mol% or more, and still more preferably 25 mol% or more, based on the total monomers in the mixture. An upper limit is not specifically limited, It is less than 100 mol%.

When a monomer mixture is used, a charge transporting polymer can be easily produced by copolymerizing the monomers. The type of copolymerization may be an alternating, random, block or graft copolymer, or a copolymer having an intermediate structure thereof, for example, a random copolymer having a block property. .

The polymerization reaction is preferably a coupling reaction. Examples of the coupling reaction include known reactions such as Suzuki coupling, Negishi coupling, Sonogashira coupling, Stille coupling, Buchwald-Hartwig coupling, etc. Can be used. Suzuki coupling causes a cross coupling reaction using a Pd catalyst between an aromatic boronic acid derivative and an aromatic halide. According to Suzuki coupling, a charge transporting polymer can be easily produced by bonding desired aromatic rings together.

In the coupling reaction, for example, a Pd (0) compound, a Pd (II) compound, a Ni compound, or the like is used as a catalyst. In addition, a catalyst species generated by mixing tris (dibenzylideneacetone) dipalladium (0), palladium (II) acetate and the like with a phosphine ligand can also be used. For the method for synthesizing the charge transporting polymer, for example, the description in WO 2010/140553 can be referred to.

Examples of monomers that can be used in the Suzuki coupling reaction include the following.

(Monomer L)

(Monomer B)

(Monomer T)

In the formula, L represents a divalent structural unit, B represents a trivalent or tetravalent structural unit, and T represents a monovalent structural unit. R ¹ to R ³ each represents a functional group capable of forming a bond with each other. For example, each of R ¹ to R ³ independently represents any one selected from the group consisting of a boronic acid group, a boronic ester group, and a halogen group. To express. The monomer used includes the structural unit (1) as at least one of “L”, “B”, and “T”.

These monomers can be synthesized by a known method. These monomers are available from, for example, Tokyo Chemical Industry Co., Ltd., Sigma Aldrich Japan LLC.

[Dopant]
The organic electronic material can contain any additive, for example, it may further contain a dopant. The dopant is not particularly limited as long as it can be added to the organic electronic material to develop a doping effect and improve the charge transport property. Doping includes p-type doping and n-type doping. In p-type doping, a substance serving as an electron acceptor is used as a dopant, and in n-type doping, a substance serving as an electron donor is used as a dopant. It is preferable to perform p-type doping for improving hole transportability and n-type doping for improving electron transportability. The dopant used in the organic electronic material may be a dopant that exhibits any effect of p-type doping or n-type doping. One kind of dopant may be added alone, or plural 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 acids, proton acids, transition metal compounds, ionic compounds, halogen compounds, and π-conjugated compounds. Specifically, as the Lewis acid, FeCl ₃ , PF ₅ , AsF ₅ , SbF ₅ , BF ₅ , BCl ₃ , BBr _{3 and the} like; as the protonic acid, HF, HCl, HBr, HNO ₅ , H ₂ SO ₄ , HClO _{4 and} other inorganic acids, benzenesulfonic acid, p-toluenesulfonic acid, dodecylbenzenesulfonic acid, polyvinylsulfonic acid, methanesulfonic acid, trifluoromethanesulfonic acid, trifluoroacetic acid, 1-butanesulfonic acid, vinylphenylsulfonic acid Organic acids such as camphorsulfonic acid; transition metal compounds include FeOCl, TiCl ₄ , ZrCl ₄ , HfCl ₄ , NbF ₅ , AlCl ₃ , NbCl ₅ , TaCl ₅ , MoF ₅ ; Phenyl) borate ion, tris (trifluoro) Methanesulfonyl) Mechidoion, bis (trifluoromethanesulfonyl) imide ion, hexafluoroantimonate ion, AsF ₆ ^- (hexafluoro arsenic acid ions), BF ₄ ^- (tetrafluoroborate), PF ₆ ^- (hexafluorophosphate) A salt having a perfluoroanion such as a salt, a salt having a conjugate base of the protonic acid as an anion; halogen compounds such as Cl ₂ , Br ₂ , I ₂ , ICl, ICl ₃ , IBr and IF; π-conjugated compounds Examples thereof include TCNE (tetracyanoethylene), TCNQ (tetracyanoquinodimethane) and the like. It is also possible to use known electron-accepting compounds other than those described above. Preferred are Lewis acids, ionic compounds, π-conjugated compounds and the like.

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

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

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

[Content]
The content of the charge transporting polymer in the organic electronic material is preferably 50% by mass or more, more preferably 70% by mass or more based on the total mass of the organic electronic material from the viewpoint of obtaining good charge transporting property. 80 mass% or more is more preferable. The upper limit of the content of the charge transporting polymer is not particularly limited, and may be 100% by mass. Considering that an additive such as a dopant is included, the content of the charge transporting polymer may be, for example, 95% by mass or less or 90% by mass or less.

When the dopant is contained, the content is preferably 0.01% by mass or more, and 0.1% by mass or more with respect to the total mass of the organic electronic material from the viewpoint of improving the charge transport property of the organic electronic material. More preferred is 0.5% by mass or more. Moreover, from a viewpoint of maintaining favorable film formability, 50 mass% or less is preferable with respect to the total mass of the organic electronic material, 30 mass% or less is more preferable, and 20 mass% or less is still more preferable.

<Ink composition>
According to one embodiment, the ink composition contains the organic electronic 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. Organic solvents include alcohols such as methanol, ethanol and isopropyl alcohol; alkanes such as pentane, hexane and octane; cyclic alkanes such as cyclohexane; aromatic hydrocarbons such as benzene, toluene, xylene, mesitylene, tetralin and diphenylmethane; ethylene glycol Aliphatic ethers such as dimethyl ether, ethylene glycol diethyl ether, propylene glycol-1-monomethyl ether acetate; 1,2-dimethoxybenzene, 1,3-dimethoxybenzene, anisole, phenetole, 2-methoxytoluene, 3-methoxytoluene, Aromatic ethers such as 4-methoxytoluene, 2,3-dimethylanisole, 2,4-dimethylanisole; ethyl acetate, n-butyl acetate, ethyl lactate, n-butyl lactate Aliphatic esters such as phenyl acetate, phenyl propionate, methyl benzoate, ethyl benzoate, propyl benzoate and n-butyl benzoate; N, N-dimethylformamide, N, N-dimethylacetamide, etc. Amide solvents; dimethyl sulfoxide, 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.

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

[Additive]
The ink composition may further contain an additive as an optional component. Examples of additives include polymerization inhibitors, stabilizers, thickeners, gelling agents, flame retardants, antioxidants, antioxidants, oxidizing agents, reducing agents, surface modifiers, emulsifiers, antifoaming agents, Examples thereof include a dispersant and a surfactant.

[Content]
The content of the solvent in the ink composition can be determined in consideration of application to various coating methods. For example, the content of the solvent is preferably such that the ratio of the charge transporting polymer to the solvent is 0.1% by mass or more, more preferably 0.2% by mass or more, and 0.5% by mass or more. More preferred is an amount of 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 even more preferably 10% by mass or less. .

<Organic layer>
According to one embodiment, the organic layer is a layer formed using the organic electronic material or ink composition. The organic layer exhibits good charge transport properties. By using the ink composition, the organic layer can be satisfactorily and easily formed by a coating method. Examples of the coating method include spin coating method; casting method; dipping method; letterpress printing, intaglio printing, offset printing, planographic printing, letterpress inversion offset printing, screen printing, gravure printing and other plate printing methods; ink jet method, etc. A known method such as a plateless printing method may be used. When the organic layer is formed by a coating method, the organic layer (coating layer) obtained after the coating may be dried using a hot plate or an oven to remove the solvent.

When the charge transporting polymer has a polymerizable functional group, the solubility of the organic layer can be changed by proceeding the polymerization reaction of the charge transporting polymer by light irradiation, heat treatment or the like. By laminating organic layers with different solubility, it is possible to easily increase the number of organic electronics elements. For the method for forming the organic layer, for example, the description of WO 2010/140553 can be referred to.

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

<Organic electronics elements>
According to one embodiment, the organic electronics element has at least one said organic layer. Examples of the organic electronics element include an organic EL element, an organic photoelectric conversion element, and an organic transistor. The organic electronic element preferably has a structure in which an organic layer is disposed between at least a pair of electrodes.

<Organic electroluminescence device (organic EL device)>
According to one embodiment, the organic EL device has at least one organic layer. The organic EL element usually includes a light emitting layer, an anode, a cathode, and a substrate, and other functional layers such as a hole injection layer, an electron injection layer, a hole transport layer, and an electron transport layer are provided as necessary. I have. Each layer may be formed by a vapor deposition method or a coating method. The organic EL element preferably has the organic layer as a light emitting layer or other functional layer, more preferably as another functional layer, and more preferably as at least one of a hole injection layer and a hole transport layer. Have.

FIG. 1 is a schematic cross-sectional view showing an embodiment of an organic EL element. The organic EL element of FIG. 1 is an element having a multilayer structure, and includes 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. In this order.

[Light emitting layer]
As a material used for the light emitting layer, a light emitting material such as a low molecular compound, a polymer, or a dendrimer can be used. A polymer is preferable because it has high solubility in a solvent and is suitable for a coating method. Examples of the light emitting material include a fluorescent material, a phosphorescent material, a thermally activated delayed fluorescent material (TADF), and the like.

Fluorescent materials such as perylene, coumarin, rubrene, quinacridone, stilbene, dyes for dye lasers, aluminum complexes, and derivatives thereof; polyfluorene, polyphenylene, polyphenylene vinylene, polyvinyl carbazole, fluorene-benzothiadiazole copolymer , Fluorene-triphenylamine copolymers, polymers thereof such as derivatives thereof, and mixtures thereof.

As the phosphorescent material, a metal complex containing a metal such as Ir or Pt can be used. Examples of the Ir complex include FIr (pic) that emits blue light (iridium (III) bis [(4,6-difluorophenyl) -pyridinate-N, C ² ] picolinate), Ir (ppy) ₃ that emits green light. (Factris (2-phenylpyridine) iridium), which 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-phenylisoquinoline) iridium) and the like. Examples of the Pt complex include PtOEP (2, 3, 7, 8, 12, 13, 17, 18-octaethyl-21H, 23H-formin platinum) that emits red light.

In the case where the light emitting layer contains a phosphorescent material, it is preferable to further contain a host material in addition to the phosphorescent material. As the host material, a low molecular compound, a polymer, or a dendrimer can be used. Examples of the low molecular weight compound include CBP (4,4′-bis (9H-carbazol-9-yl) biphenyl), mCP (1,3-bis (9-carbazolyl) benzene), CDBP (4,4′- Examples of the polymer such as bis (carbazol-9-yl) -2,2′-dimethylbiphenyl) and derivatives thereof include the organic electronic materials, polyvinylcarbazole, polyphenylene, polyfluorene, and derivatives thereof.

Examples of the thermally active delayed fluorescent material include PIC-TRZ (2-biphenyl-4,6-bis (12-phenylindolo [2,3-a] carbazol-11-yl) -1,3,5-triazine), CC2TA (2,4-bis {3- (9H-carbazol-9-yl) -9H-carbazol-9-yl} -6-phenyl-1,3,5-triazine), CZ-PS (9,9 ' -(4,4'-sulfonylbis (4,1-phenylene)) bis (3,6-di-tert-butyl-9H-carbazole)), 4CzPN (3,4,5,6-tetra (9H-carbazol- 9-yl) phthalonitrile), HAP-3TPA (4,4 ', 4' '-(1,3,3a1,4,6,7,9-heptaazaphenalene-2,5,8-triyl) tris (N, N -bis (4- (tert-butyl) phenyl) aniline)) and the like.

[Hole injection layer, hole transport layer]
The organic layer is preferably used as at least one of a hole injection layer and a hole transport layer. As described above, these layers can be easily formed by using an ink composition containing an organic electronic material.

When the organic EL element has the organic layer as a hole injection layer and further has a hole transport layer, a known material can be used for the hole transport layer. Moreover, when an organic EL element has the said organic layer as a positive hole transport layer and also has a positive hole injection layer, a well-known material can be used for a positive hole injection layer. Known materials include, for example, aromatic amine compounds (eg, aromatic diamines such as N, N′-di (naphthalen-1-yl) -N, N′-diphenyl-benzidine (α-NPD)), phthalocyanines And thiophene compounds (for example, poly (3,4-ethylenedioxythiophene): thiophene conductive polymer such as poly (4-styrenesulfonate) (PEDOT: PSS)), and the like.

In the case where the hole transport layer is an organic layer whose solubility is changed, it is possible to easily form a light emitting layer on the upper layer using an ink composition. In this case, the polymerization initiator may be contained in the organic layer that is the hole transport layer, or may be contained in the organic layer under the hole transport layer.

[Electron transport layer, electron injection layer]
Examples of materials used for the electron transport layer and the electron injection layer include phenanthroline derivatives, bipyridine derivatives, nitro-substituted fluorene derivatives, diphenylquinone derivatives, thiopyran dioxide derivatives, condensed ring tetracarboxylic anhydrides such as naphthalene and perylene, carbodiimides, and the like. Fluorenylidenemethane derivatives, anthraquinodimethane and anthrone derivatives, oxadiazole derivatives, thiadiazole derivatives, benzimidazole derivatives, quinoxaline derivatives, aluminum complexes, and the like. The organic electronic 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, and CsF is used.

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

[substrate]
As the substrate, glass, plastic or the like can be used. The substrate is preferably transparent and preferably has flexibility. Quartz glass, resin film and the like are preferably used.

As the resin film, a light transmissive resin film is preferable. Examples of the resin film include polyethylene terephthalate, polyethylene naphthalate, polyethersulfone, polyetherimide, polyetheretherketone, polyphenylene sulfide, polyarylate, polyimide, polycarbonate, cellulose triacetate, and cellulose acetate propionate. Can be mentioned.

In the case of using a resin film, an inorganic substance such as silicon oxide or silicon nitride may be coated on the resin film in order to suppress permeation of water vapor, oxygen and the like.

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

[Luminescent 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 devices such as home lighting, interior lighting, a clock, or a liquid crystal backlight.

As a method of forming a white organic EL element, a method of simultaneously emitting a plurality of emission colors using a plurality of light emitting materials and mixing the colors can be used. A combination of a plurality of emission colors is not particularly limited. A combination containing three emission maximum wavelengths of blue, green and red, a combination containing two emission maximum wavelengths such as blue and yellow, yellow green and orange, etc. Is mentioned. The emission color can be controlled by adjusting the type and amount of the light emitting material.

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

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

<Example of Embodiment>
Examples of preferred embodiments of the present invention are given below. Embodiments of the present invention are not limited to the following examples.

[1] An organic electronic material containing a charge transporting polymer or oligomer having a branched structure and having a structural unit including a partial structure represented by the following formula (1).

[2] The charge transporting polymer or oligomer further has a structural unit having a hole transporting property,
The structural unit having hole transportability is a group consisting of a substituted or unsubstituted aromatic amine structure, a substituted or unsubstituted carbazole structure, a substituted or unsubstituted thiophene structure, and a substituted or unsubstituted fluorene structure. The organic electronic material according to [1], including a structural unit including at least one selected partial structure.
[3] A co-polymer of a monomer mixture in which the charge transporting polymer or oligomer includes a monomer having a structural unit including the partial structure represented by the formula (1) and a monomer having a structural unit having a hole transporting property. The organic electronic material according to [1] or [2], which is a polymer.

[4] The charge transporting polymer or oligomer has a trivalent or higher valent structural unit, a divalent structural unit, and a monovalent structural unit, and the divalent structural unit is represented by the formula (1). The organic electronic material according to any one of [1] to [3], comprising a structural unit including a partial structure represented by the formula:
[5] The charge transporting polymer or oligomer has at least a trivalent or higher structural unit and a monovalent structural unit, and the trivalent or higher structural unit is a partial structure represented by the formula (1). The organic electronic material according to any one of the above [1] to [4], comprising a structural unit containing
[6] The charge transporting polymer or oligomer has at least a trivalent or higher valent structural unit and a monovalent structural unit, and the monovalent structural unit is a partial structure represented by the formula (1). The organic electronic material according to any one of [1] to [5], including a structural unit.

[7] The organic electronic material according to any one of [1] to [6], wherein the charge transporting polymer or oligomer further has a polymerizable functional group.
[8] The organic electronic material according to [7], further including a polymerization initiator.
[9] An ink composition comprising the organic electronic material according to any one of [1] to [8] and a solvent.
[10] An organic layer formed using the organic electronic material according to any one of [1] to [8] or the ink composition according to [9].

[11] An organic electronic device comprising at least one organic layer according to [10].
[12] An organic electroluminescence device comprising at least one organic layer according to [10].
[13] A display device comprising the organic electroluminescence device according to [12].
[14] An illumination device comprising the organic electroluminescence element according to [12].
[15] A display device comprising the illumination device according to [14] and a liquid crystal element as display means.

Hereinafter, the present invention will be described more specifically with reference to examples. The present invention is not limited to the following examples.

<Preparation of Pd catalyst>
In a glove box under a nitrogen atmosphere, tris (dibenzylideneacetone) dipalladium (73.2 mg, 80 μmol) was weighed into a sample tube at room temperature, 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 in 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 obtain a catalyst solution (hereinafter also referred to as “Pd catalyst solution”). In preparing the catalyst, all solvents were used after degassing with nitrogen bubbles for more than 30 minutes.

<Synthesis of Charge Transporting Polymer 1>
In a three-necked round bottom flask, the following monomer L-1 (5.0 mmol), the following monomer B-1 (2.0 mmol), the following monomer T-1 (2.0 mmol), the following monomer T-2 (2.0 mmol), And anisole (20 mL) were added, and the Pd catalyst solution (7.5 mL) was further added. After stirring for 30 minutes, 10% tetraethylammonium hydroxide aqueous solution (20 mL) was added. All solvents were used after being degassed with nitrogen bubbles for more than 30 minutes. The resulting mixture was heated to reflux for 2 hours. All the operations so far 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 resulting precipitate was collected by suction filtration and washed with methanol-water (9: 1). The resulting precipitate was dissolved in toluene and reprecipitated from methanol. The resulting precipitate was collected by suction filtration, dissolved in toluene, and a metal adsorbent (“Triphenylphosphine, polymer-bound styrene-divinylbenzene polymer” manufactured by Strem Chemicals, 200 mg for 100 mg of the precipitate) was added. Stir overnight. After completion of the stirring, the metal adsorbent and insoluble matter were removed by filtration, 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 1.

The number average molecular weight of the obtained charge transporting polymer 1 was 5,600, and the weight average molecular weight was 40,200. The charge transporting polymer 1 has a structural unit L-1, a structural unit B-1, a structural unit T-1, and a structural unit T-2, and the ratio (molar ratio) of each structural unit is 45.5. %, 18.2%, 18.2%, and 18.2%.

The number average molecular weight and the weight average molecular weight were measured by GPC (polystyrene conversion) using tetrahydrofuran (THF) as an eluent. The measurement conditions are as follows.
Liquid feed pump: L-6050 Hitachi High-Technologies Corporation UV-Vis detector: L-3000 Hitachi High-Technologies Corporation Detection wavelength: 254 nm
Column: Gelpack (registered trademark) GL-A160S / GL-A150S Hitachi Chemical Co., Ltd. Eluent: THF (for HPLC, without stabilizer) Wako Pure Chemical Industries, Ltd. Flow rate: 1 mL / min
Column temperature: Room temperature (25 ° C)
Molecular weight reference material: Standard polystyrene (PStQuick B / C / D) Tosoh Corporation

<Synthesis of charge transporting polymer 2>
In a three-necked round bottom flask, the monomer L-1 (5.0 mmol), the monomer B-1 (1.8 mmol), the following monomer B-2 (0.2 mmol), the monomer T-1 (2.0 mmol), The following monomer T-3 (2.0 mmol) and anisole (20 mL) were added, and the Pd catalyst solution (7.5 mL) was further added. Thereafter, the charge transporting polymer 2 was synthesized in the same manner as the synthesis of the charge transporting polymer 1.

The number average molecular weight of the obtained charge transporting polymer 2 was 9,400, and the weight average molecular weight was 28,100. The charge transporting polymer 2 has a structural unit L-1, a structural unit B-1, a structural unit B-2, a structural unit T-1, and a structural unit T-3, and the ratio (molar ratio) of each structural unit. ) Were 45.5%, 16.4%, 1.8%, 18.2%, and 18.2%.

<Synthesis of charge transporting polymer 3>
In a three-necked round bottom flask, the monomer L-1 (5.0 mmol), the monomer B-1 (1.0 mmol), the monomer B-2 (1.0 mmol), the monomer T-1 (2.0 mmol), The monomer T-3 (2.0 mmol) and anisole (20 mL) were added, and the Pd catalyst solution (7.5 mL) was further added. Thereafter, the charge transporting polymer 3 was synthesized in the same manner as the synthesis of the charge transporting polymer 1.

The number average molecular weight of the obtained charge transporting polymer 3 was 11,000, and the weight average molecular weight was 32,000. The charge transporting polymer 3 has a structural unit L-1, a structural unit B-1, a structural unit B-2, a structural unit T-1, and a structural unit T-3, and the ratio (molar ratio) of each structural unit. ) Were 45.5%, 9.1%, 9.1%, 18.2%, and 18.2%.

<Synthesis of Charge Transporting Polymer 4>
In a three-necked round bottom flask, the monomer L-1 (5.0 mmol), the monomer B-2 (2.0 mmol), the monomer T-1 (2.0 mmol), the monomer T-3 (2.0 mmol), And anisole (20 mL) were added, and the Pd catalyst solution (7.5 mL) was further added. Thereafter, the charge transporting polymer 4 was synthesized in the same manner as the charge transporting polymer 1 was synthesized.

The number average molecular weight of the obtained charge transporting polymer 4 was 10,200, and the weight average molecular weight was 31,700. The charge transporting polymer 4 has a structural unit L-1, a structural unit B-2, a structural unit T-1, and a structural unit T-3, and the ratio (molar ratio) of each structural unit is 45.5. %, 18.2%, 18.2%, and 18.2%.

<Synthesis of charge transporting polymer 5>
In a three-necked round bottom flask, the following monomer L-2 (5.0 mmol), monomer B-1 (2.0 mmol), monomer T-1 (2.0 mmol), monomer T-3 (2.0 mmol), And anisole (20 mL) were added, and the Pd catalyst solution (7.5 mL) was further added. Thereafter, the charge transporting polymer 5 was synthesized in the same manner as the charge transporting polymer 1 was synthesized.

The number average molecular weight of the obtained charge transporting polymer 5 was 12,100, and the weight average molecular weight was 45,000. The charge transporting polymer 5 has a structural unit L-2, a structural unit B-1, a structural unit T-1, and a structural unit T-3, and the ratio (molar ratio) of each structural unit is 45.5. %, 18.2%, 18.2%, and 18.2%.

(Synthesis of charge transporting polymer 6)
In a three-necked round bottom flask, the monomer L-1 (5.0 mmol), the monomer B-1 (2.0 mmol), the monomer T-1 (2.0 mmol), the monomer T-3 (2.0 mmol), And anisole (20 mL) were added, and the Pd catalyst solution (7.5 mL) was further added. Thereafter, the charge transporting polymer 6 was synthesized in the same manner as the charge transporting polymer 1 was synthesized.

The number average molecular weight of the obtained charge transporting polymer 6 was 10,000, and the weight average molecular weight was 47,600. The charge transporting polymer 6 has a structural unit L-1, a structural unit B-1, a structural unit T-1, and a structural unit T-3, and the ratio (molar ratio) of each structural unit is 45.5. %, 18.2%, 18.2%, and 18.2%.

<Synthesis of charge transporting polymer 7>
In a three-necked round bottom flask, the following monomer L-3 (5.0 mmol), monomer B-1 (2.0 mmol), monomer T-1 (2.0 mmol), monomer T-3 (2.0 mmol), And anisole (20 mL) were added, and the Pd catalyst solution (7.5 mL) was further added. Thereafter, the charge transporting polymer 7 was synthesized in the same manner as the charge transporting polymer 1 was synthesized.

The number average molecular weight of the obtained charge transporting polymer 7 was 10,300, and the weight average molecular weight was 32,600. The charge transporting polymer 7 has a structural unit L-3, a structural unit B-1, a structural unit T-1, and a structural unit T-3, and the ratio (molar ratio) of each structural unit is 45.5. %, 18.2%, 18.2%, and 18.2%.

<Fabrication of charge transportability evaluation element>
Under an air atmosphere, each charge transporting polymer (10.0 mg), the following electron-accepting compound 1 (0.5 mg), and toluene (1.5 mL) were mixed to prepare an ink composition. The ink composition was spin-coated on a glass substrate patterned with ITO at a width of 1.6 mm at a rotation speed of 3,000 min ⁻¹ , and then cured by heating on a hot plate at 210 ° C. for 30 minutes to form an organic layer ( 100 nm).

The substrate having the organic layer was transferred into a vacuum vapor deposition machine, and aluminum was deposited on the organic layer by a vapor deposition method (100 nm), followed by sealing treatment to produce a charge transportability evaluation element.

A voltage was applied using the ITO of the charge transportability evaluation element as an anode and aluminum as a cathode. Table 1 shows current densities (A / cm ³ ) when voltages of 0.1 V and 1.5 V were applied, respectively.

As shown in Table 1, according to the organic electronic material which is an embodiment of the present invention, an organic layer showing good charge transportability was obtained.

As mentioned above, the effect of the embodiment of the present invention was shown using the example. In addition to the organic electronic materials used in the examples, the organic layer containing the charge transporting polymer having the structural unit (1) described above can be used to obtain an organic layer exhibiting good charge transportability. Is possible. By using an organic layer exhibiting good charge transportability, it is possible to obtain an organic electronics element with a low driving voltage.

DESCRIPTION OF SYMBOLS 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

An organic electronic material comprising a charge transporting polymer or oligomer having a branched structure and having a structural unit including a partial structure represented by the following formula (1).

(In the formula (1), each Ra independently represents a hydrogen atom or a substituent. Each Rb independently represents a hydrogen atom, a substituent, or a bonding site with another structure, and One is the binding site with other structures.)
The charge transporting polymer or oligomer further has a structural unit having a hole transporting property,
The structural unit having hole transportability is a group consisting of a substituted or unsubstituted aromatic amine structure, a substituted or unsubstituted carbazole structure, a substituted or unsubstituted thiophene structure, and a substituted or unsubstituted fluorene structure. The organic electronic material of Claim 1 containing the structural unit containing at least 1 type of partial structure chosen.
The charge transporting polymer or oligomer is a copolymer of a monomer mixture containing a monomer having a structural unit including the partial structure represented by the formula (1) and a monomer having a structural unit having a hole transporting property. The organic electronic material according to claim 1 or 2.
The charge transporting polymer or oligomer has a trivalent or higher valent structural unit, a divalent structural unit, and a monovalent structural unit, and the divalent structural unit is represented by the formula (1). The organic electronic material according to any one of claims 1 to 3, comprising a structural unit including a partial structure.
The charge transporting polymer or oligomer has at least a trivalent or higher structural unit and a monovalent structural unit, and the trivalent or higher structural unit includes a partial structure represented by the formula (1). The organic electronic material according to any one of claims 1 to 4, comprising a unit.
The charge transporting polymer or oligomer has at least a trivalent or higher valent structural unit and a monovalent structural unit, and the monovalent structural unit includes a partial structure represented by the formula (1). The organic electronic material according to any one of claims 1 to 5, comprising
The organic electronic material according to any one of claims 1 to 6, wherein the charge transporting polymer or oligomer further has a polymerizable functional group.
The organic electronic material according to claim 7, further comprising a polymerization initiator.
An ink composition comprising the organic electronic material according to any one of claims 1 to 8 and a solvent.
An organic layer formed using the organic electronic material according to any one of claims 1 to 8 or the ink composition according to claim 9.
An organic electronic device comprising at least one organic layer according to claim 10.
An organic electroluminescence device comprising at least one organic layer according to claim 10.
A display element comprising the organic electroluminescence element according to claim 12.
An illumination device comprising the organic electroluminescence element according to claim 12.
A display device comprising the illumination device according to claim 14 and a liquid crystal element as display means.