WO2019059331A1

WO2019059331A1 - Charge transport compound, composition containing charge transport compound, and organic electroluminescent element using said composition

Info

Publication number: WO2019059331A1
Application number: PCT/JP2018/034963
Authority: WO
Inventors: 五郎丸　英貴; 祥匡坂東; 英司小松; 延軍李; 友和梅基; 逸美西尾
Original assignee: 三菱ケミカル株式会社
Priority date: 2017-09-22
Filing date: 2018-09-21
Publication date: 2019-03-28
Also published as: KR20200054979A; JPWO2019059331A1; KR20230147770A; CN111094385A; TWI787355B; JP7310605B2; CN111094385B; CN118459730A; TW201925266A; KR102591741B1

Abstract

A composition which contains a charge transport compound that has a structural unit represented by formula (1) and a compound that has a structural unit represented by formula (5), formula (6) or formula (7). (In formula (1), X1 represents a group represented by formula (2).)

Description

Charge-transporting compound, composition containing charge-transporting compound, and organic electroluminescent device using the composition

The present invention relates to a charge transporting compound, a composition containing the charge transporting compound, and an organic electroluminescent device using the composition. In particular, the present invention relates to an excellent charge transporting compound and composition capable of obtaining an organic electroluminescent device which can be driven at a low voltage.

In recent years, development of an electroluminescent element (organic electroluminescent element) using an organic material instead of an inorganic material such as ZnS as an electroluminescent (EL) element has been performed. In the organic electroluminescent device, the high luminous efficiency is one of the important factors, but the luminous efficiency is the luminescence composed of the hole transport layer containing the aromatic amine compound and the aluminum complex of 8-hydroxyquinoline The organic electroluminescent device provided with a layer is greatly improved.

Examples of the method of forming the organic layer in the organic electroluminescent device include a vacuum evaporation method and a wet film formation method. Since vacuum deposition is easy to laminate, it has the advantages of improved charge injection from the anode and / or cathode and easy containment of the light emitting layer of excitons. On the other hand, the wet film formation method does not require a vacuum process, is easy to increase the area, and easily uses a plurality of materials having a variety of functions by using a coating solution that has a variety of functions. There are advantages such as the ability to form a layer containing the material of

However, the wet film formation method is difficult to be laminated, and thus the driving stability is inferior to that of a device by a vacuum evaporation method, and at present it has not reached a practical level except for a part.

Then, in order to perform lamination by a wet film formation method, a charge transporting polymer having a crosslinkable group is desired, and its development has been carried out. For example, Patent Documents 1 to 6 disclose organic electroluminescent devices which contain a polymer having a specific repeating unit and are laminated by a wet film forming method.

International Publication No. 2009/123269 International Publication No. 2013/191088 JP, 2013-045986, A WO 2010/097156 JP, 2010-171189, A JP, 2010-215886, A

However, the inventors have found that the polymers described in the above patent documents, their cross-linking groups, compositions containing the polymers, etc. have the following problems.

In Patent Document 1-2, benzocyclobutene and a styrene crosslinking group are proposed as a crosslinking group of a polymer. However, the benzocyclobutene crosslinking group inhibits charge transfer by a side reaction during crosslinking. For this reason, there is a problem that the driving voltage of the organic electroluminescent device using the polymer having a benzocyclobutene crosslinking group is high.
As for the styrene crosslinking group, the HECK reaction proceeds as a side reaction during the reaction using a Pd catalyst at the time of polymer synthesis. Therefore, there is a problem that the yield of the polymer is low and the production thereof is expensive.

In addition, the polymer having a styrene crosslinking group and oxetane (cyclic ether) crosslinking group described in Patent Literature 2-3 has a high reactivity of the crosslinking group and thus the storage stability is reduced, particularly by mixing with an ionic compound. Storage is disadvantageous in that storage stability is further reduced.

Patent Document 4 proposes a polymer having a methylstyrene crosslinking group. Since these cross-linking groups use a structure in which the substituent of the polymer side chain and the polymer main chain are broken, or a fused ring of anthracene or the like which is difficult to carry a positive charge, an organic electric field using this There is a drawback that the drive voltage of the light emitting element is increased.

Patent Document 5 discloses an arylamine polymer used in a light emitting layer and a polymer having a stilbene structure (styrene structure substituted with a benzene ring) in a side chain, but as a compound for a hole injecting and transporting layer It is not used, nor is it described that the stilbene is crosslinkable.

Patent Document 6 discloses a polymer having both a double bond-based crosslinking group and a benzocyclobutene-based crosslinking group in one polymer. However, it is necessary to further extend the life of the device.

The present invention has been made in view of the above-mentioned problems, and an object thereof is to provide an organic electroluminescent device which can be driven at a low voltage. Another object of the present invention is to provide an organic electroluminescent device which can be driven with high efficiency and long life. Another object of the present invention is to provide a charge transportable compound and a composition thereof which have a high yield at the time of synthesis and which are excellent in storage stability.

As a result of intensive investigations, the present inventors have found that the above problems can be effectively solved by using a charge transporting compound having a specific structure, a specific charge transporting compound and a composition containing the compound.

The gist of the present invention is as follows.

[1] A charge transporting compound having a structural unit represented by the following formula (1), and a compound having a structural unit represented by the following formula (5), formula (6) or formula (7), Composition.

[In Formula (1), X ¹ is a group represented by the following Formula (2). ]

[In the formula (2),
* Represents a binding site to N in formula (1),
Y ¹ is a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms, a substituted or unsubstituted aminoarylene group, a chalcogen atom, a carbonyl group, or a substituted or unsubstituted 1 to 20 carbon atoms Indicates an alkylene group.
R ¹¹ represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms, or a substituted or unsubstituted arylamino group.
R ¹² represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms or a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms.
The substituent of R ¹¹ and R ¹² may combine to form a ring.
k is an integer of 1 or more and 10 or less, and Y ¹ when k is 2 or more may be the same or different.
m is 1 or 2 and R ¹² when m is 2 may be the same or different.
n is 0 or 1. ]

[In the formula (5),
* Represents a binding site,
E ¹ , E ² and E ³ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms, a fluorine Represents an atom or a substituted carbonyl group.
However, E ² and E ³ are not simultaneously hydrogen atoms. ]

[In the formula (6),
* Represents a binding site,
R ³¹ is a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms , A substituted or unsubstituted alkyloxy group having 1 to 10 carbon atoms, a fluorine atom or a substituted carbonyl group,
j represents an integer of 0 or more and 5 or less, and R ³¹ when j is 2 or more may be the same or different. ]

[In the formula (7),
* Represents a binding site,
R ⁴¹ is a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms , A fluorine atom or a substituted carbonyl group,
y represents an integer of 0 or more and 5 or less, and R ⁴¹ when y is 2 or more may be the same or different. ]

[2] The composition according to [1], wherein R ^{12 in the} formula (2) is an alkyl group having 1 to 20 carbon atoms.

[3] The composition according to [1] or [2], wherein n in formula (2) is 0.

[4] The composition according to any one of [1] to [3], wherein the charge transporting compound contains a structural unit represented by the following formula (3).

[In the formula (3),
Each of Ar ²¹ and Ar ²² independently represents a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms.
R ²¹ represents a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms, or a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms.
a is an integer of 1 or more and 5 or less, and when R ²¹ is 2 or more, Ar ²¹ may be the same or different.
b is an integer of 0 or more and 5 or less, and R ²¹ when b is 2 or more may be the same or different. ]

[5] Any one of [1] to [4], wherein the 5% mass loss start temperature of the compound having a structural unit represented by the above formula (5), formula (6) or formula (7) is 300 ° C. or less The composition according to claim 1.

[6] according to any one of [1] to [5], wherein the polymerization initiation temperature of the compound having a structural unit represented by the formula (5), formula (6) or formula (7) is 80 ° C. or higher Composition of

[7] The compound of [1] to [6], wherein the compound having a structural unit represented by the formula (5), the formula (6) or the formula (7) is a compound represented by the following formula (4) The composition as described in any one.

[In the formula (4),
Y ⁻ represents an anion and Z ⁺ represents a cation, and a pair of Y ⁻ and Z ⁺ represents a compound.
L ¹ represents a single bond, a chalcogen atom, a carbonyl group, a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms, or an substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms;
L ¹ is bound to Y ^- or Z ⁺ ,
L ² is represented by the formula (5), the formula (6) or the formula (7).
d and e are each independently an integer of 1 to 5, and when d is 2 or more, L ¹ may be the same or different, and when e is 2 or more, L ² may be the same or different May be
f is an integer of 1 or more and 4 or less, and when f is 2 or more, L ¹ , L ² , d and e in the formula (4) may be the same or different, and when f is 2 or more, e is an integer of 1 or more and 5 or less, and at least one e is 1 or more. ]

[8] The composition according to any one of [1] to [7], which is used for a hole injection layer and / or a hole transport layer of an organic electroluminescent device.

[9] An organic electroluminescent device having a light emitting layer, a hole injection layer and / or a hole transport layer between an anode and a cathode, wherein the hole injection layer and / or the hole transport layer is [1] The organic electroluminescent element which is a layer formed by apply | coating and drying the composition in any one of [8].

[10] An organic EL display device using the organic electroluminescent device according to [9].

[11] An organic EL illumination using the organic electroluminescent device according to [9].

[12] A compound having a structural unit represented by the following formula (5), formula (6) or formula (7).

[13] A charge transporting compound containing a structural unit represented by the following formula (10).

Wherein (10), X ¹ 'is a group represented by the following formula (11). ]

[In the formula (11),
* Represents a binding site to N in formula (10),
Y ¹ ′ represents a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms, a chalcogen atom, a carbonyl group, or a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms.
R ¹¹ ′ represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms, or a substituted or unsubstituted arylamino group.
R ¹² ′ represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms.
The substituent of R ¹¹ ′ and R ¹² ′ may combine to form a ring.
k 'is an integer of 1 or more and 10 or less, Y ¹ ' when k 'is 2 or more may be the same or different, R ¹² ' is an aromatic hydrocarbon group, and C = C type When Y ¹ ′ directly bonded to a double bond is a benzene ring, k ′ is 2 or more.
m'is 1 or 2, m'is R ¹² in case of 2 'may be the same or different.
n 'is 0 or 1. ]

According to the present invention, it is possible to provide an organic electroluminescent device which can be driven at a low voltage by a charge transporting compound excellent in yield efficiency at the time of synthesis. In addition, the composition containing the charge transporting compound of the present invention is excellent in storage stability, and a coated film obtained by using the composition is excellent in stability.

Fig. 1a to FIG. 1 b is a cross-sectional view schematically showing an example of the configuration of an organic electroluminescent device according to an embodiment of the present invention.

The embodiment of the present invention will be described in detail below, but the description of the constituent requirements described below is an example (representative example) of the embodiment of the present invention, and the present invention does not exceed the gist thereof. Not specified in the content of.
In the present specification, “mass” is synonymous with “weight”.
Also, "polymer", "polymer", "polymer" or "polymer compound" are synonymous unless otherwise noted.
Also, the circled plus (+) symbol in the formula represents a positive charge, which is indicated by "+" in the specification, and the circled minus (-) symbol in the formula is also a negative charge. In the specification, it is indicated by "-".
Moreover, having the substituent means that it may have at least one or more substituents.
In the present invention, polymerization or polymerization reaction means that two or more compounds are bonded to each other to form a compound having a molecular weight larger than that of the compound before the reaction. This includes so-called cross-linking reaction in which cross-linking groups of two or more compounds having cross-linking groups are combined with each other, in addition to so-called multi-monomer bonding to form a compound with high molecular weight.

[Composition Containing Charge Transportable Compound]
The composition of the present invention comprises a charge transporting compound containing a structural unit represented by the following formula (1) and a compound having a structural unit represented by the following formula (5), formula (6) or formula (7) It is characterized by including.
In addition, in this specification, the compound which has a structural unit represented by Formula (5), Formula (6), or Formula (7) may be represented as "the compound A."

[In Formula (1), X ¹ is a group represented by the following Formula (2). ]

The composition of the present invention is excellent in storage stability, and a coated film obtained using the composition is excellent in stability. In addition, the organic electroluminescent device obtained by using the composition can be driven at a low voltage.
The following can be considered as the reason why these effects can be obtained.

The structural unit represented by Formula (1) can suppress the main chain distortion at the time of crosslinking, and at the same time, can suppress side reactions as much as possible. Therefore, the yield efficiency is high, and the composition containing the charge transporting compound is excellent in storage stability.
The side reaction is expected to occur at the charge transport site of the polymer during crosslinking of the polymer having a benzocyclobutene crosslinking group, and the charge transporting compound having a crosslinking group of the present invention suppresses this side reaction. Be done.
On the other hand, in the charge transporting compound of the present invention, the following effects are considered to be obtained by the steric hindrance of the substituent substituted at both ends of the vinyl group.
1) Reduction of side reaction during polymer synthesis using Pd coupling 2) Suppression of polymerization reaction in the presence of a polymerization initiator And, on the other hand, since the polymerization reactivity at high temperature is maintained, the wet formation The film method enables easy lamination.

The composition of the present invention preferably further includes a solvent in addition to the charge transporting compound containing the structure represented by Formula (1) and Compound A for wet film formation, and is represented by Formula (1) It is preferable that the charge transporting compound having a structure and the compound A be dissolved in a solvent. The composition of the present invention may contain a polymerization initiator, a charge transporting compound not including the structure represented by the formula (1), various additives, and the like. The type and content of these components may be appropriately selected according to the application and purpose.

[Charge Transportable Compound]
The charge transporting compound of the present invention contains a structural unit represented by the following formula (1). The organic electroluminescent element obtained using the charge transporting compound containing the structural unit represented by Formula (1) can be driven at a low voltage. In addition, the charge transporting compound of the present invention has high yield efficiency, and the composition containing the charge transporting compound is excellent in storage stability.

The following can be considered as the reason why these effects can be obtained.
In the structural unit represented by the formula (1), an arylamine having a high mobility of positive charge is a main chain or a main skeleton, and has a crosslinking group represented by the formula (2). A C = C type double bond (vinyl group structure), which is a crosslinking site, is disposed from an atom via a substituent (linking group). When Y ¹ to which the double bond is directly bonded is a benzene ring (phenylene group), it is a styrene configuration having R ¹¹ and R ¹² as a substituent. When the structural unit represented by the formula (1) is a polymer compound, since the crosslinking group is linked from the main chain of arylamine via the linking group, the main chain distortion of arylamine during crosslinking is suppressed. At the same time, it became possible to suppress side reactions as much as possible. Therefore, the yield efficiency is high, and the composition containing the charge transporting compound is excellent in storage stability.
The side reaction is expected to occur at the charge transport site of the polymer compound upon crosslinking of the polymer compound having a benzocyclobutene crosslinking group, and the charge transport compound having a crosslinking group of the present invention is not limited to this. Side reactions are suppressed. Accordingly, the charge transporting compound of the present invention is preferably a polymer compound, and more preferably having only the group represented by Formula (2) as a crosslinking group.
On the other hand, in the charge transporting compound of the present invention, it is considered that the following effects can be obtained by the steric hindrance of the substituent substituted at both ends or at the end of the vinyl group.
1) Reduction of side reaction during polymer synthesis using Pd coupling 2) Suppression of polymerization reaction in the presence of a polymerization initiator And, on the other hand, since the polymerization reactivity at high temperature is maintained, the wet formation The film method enables easy lamination.

[In Formula (1), X ¹ is a group represented by the following Formula (2). ]

In the composition of the present invention, the content of the charge transporting compound including the structure represented by Formula (1) is not particularly limited. The compound represented by the formula (1) relative to the total amount of the charge transporting compound containing the structure represented by the formula (1), the compound A and the charge transporting compound not containing the structure represented by the formula (1) The content of the charge transporting compound having a structure is preferably 99.9% by mass or less, more preferably 99% by mass or less, and still more preferably 95% by mass or less. Moreover, it is preferable that it is 50 mass% or more, and it is more preferable that it is 70 mass% or more. Within these ranges, the drive voltage is suppressed, and the effect of improving the stability of the coating film tends to be obtained. In the case where the composition of the present invention does not contain the charge transporting compound which does not contain the structure represented by the formula (1), the ratio of the content is the structure represented by the formula (1) And the content of the charge transporting compound including the structure represented by the formula (1) with respect to the compound A.

<Formula (1)>
The structural unit represented by Formula (1) is a structural unit which forms an arylamine structure. Among the arylamine structures, tertiary arylamine structures are preferred because of their high charge transportability and high stability during charge transport. Therefore, it is preferable that both ends of the nitrogen atom of Formula (1) are a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms.
The preferred structure of the substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms is the same as the substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms in Y 1 described later.

<Y ¹ >
Y ¹ represents a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms, a substituted or unsubstituted aminoarylene group, a chalcogen atom, a carbonyl group, or a substituted or unsubstituted alkylene group.
As the substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms, an aromatic hydrocarbon ring group and an aromatic heterocyclic group, or these aromatic hydrocarbon ring group and aromatic heterocyclic group are linked Represents a substituent of
Y ¹ is preferably a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms, a substituted or unsubstituted aminoarylene group, a chalcogen atom, or a substituted or unsubstituted alkylene group, and among them, 2 A substituted or unsubstituted aromatic ring group having 3 to 60 ring-forming atoms is preferable, and a substituted or unsubstituted aromatic hydrocarbon ring having 3 to 60 ring-forming atoms for increasing the stability of the heavy bond. Groups are more preferred.

(Substituent of Y ¹ )
When the aromatic ring group having 3 to 60 ring atoms, an aminoarylene group and an alkylene group of Y ¹ have a substituent, there is no particular limitation, and examples of the substituent include substituent group W described later. Be

(Substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms)
The number of ring-forming atoms of the substituted or unsubstituted aromatic ring group is 3 or more, preferably 5 or more, and more preferably 6 or more. Further, the number of ring-forming atoms is 60 or less, preferably 45 or less, and more preferably 30 or less. Within these ranges, the effect of compound stability tends to be obtained.

The aromatic ring group is preferably a single ring, a 2-6 condensed ring or a group in which two or more of these aromatic rings are linked. Specifically, the following may be mentioned.
Divalent derived from an aromatic hydrocarbon ring such as benzene ring, naphthalene ring, anthracene ring, phenanthrene ring, perylene ring, tetracene ring, pyrene ring, benzpyrene ring, chrysene ring, triphenylene ring, acenaphthene ring, fluoranthene ring or fluorene ring Group;
Furan ring, benzofuran ring, thiophene ring, benzothiophene ring, pyrrole ring, pyrazole ring, imidazole ring, oxadiazole ring, indole ring, carbazole ring, pyrroloimidazole ring, pyrrolopyrazole ring, pyrrolopyrrole ring, thienopyrrole ring, thienothiophene Ring, furopyrrole ring, furofuran ring, benzofuran ring, benzoisoxazole ring, benzisothiazole ring, benzimidazole ring, pyridine ring, pyrazine ring, pyridazine ring, pyrimidine ring, triazine ring, quinoline ring, isoquinoline ring, cinnoline ring, quinoxaline A divalent group derived from a heteroaromatic hydrocarbon ring such as a ring, a phenanthridine ring, a perimidine ring, a quinazoline ring, a quinazolinone ring or an azulene ring;
A divalent group derived from a compound formed by connecting an aromatic hydrocarbon ring group such as biphenyl, terphenyl, quaterphenyl and the like, and an aromatic heterocyclic group:

Among them, it is composed of a benzene ring, a naphthalene ring, a fluorene ring, a divalent group derived from a carbazole ring, and a bivalent group derived from biphenyl because the charge is delocalized efficiently and excellent in stability and heat resistance. Rings or groups selected from the group are more preferred. Particularly preferred is a benzene ring, a carbazole ring or a bivalent group derived from biphenyl.

(Substituted or unsubstituted aminoarylene group)
Examples of the substituted or unsubstituted aminoarylene group include triphenylamine, diphenylaminobiphenyl, bis (biphenyl) aniline, tris (biphenyl) amine, tetraphenylbenzidine, and divalent groups derived from diphenyl pyridylamine. Be
Among these, a divalent group derived from triphenylamine, diphenylaminobiphenyl, bis (biphenyl) aniline, tris (biphenyl) amine and tetraphenylbenzidine is preferable for the stability of the compound. Furthermore, divalent groups derived from triphenylamine, diphenylaminobiphenyl, bis (biphenyl) aniline and tris (biphenyl) amine are particularly preferable in terms of strong stability.
The carbon number of the aminoarylene group is also not particularly limited, but is preferably 15 or more, more preferably 18 or more. Moreover, Preferably it is 72 or less, More preferably, it is 50 or less. With these ranges, low voltage drive tends to be obtained.

(Chalcogen atom)
Examples of the chalcogen atom include an oxygen atom, a sulfur atom, a selenium atom, and a tellurium atom. Among these, oxygen atom and sulfur atom are preferable for the stability of the compound.

(Substituted or unsubstituted alkylene group having 1 to 20 carbon atoms)
The substituted or unsubstituted alkylene group having 1 to 20 carbon atoms is not particularly limited, and examples thereof include methylene, ethylene, propylene, butylene, hexylene, octylene and the like, and they may be linear, branched or cyclic. good.
The carbon number of the alkylene group is preferably 1 or more. The carbon number is preferably 20 or less, more preferably 10 or less. It is in the tendency which the effect of stabilization of a compound is acquired by being these ranges.

<K>
k is an integer of 1 or more and 10 or less. Preferably it is one or more, Preferably it is eight or less, More preferably, it is five or less. Within these ranges, the effect of the stability of the compound tends to be obtained.
In the case where k is 2 or more, Y ¹ may be the same or different.
When R ¹² is an aromatic hydrocarbon group and Y ¹ directly bonded to a C = C type double bond is a benzene ring (phenylene group), k is preferably 2 or more. The reason is that if an aromatic hydrocarbon (including a benzene ring) group is present on both sides of the C = C type double bond which reacts with the crosslinking group, the aromatic hydrocarbon structure is rigid and thus the strain of the polymer main chain at the time of crosslinking However, it is considered that when k is 2 or more and the crosslinking site is away from the polymer main chain, the strain is easily relaxed.
When k is 2 or more, the combination of a plurality of Y ¹ is not particularly limited, and examples thereof include a combination of an aromatic ring group and an aromatic ring group, an aromatic hydrocarbon ring group and a carbonyl group, and an alkylene group and a carbonyl group .

<R ¹¹ >
R ¹¹ represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms, or a substituted or unsubstituted arylamino group.
Among these, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms is preferable because the stability of the compound tends to be improved.

(A substituted or unsubstituted alkyl group of 1 to 20 carbon atoms with R ¹¹ )
The number of carbon atoms of the substituted or unsubstituted alkyl group having 1 to 20 carbon atoms which is R ¹¹ is not particularly limited, but is 1 or more and 20 or less, more preferably 10 or less. Within these ranges, the effect of the stability of the compound tends to be obtained.
Specific examples of the substituted or unsubstituted alkyl group having 1 to 20 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, a cyclohexyl group and an octyl group. good.
The alkyl group may have a substituent, and examples thereof include a substituent group W described later.

(R ¹¹ substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms)
The substituted or unsubstituted aromatic ring group having 3 to 60 ring forming atoms as R ¹¹ is a monovalent group derived from the aromatic ring having 3 to 60 ring forming atoms described above for Y ^1. And the substituent which it may have, the preferable range, the preferable form, the preferable reason, etc. are also synonymous.

(R ¹¹ substituted or unsubstituted arylamino group)
The carbon number of the substituted or unsubstituted arylamino group of R ¹¹ is not particularly limited, but is preferably 15 or more, more preferably 18 or more. Moreover, Preferably it is 72 or less, More preferably, it is 50 or less. With these ranges, driving at a low voltage tends to be possible.
The substituted or unsubstituted arylamino group is not particularly limited, and for example, a monovalent derived from triphenylamine, diphenylaminobiphenyl, bis (biphenyl) aniline, tris (biphenyl) amine, tetraphenylbenzidine, diphenylpyridylamine And the like. Among these, monovalent groups derived from triphenylamine, diphenylaminobiphenyl, bis (biphenyl) aniline, tris (biphenyl) amine and tetraphenylbenzidine are preferred for the reason of the stability of the compound. In addition, from the viewpoint of strong stability, monovalent groups derived from triphenylamine, diphenylaminobiphenyl, bis (biphenyl) aniline and tris (biphenyl) amine are particularly preferable.
When the arylamino group has a substituent, the substituent is not particularly limited, and examples thereof include Substituent Group W described later.

<R ¹² >
R ¹² represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms. Among these, since the crosslinking reactivity tends to be improved, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms or a monovalent group derived from an aromatic hydrocarbon ring is preferable, and the number of unsubstituted carbon atoms is preferred. An alkyl group of 1 or more and 20 or less is particularly preferable. The reason for this is that the film formed using the composition of the present invention is flexible when R ¹² is an alkyl group, and therefore the strain in the film is relaxed and the film is stable. Furthermore, when this film is used as a charge transport film, the effect of improving the charge transportability is expected. Moreover, since it is flexible, it is thought that it is easy to crosslink by heating.
The substituted or unsubstituted alkyl group having 1 to 20 carbon atoms which is R ^{12 and} the substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms have the substituted or unsubstituted carbon atoms mentioned in R ¹¹ It is synonymous with an alkyl group of 1 or more and 20 or less, and an aromatic ring group having 3 or more and 60 or less ring forming atoms which is substituted or unsubstituted, and may have a substituent, a preferable range, a preferable form, a preferable reason, etc. It is synonymous.

When the substituent of R ¹¹ and R ¹² combine to form a ring, examples of the ring include cyclohexene and the like.

<M>
m is 1 or 2; m is preferably 1, because the crosslinking reactivity tends to be improved.
R ¹² when m is 2 may be the same or different. When m is 2, the combination of the plurality of R ¹² is not particularly limited, and examples thereof include a combination of an alkyl group and an alkyl group, a combination of an alkyl group and an aromatic ring group, and the like.

<N>
n is 0 or 1. n being 0 is synonymous with n being 1 and R ¹¹ being a hydrogen atom. In order to reduce the steric hindrance of the double bond which is a crosslinking site, n is preferably 0.

<Combination of Y ¹ , R ¹¹ and R ¹² >
The combination of Y ¹ , R ¹¹ and R ¹² is not particularly limited, but Y ¹ is an aromatic hydrocarbon ring group, n is 0, R ¹¹ is a hydrogen atom, R ¹² is a combination of alkyl groups, and Y ¹ is derived from a benzene ring It is preferable that a combination of a divalent group of the above and an alkylene group, R ¹¹ be a hydrogen atom when n = 0, R ¹² be an alkyl group, or the like. With these combinations, the effect of improving the reactivity at the time of crosslinking tends to be obtained.

<Substituent group W>
Examples of the substituent group W include the following.
C 1 or more, 10 or less, preferably 8 or less alkyl groups such as methyl group and ethyl group; alkenyl groups having 2 or more and 11 or less carbon atoms such as vinyl group, preferably 5 or less; ethynyl group and the like And an alkynyl group having 2 or more and 11 or less, preferably 5 or less carbon atoms; an alkoxy group having 1 or more and 10 or less, preferably 6 or less carbon atoms such as a methoxy group and an ethoxy group; An aryloxy group having 4 or more, preferably 5 to 25, preferably 14 or less carbon atoms such as a pyridyloxy group; a carbon number of 2 to 11 or more, preferably a methoxycarbonyl group, an ethoxycarbonyl group or the like 7 or less alkoxycarbonyl groups; dialkylamino groups having a carbon number of 2 or more and 20 or less, preferably 12 or less, such as dimethylamino and diethylamino groups; The carbon number is usually 10 or more, preferably 12 or more, preferably 30 or less, preferably 22 or less, such as phenylamino group, ditolylamino group, N-carbazolyl group; 6 or more carbon atoms such as phenylmethylamino group Preferably, 7 or more and 25 or less, preferably 17 or less arylalkylamino groups; an acyl group having 2 or more and 10 or less, preferably 7 or less carbon atoms such as an acetyl group and a benzoyl group; A halogen atom having 1 to 8 carbon atoms, preferably 4 or less, such as a trifluoromethyl group; 1 to 10 carbon atoms, preferably 6 or less, such as a methylthio group or an ethylthio group An alkylthio group; a phenylthio group, a naphthylthio group, a pyridylthio group, etc., having 4 or more carbon atoms, preferably 5 to 25 carbon atoms, 14 or less arylthio group; a silyl group having a carbon number of 2 or more, preferably 3 or more and 33 or less, preferably 26 or less, such as trimethylsilyl group and triphenylsilyl group; trimethylsiloxy group, triphenylsiloxy group and the like Siloxy group having a carbon number of usually 2 or more, preferably 3 or more and usually 33 or less, preferably 26 or less; cyano group; a carbon number of 6 or more, usually 30 or less, such as a phenyl group and a naphthyl group The following aromatic hydrocarbon groups include aromatic heterocyclic groups having a carbon number of 3 or more, preferably 4 or more and 28 or less, preferably 17 or less, such as thienyl group and pyridyl group. In addition, it may be a substituent formed by combining two or three of these.
The molecular weight of the substituent is not particularly limited, but it is usually 400 or less, preferably 250 or less.
Although it does not specifically limit unless the effect of this invention is impaired remarkably, Preferably, it is preferable that it is at least one selected from the group which consists of an alkyl group, an aromatic hydrocarbon group, and a halogen atom.

<Specific Example of Structural Unit Represented by Formula (1)>
Although the specific example of a structural unit represented by Formula (1) is shown below, it is not specifically limited to this.

The charge transporting compound of the present invention preferably further contains a structural unit represented by the following formula (3). In order to promote transfer of charge by including the structural unit represented by the following formula (3), there is a tendency that driving at a low voltage can be performed. The structural unit represented by the formula (3) in the charge transport compound of the present invention may contain the structural unit represented by the formula (1) or may be different.

<Ar ²¹ and Ar ²² >
Specific examples of the substituted or unsubstituted aromatic ring group having 3 to 60 ring forming atoms of Ar ²¹ and Ar ²² are exemplified by the substituted or unsubstituted ring forming atom number 3 represented by Y ¹ in Formula (1). It is synonymous with the bivalent group derived from the aromatic ring of 60 or less, and the substituent which it may have is also synonymous. Among them, it is composed of a benzene ring, a naphthalene ring, a fluorene ring, a divalent group derived from a carbazole ring, and a bivalent group derived from biphenyl because the charge is delocalized efficiently and excellent in stability and heat resistance. Rings or groups selected from the group are more preferred. Particularly preferred is a benzene ring, a fluorene ring, a carbazole ring or a bivalent group derived from biphenyl.

<R ²¹ >
R ²¹ represents a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms, or a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms. Among these, a substituted or unsubstituted aromatic ring group having 3 to 60 ring forming atoms tends to be able to be driven at a low voltage, which is preferable.

(R ²¹ substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms)
Specific examples of the substituted or unsubstituted aromatic ring group having 3 to 60 ring forming atoms of R ²¹ are the substituted or unsubstituted ring forming atoms having 3 to 60 ring represented by Y ¹ in the formula (1) It is synonymous with the aromatic ring group of, and the substituent which it may have, the preferable range, the preferable form, the preferable reason, etc. are also synonymous.

(Substituted or unsubstituted alkylene group having 1 or more and 20 or less carbon atoms of R ²¹ )
The substituted or unsubstituted alkylene group having 1 to 20 carbon atoms represented by R ^{21 has} the same meaning as the substituted or unsubstituted alkylene group having 1 to 20 carbon atoms represented by Y ¹ in Formula (1), The substituent which may be substituted, the preferable range, the preferable form, the preferable reason, etc. are also synonymous.

<a>
a is an integer of 1 or more and 5 or less. Preferably it is one or more, Preferably it is three or less. Within these ranges, the effect of the stability of the compound tends to be obtained.
Ar ²¹ in the case where a is 2 or more may be the same or different.
When Ar ²¹ is 2, the combination of Ar ²¹ is not particularly limited, but, for example, a combination of substituted or unsubstituted aromatic ring groups having 3 to 60 ring atoms, specifically, a phenylene group and Combinations of divalent groups derived from a fluorene group and the like can be mentioned.

<B>
b is an integer of 0 or more and 5 or less. R ²¹ when b is 2 or more may be the same or different.

(Combination of Ar ²¹ , Ar ²² and R ²¹ )
The combination of Ar ²¹ , Ar ²² and R ²¹ is not particularly limited, but Ar ²¹ is an aromatic hydrocarbon group, Ar ²² is a fluorene and / or an aromatic hydrocarbon group, and R ²¹ is an aromatic hydrocarbon group And the like. These combinations tend to efficiently delocalize the charge and to be excellent in stability and heat resistance.

Any of the above Ar ²¹ , Ar ²² and R ²¹ may further have a substituent, as long as not departing from the spirit of the present invention. The molecular weight of the substituent is preferably 400 or less, and more preferably 250 or less. Although the kind in particular of substituent is not restrict | limited, The said substituent group W is mentioned as an example.

Although the specific example of a structural unit represented by Formula (3) is shown below, it is not specifically limited to this.

<Other Structure that Charge Transport Compound May Have>
When the charge transporting compound of the present invention is a polymer containing a structural unit represented by the formula (1), the main chain may further have a structural unit represented by the following formula (12) .

[In the formula (12), p1 represents an integer of 1 to 3, and
R ¹³ and R ¹⁴ each independently represent a hydrogen atom, an alkyl group which may have a substituent, an aromatic hydrocarbon group or an aromatic heterocyclic group.
When a plurality of R ¹³ and R ¹⁴ exist, they may be the same or different.
The crosslinking group represented by Formula (2) or another crosslinking group may be bonded to R ¹³ and / or R ¹⁴ . ]

When the charge transporting compound of the present invention is a polymer containing a structural unit represented by the formula (1), a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms is further added to the main chain. It is also preferable to have. The preferred structure of the substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms is the same as the substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms in Y 1 described above.

Molecular weight of charge transport compound etc.
The charge transporting compound of the present invention may be any one containing a structural unit represented by the formula (1), and may be a low molecule or a polymer, as long as the effects of the present invention are not significantly impaired. It is arbitrarily selected according to the application. When the charge transporting compound of the present invention is a low molecular weight compound, its molecular weight is usually 5,000 or less, preferably 4,000 or less, more preferably 3,000 or less, still more preferably 2,000 or less, and usually 400 The above range is preferably 500 or more, more preferably 600 or more, and still more preferably 700 or more. When the charge transporting compound of the present invention is a polymer, its weight average molecular weight is usually 1,000,000 or less, preferably 200,000 or less, more preferably 100,000 or less, and usually 5,000. The above range is preferably 8,000 or more, more preferably 10,000 or more. The charge transporting compound of the present invention is preferably a polymer.

When the charge transporting compound of the present invention has a low molecular weight, the glass transition temperature, the melting point, the decomposition temperature and the like do not become too low because the molecular weight is at least the lower limit, and the charge transporting compound and the organic thin film formed Heat resistance tends to be obtained. Therefore, there is a tendency to improve the device performance by suppressing the decrease in film quality due to recrystallization, migration of molecules, and the like, and the increase in impurity concentration accompanying the thermal decomposition of the material. Also in the case of a polymer, although it is not as remarkable as a low molecule, when the molecular weight is at least the above lower limit, heat resistance tends to be obtained. On the other hand, when the molecular weight of the charge transporting compound of the present invention is not more than the above upper limit, the solubility of the charge transporting compound of the present invention in the solvent tends to be improved in the solvent for both low and high molecular weight polymers. Purification may be easier. In addition, it tends to be easy to form a thin film at the time of film formation and to adjust the thickness of the formed organic thin film.

Here, the weight average molecular weight of the polymer charge transporting compound is a value in terms of polystyrene measured by gel permeation chromatography (GPC).

When the charge transporting compound of the present invention is a polymer compound, the charge transporting compound of the present invention comprises the structural unit represented by the formula (1) and the structural unit represented by the formula (3). In the case where the ratio of the structural unit represented by the formula (1) and the structural unit represented by the formula (3) is smaller than that of the structural unit 1 of the formula (1), the structural unit represented by the formula (3) is It is preferable from the viewpoint of the device performance that it is 0.5 to 1000, and particularly preferably 5 to 100. In addition, when the sum of all the structural units forming the charge transporting compound including the structural unit represented by the formula (1) is 1, that is, since it is excellent in charge transportability and stability in charge transport, that is, The number of structural units represented by the formula (1), the number of structural units represented by the formula (3), the number of structural units represented by the formula (12), the formula (1) and the formula When the total number of substituted or unsubstituted aromatic ring groups having 3 to 60 ring atoms, which is a main chain structure other than (3), is 1, the number of structural units represented by the formula (1) and the formula The total number of structural units represented by (3) is preferably 0.5 or more, more preferably 0.7 or more, more preferably 0.8 or more, preferably 0.9999 or less, and 0.999 or less preferable.

The reason why the charge transporting compound of the present invention preferably has the structure of Formula (1) is as follows. When a film using the composition of the present invention is used as a charge transport film, the nitrogen atom of the formula (1) is an atom which greatly contributes to charge transport. X ^{1 in} Formula (1) is a crosslinking group represented by Formula (2), and when the composition of the present invention is formed into a film, this crosslinking group forms a crosslinked structure, and the nitrogen atom of Formula (1) is It is fixed more. By immobilizing the nitrogen atom of the formula (1) in a crosslinked structure, it is considered that molecular motion is suppressed, charge transport is facilitated, and a stable, highly durable structure is obtained.
The charge transporting compound of the present invention having the structure of Formula (1) preferably has a crosslinking group different from the crosslinking group represented by Formula (2) in addition to the crosslinking group represented by Formula (2) . In this case, as in the case of the crosslinking group represented by formula (2), it is more preferable to bond to a nitrogen atom. In particular, when the charge transporting compound of the present invention is a polymer compound, a crosslinking group different from the crosslinking group represented by the formula (2) is preferably bonded to a nitrogen atom constituting the main chain. The reason is that, when the film using the composition of the present invention is used as a charge transport film, the nitrogen atom of the main chain which greatly contributes to the charge transportability, as well as the crosslinkable group represented by the formula (2), It is thought that this is because the structure is fixed through intercalation, molecular movement is suppressed, charge transport is easy, and a stable and durable structure is obtained. The crosslinking group which may be possessed in addition to the crosslinking group represented by the formula (2) is a crosslinking group which may be possessed by the compound A, and is represented by the formula (5), formula (6) or Formula (7) is mentioned, It is preferable that it is Formula (6) or Formula (7).
Furthermore, it is more preferable that the charge transporting compound of the present invention has only the formula (2) as a crosslinking group. When the number of the crosslinkable group of the charge transportable compound of the present invention is one, it is considered that the fluctuation of the position where the crosslinkable group is bonded due to the production lot of the charge transportable compound is small and stable production is easy. Therefore, it is considered that the cross-linking structure occurring in the composition is also less varied even if the production lot changes, and a stable film can be supplied. This is considered to be particularly remarkable when the charge transporting compound of the present invention is a polymer compound.

[Compound A (a compound having a structural unit represented by Formula (5), Formula (6) or Formula (7))]
The compound A is a compound having a structural unit represented by the following formula (5), formula (6) or formula (7).

<Formula (5)>
(E ¹ , E ² and E ³ )
E ¹ , E ² and E ³ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms, a fluorine Represents an atom or a substituted carbonyl group. Among these, a hydrogen atom or an unsubstituted alkyl group having 1 to 20 carbon atoms is preferable because the stability of the compound tends to be improved.

When E ¹ , E ² and E ³ have a substituent, examples of the substituent include one or more selected from the above-mentioned substituent group W.

(Substituted or unsubstituted alkyl group having 1 to 20 carbon atoms or more, substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms)
As a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms or more and a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms, E ¹ , E ² and E ³ may be represented by R of the formula (2) ¹¹ has the same meaning as the aromatic ring group or a substituted or unsubstituted C 1 or more 20 or more carbon atoms in the alkyl group and a substituted or unsubstituted ring atoms 3 to 60, has also been substituents, preferred ranges, Preferred embodiments, preferred reasons and the like are also synonymous.

(Substituted carbonyl group)
Examples of the substituted carbonyl group include alkyloxycarbonyl groups such as methyloxycarbonyl, ethyloxycarbonyl, butyloxycarbonyl, hexyloxycarbonyl, nonyloxycarbonyl and the like.
Among these, methyloxycarbonyl and ethyloxycarbonyl are preferable because they improve the stability of the film.
The combination of E ¹ , E ² and E ³ is independent of each other and is not particularly limited. However, it is preferable that E ² and E ³ are not simultaneously a hydrogen atom since the stability of the compound tends to be improved.

<Formula (6)>
In the formula (6), * represents a bonding site bond, and represents bonding to any atom contained in parentheses as in the following (6-a) to (6-d).

(R ³¹ )
R ³¹ is a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms And a substituted or unsubstituted alkyloxy group having 1 to 10 carbon atoms, a fluorine atom or a substituted carbonyl group. Further, they may be bonded to each other by adjacent substituents to form a ring.
Among these, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms and a substituted or unsubstituted alkyloxy group having 1 to 10 carbon atoms are preferable because the stability of the compound is high. Particularly preferred is a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms.

A substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms, a fluorine atom or a substituted carbonyl group is an E ^{1 of the} formula (5) And E ² and E ³ respectively have the same meaning, and may have a substituent, a preferable range, a preferable form, a preferable reason and the like.
The number of carbon atoms of the substituted or unsubstituted alkenyl group having 1 to 20 carbon atoms is not particularly limited, but is 1 or more and 20 or less, more preferably 10 or less. Within these ranges, the effect of the stability of the compound tends to be obtained.
Specific examples of the substituted or unsubstituted alkenyl group having 1 to 20 carbon atoms include a vinyl group, a propenyl group and a butenyl group.
The alkenyl group may have a substituent, and examples of the substituent include the substituent group W.

(J)
j is an integer of 0 or more and 5 or less. Preferably it is 3 or less. By being in these ranges, a high effect of the stability of the compound tends to be obtained.
R ³¹ when j is 2 or more may be the same or different.

<Formula (7)>
In the formula (7), * represents a binding site bond, and represents bonding to any atom contained in parentheses as in the following (7-a) to (7-d).

<R ⁴¹ >
R ⁴¹ is a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aromatic ring having 3 to 60 ring atoms And a substituted or unsubstituted alkyloxy group having 1 to 10 carbon atoms, a fluorine atom or a substituted carbonyl group. Further, they may be bonded to each other by adjacent substituents to form a ring.
Each group of R ⁴¹ has the same meaning as each group of R ^31. The substituents which may be possessed, the preferred range, the preferred embodiment, the preferred reason and the like are also the same.

<Y>
y is an integer of 0 or more and 5 or less. Preferably it is 3 or less. By being in these ranges, a high effect of the stability of the compound tends to be obtained.
R ⁴¹ in the case where y is 2 or more may be the same or different.

The content of the compound A in the composition of the present invention is not particularly limited. The content of the compound A is 50, relative to the total amount of the charge transporting compound containing the structure represented by the formula (1), the compound A and the charge transporting compound not containing the structure represented by the formula (1). It is preferable that it is mass% or less, and it is more preferable that it is 30 mass% or less. Moreover, it is preferable that it is 0.1 mass% or more, and it is more preferable that it is 1 mass% or more. Within these ranges, the effect of improving the stability of the coating film tends to be obtained. Within these ranges, the drive voltage is suppressed, and the film tends to be stabilized.
In the case where the composition of the present invention does not contain the charge transporting compound which does not contain the structure represented by the formula (1), the ratio of the content is the structure represented by the formula (1) The content of the compound A relative to the total amount of the charge transporting compound containing the compound A and the compound A is shown.

It is preferable that it is a structural unit represented by Formula (6) or (7) among the structural units represented by said Formula (5), Formula (6), or Formula (7).
The compound A of the present invention is preferably a polymerization initiator. When the compound A is a polymerization initiator, the crosslinking reaction of the composition of the present invention is promoted.

Furthermore, the compound A of the present invention is preferably an electron accepting compound. The electron accepting compound tends to be capable of driving at a low voltage. The electron accepting compound refers to a compound which withdraws an electron from a certain compound, oxidizes the compound, and is itself reduced.
Since the charge transporting compound containing the structure represented by the formula (1) of the present invention is an arylamine having a nitrogen atom in the main chain or main skeleton, this effect can be obtained by the compound A being an electron accepting compound. It can be expected to appear more prominently.
The electron accepting compound is not particularly limited as long as it has a structural unit represented by Formula (5), Formula (6) or Formula (7), and a known electron accepting compound can also be used.
The mother skeleton of the electron accepting compound is not particularly limited, but is preferably an ionic compound, more preferably an ionic compound having a counter anion, in terms of durability of the organic electroluminescent element and reduction in voltage, particularly preferably an ionic compound It is preferably an ionic compound consisting of a non-coordinating anion and a cation.

<Preferred Structure of Compound A>
Among the compounds A, a compound represented by the following formula (4) is preferable from the viewpoint of durability of the organic electroluminescent element and reduction in voltage.

[In the formula (4),
Y ^- represents an anion, Z ⁺ represents a cation, and a pair of Y ^- and Z ⁺ represents a compound,
L ¹ represents a single bond, a chalcogen atom, a carbonyl group, a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms, or an substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms;
L ¹ is bound to Y ^- or Z ⁺ ,
L ² is represented by the above formula (5), formula (6) or formula (7),
d and e are each independently an integer of 0 to 5, and when d is 2 or more, L ¹ may be the same or different, and when e is 2 or more, L ² may be the same or different And at least one e is 1 or more,
f is an integer of 1 or more and 4 or less, and when f is 2 or more, L ¹ , L ² , d and e in the formula (4) may be the same or different.
When f is 2 or more, e is an integer of 1 or more and 5 or less, and at least one e is 1 or more. ]

<Y ^->
Y ^- represents an anion.
The anion represents a halide ion, a substituted sulfonate, an anion consisting of a metal atom and a fluorine atom, an oxoanion, a substituted amide, and an organic boron anion. Preferred are substituted sulfonates, anions comprising a metal atom and a fluorine atom, substituted amides, organic boron anions, and particularly preferred are organic boron anions. These tend to drive at low voltage.

Specifically as a halide ion, a chloride ion, a bromide ion, an iodide ion is mentioned, A bromide ion is preferable.
Specific examples of the substituted sulfonate include trifluoromethanesulfonate and nonafluorobutanesulfonate, and trifluoromethanesulfonate is preferable.
Specific examples of the anion composed of a metal atom and a fluorine atom include hexafluorophosphate, tetrafluoroborate, and hexafluoroarsenate, and examples include hexafluorophosphate and tetrafluoroborate.
Specific examples of the oxo anion include perchlorate ion and molybdate ion, and molybdate ion is preferable.
Specific examples of the substituted amide include bis (perfluoromethanesulfonyl) imide, bis (perfluorobutanesulfonyl) imide, bis (perfluorohexanesulfonyl) imide and the like, and bis (perfluorobutanesulfonyl) imide is preferable.
Specific examples of the organic boron anion include tetraphenylborate, tetrakis (perfluorophenyl) borate, tris (2,3,5,6-tetrafluoro-4-trifluoromethylphenyl) (perfluorobiphenyl-4-yl) Borate, tetrakis (2,3,5,6-tetrafluoro-4-trifluoromethylphenyl) borate, tetrakis (perfluorobiphenyl-4-yl) borate and the like, and tris (2,3,5,6- Tetrafluoro-4-trifluoromethylphenyl) (perfluorobiphenyl-4-yl) borate and tetrakis (perfluorobiphenyl-4-yl) borate are preferred.

<Z ⁺ >
Z ⁺ represents a cation.
The cation represents an iodonium cation, a sulfonium cation, a carbocation, an oxonium cation, an ammonium cation, a phosphonium cation, a cycloheptyllyenyl cation or a ferrocenium cation having a transition metal atom, and is preferably an iodonium cation.

Specific examples of the iodonium cation include diphenyliodonium cation, bis (4-t-butylphenyl) iodonium cation, 4-t-butoxyphenylphenyliodonium cation, 4-methoxyphenylphenyliodonium cation, 4-isopropylphenyl-4-methyl Phenyliodonium cation etc. are mentioned.
Specific examples of sulfonium cations include triphenylsulfonium cation, 4-hydroxyphenyldiphenylsulfonium cation, 4-cyclohexylphenyldiphenylsulfonium cation, 4-methanesulfonylphenyldiphenylsulfonium cation, (4-t-butoxyphenyl) diphenylsulfonium cation, Bis (4-t-butoxyphenyl) phenylsulfonium cation, 4-cyclohexylsulfonylphenyldiphenylsulfonium cation and the like can be mentioned.

Specific examples of the carbocation include trisubstituted carbocations such as triphenyl carbocation, tri (methylphenyl) carbocation and tri (dimethylphenyl) carbocation.
Specific examples of the ammonium cation include trialkyl ammonium cations such as trimethyl ammonium cation, triethyl ammonium cation, tripropyl ammonium cation, tributyl ammonium cation, tri (n-butyl) ammonium cation and the like; N, N-diethylanilinium cation, N, N-dialkylanilinium cations such as N, N-2,4,6-pentamethylanilinium cation; and dialkylammonium cations such as di (isopropyl) ammonium cation and dicyclohexylammonium cation.

Specific examples of the phosphonium cation include tetraarylphosphonium cations such as tetraphenylphosphonium cation, tetrakis (methylphenyl) phosphonium cation, tetrakis (dimethylphenyl) phosphonium cation and the like; tetraalkylphosphoniums such as tetrabutylphosphonium cation and tetrapropylphosphonium cation And the like. Among these, iodonium cations, carbocations, and sulfonium cations are preferable, and iodonium cations are more preferable, from the viewpoint of the film stability of the compound.

<Combination of Y ^- and Z ⁺ >
Y ^- and Z ⁺ represent a compound in a pair. The combination of Y ^- and Z ⁺ is not particularly limited, but is preferably a combination of an iodonium cation and an organic boron anion, and a combination of a sulfonium cation and an organic boron anion for the reason of improving the film properties. In particular, a combination of iodonium cation and organic boron anion is preferred

<L ¹ >
L ¹ represents a single bond, a chalcogen atom, a carbonyl group, a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms, or an substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms. Among these, it is preferred that L ¹ be a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms or a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms. It is preferable in terms of improvement.
Examples of the substituted or unsubstituted alkylene group having 1 to 20 carbon atoms and the substituted or unsubstituted aromatic ring having 3 to 60 ring atoms include a substituted or unsubstituted carbon atom represented by Y ^{1 in} formula (2) The alkylene group of 1 to 20 or more, and the substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms, each having the same meaning, and a substituent which may be possessed, a preferred range, a preferred embodiment, a preferred reason, etc Is also synonymous.
L ¹ may be substituted in place of the Y 2 ^- or Z ⁺ hydrogen atom or fluorine atom.

<D>
d is an integer of 0 or more and 5 or less. Preferably it is one or more, Preferably it is two or less. By being in these ranges, the effect of voltage reduction tends to be obtained.
L ¹ when d is 2 or more may be the same or different. When d is 2 or more, the combination of L ¹ is not particularly limited, and examples thereof include a combination of an alkylene group which may be substituted and an aromatic ring group which may be substituted.

<L ² >
L ² is represented by the aforementioned formula (5), formula (6) or formula (7). Formula (5), Formula (6) or Formula (7) represents a crosslinking group. When L ² is a crosslinking group represented by Formula (5), Formula (6) or Formula (7), the stability of the film is obtained, and the yield also tends to be improved. Moreover, among these, it is preferable that it is a structural unit represented by Formula (6) or (7).
The preferred structure of the structural unit represented by Formula (5), Formula (6) or Formula (7) is as described above.

<E>
e is an integer of 0 or more and 5 or less, and at least one e is 1 or more. Preferably it is one or more, Preferably it is three or less. The voltage reduction effect tends to be obtained by being in these ranges.
L ² when e is 2 or more may be the same or different. When L ² is 2 or more, the combination of the plurality of L ² is not particularly limited, and examples thereof include combinations of Formula (5) and Formula (7). Since the structure after the crosslinking reaction is uniform, it is preferable that L ^{2 be} the same when e is 2 or more.
When f described later is 2 or more, at least one e may be an integer of 1 or more and 5 or less, and e may be 0.

<F>
f is an integer of 1 or more and 4 or less. When f is 2 or more, L ¹ , L ² , d and e in the formula (4) may be the same or different.

<Combination of L ¹ , L ² , E ¹ , E ² , E ³ and R ³¹ >
The combination of L ¹ , L ² , E ¹ , E ² , E ³ and R ³¹ is not particularly limited. For example, L ¹ is a benzene ring group, L ² is a formula (5), E ¹ and E ³ are hydrogen It is preferably an atom, a combination in which E ² is an alkyl group, or L ¹ is a benzene ring group, L ² is a group represented by the formula (6) or the like for the reason of reduction in voltage. As described later, L ² is preferably represented by Formula (6) or Formula (7).

Each of L ¹ , L ² , E ¹ , E ² , E ³ and R ³¹ may further have a substituent unless it is against the spirit of the present invention. The molecular weight of the substituent is preferably 400 or less, and more preferably 250 or less. The type of substituent is not particularly limited, but is preferably one or more selected from the above substituent group W.

Molecular Weight of Compound A
The molecular weight of the compound A of the present invention is usually in the range of 900 or more, preferably 1000 or more, more preferably 1200 or more, and usually 10000 or less, preferably 5000 or less, more preferably 3000 or less. When the molecular weight of the compound A is not less than the above lower limit, it is stable at heating for crosslinking and is preferable, and when it is not more than the above upper limit, it is suitably diffused at the heating for crosslinking and the crosslinking reaction is promoted.

Although the specific example of a compound represented by Formula (4) is shown below, it is not specifically limited to this.

In addition, in the electron accepting ionic compound represented by the formula (101) described later, an electron accepting compound AC represented by the formula (Z-1) or the formula (Z-2) as a crosslinking group is used as the compound A Is also preferred.

[Method of preparing composition]
The composition of the present invention contains at least the charge transporting compound of the present invention and the compound A, and is prepared by mixing with other components. The composition of the present invention may contain any one kind of the charge transporting compound of the present invention alone, or may contain two or more kinds in any combination and ratio. The composition of the present invention may contain any one kind of the compound A of the present invention alone, or may contain two or more kinds in any combination and ratio. The same applies to the following polymerization initiator, solvent and the like.

[solvent]
The composition of the present invention may contain a solvent, various additives and the like. In particular, when the charge transport film is formed by a wet film formation method using the composition of the present invention, it is preferable to use a solvent to dissolve the charge transport compound and the compound A described above.

Here, a charge transporting ionic compound is formed by mixing the compound A of the present invention with the charge transporting compound of the present invention. That is, the charge transporting ionic compound is a compound derived from the compound A of the present invention and the charge transporting compound of the present invention. For this reason, the composition containing the charge transporting ionic compound of the present invention may contain other components as necessary, and in the case of forming a charge transporting film by a wet film forming method, using a solvent It is preferable to dissolve the charge transporting ionic compound of the present invention.

The type of the solvent contained in the composition of the present invention is not particularly limited as long as it can dissolve both the compound A and the charge transport compound described above. Here, the solvent for dissolving the compound A and the charge transporting compound preferably dissolves the charge transporting compound at 0.005% by mass or more, more preferably 0.5% by mass or more, still more preferably 1% by mass or more It is a solvent. In addition, the solvent dissolves the compound A preferably in an amount of 0.001% by mass or more, more preferably 0.1% by mass or more, still more preferably 0.2% by mass or more.
The charge transporting compound of the present invention has high solubility and is excellent in storage stability after dissolution, so various solvents can be applied.

As preferable solvents, for example, ether solvents and ester solvents can be mentioned. Specifically, as ether solvents, for example, aliphatic ethers such as ethylene glycol dimethyl ether, ethylene glycol diethyl ether, propylene glycol-1-monomethyl ether acetate (PGMEA); 1,2-dimethoxybenzene, 1,3 And aromatic ethers such as dimethoxybenzene, anisole, phenetole, 2-methoxytoluene, 3-methoxytoluene, 4-methoxytoluene, 2,3-dimethylanisole, 2,4-dimethylanisole and the like. As ester solvents, for example, aliphatic esters such as ethyl acetate, n-butyl acetate, ethyl lactate and n-butyl lactate; phenyl acetate, phenyl propionate, methyl benzoate, ethyl benzoate, propyl benzoate, benzoic acid and aromatic esters such as n-butyl. Any of these may be used alone, or two or more may be used in any combination and ratio.

Examples of solvents that can be used other than the above-mentioned ether solvents and ester solvents include, for example, aromatic hydrocarbon solvents such as benzene, toluene and xylene, and amides such as N, N-dimethylformamide, N, N-dimethylacetamide and the like A system solvent, dimethylsulfoxide etc. are mentioned. Any of these may be used alone, or two or more may be used in any combination and ratio. In addition, one or more of these solvents may be used in combination with one or more of the above-mentioned ether solvents and ester solvents. In particular, aromatic hydrocarbon solvents such as benzene, toluene and xylene may be used in combination with ether solvents and ester solvents because their ability to dissolve electron accepting compounds and free carriers (cation radicals) is low. preferable.

When a solvent is used, the concentration of the solvent to the composition of the present invention is preferably 10% by mass or more, more preferably 30% by mass or more, and further preferably 50% by mass or more. The concentration of the solvent with respect to the composition is preferably in the range of 99.999% by mass or less, more preferably 99.99% by mass or less, and still more preferably 99.9% by mass or less. In addition, when mixing and using 2 or more types of solvent, it is made for the sum total of these solvent to satisfy | fill this range.

In addition, when using the composition of this invention for an organic electroluminescent element, in order that an organic electroluminescent element may be formed by laminating | stacking the layer which consists of many organic compounds, it is required that all layers be uniform layers. . In the case of forming a layer by a wet film formation method, if water is present in the solution (composition) for forming a thin film, the water is mixed in the coating film and the uniformity of the film is impaired. The smaller one is preferable. Further, in general, a material that is significantly deteriorated by moisture such as a cathode is often used in the organic electroluminescent device, and therefore the presence of moisture is not preferable also from the viewpoint of the deterioration of the device.

Specifically, the amount of water contained in the composition of the present invention is preferably suppressed to 1% by mass or less, preferably 0.1% by mass or less, and more preferably 0.05% by mass or less.
Examples of the method for reducing the amount of water in the composition include a nitrogen gas seal, use of a desiccant, dehydration of the solvent in advance, and use of a solvent with low water solubility. Among them, it is preferable to use a solvent having a low solubility of water from the viewpoint of preventing the phenomenon in which the solution coating film absorbs moisture in the air and whitening during the coating step.

When used for film formation by a wet film formation method, the composition of the present invention is a solvent having a low water solubility, specifically, for example, a water solubility at 25 ° C. of 1% by mass or less, preferably 0.1 It is preferable to contain the solvent which is not more than 10% by mass, preferably not less than 10% by mass, more preferably not less than 30% by mass, especially not less than 50% by mass, based on the whole composition.

[Charge Transportable Compound Containing No Structure Represented by Formula (1)]
As the charge transporting compound which does not contain the structure represented by the formula (1), known charge transporting compounds can be used. For example, PDOT / PSS, polyphenylene vinylene, polypyrrole, polyvinylcarbazole and the like can be mentioned. Further, a charge transporting compound which contains the structure represented by the formula (3) but does not contain the structure represented by the formula (1) is also preferable. More preferably, the charge transportable compound not containing the structure represented by the formula (1) includes the structure represented by the formula (3) from the viewpoint of stability of the composition and charge transportability, and the formula (1) It is a charge transportable compound which does not contain the structure represented by these.

[Polymerization initiator]
The composition of the present invention preferably contains a polymerization initiator. Specifically as a polymerization initiator contained in the composition of this invention, a radical polymerization initiator, a cationic polymerization initiator, an anionic polymerization initiator etc. are mentioned. Among these, a cationic polymerization initiator is preferable.

Examples of radical polymerization initiators include 4,4'-dimethoxybenzyl, benzophenone, 2-isonitrosopropiophenone, benzoin isopropyl ether, azobis (isobutyronitrile), benzoyl peroxide, di-tert-butyl peroxide and the like. Be

As a cationic polymerization initiator, bis (4-tert-butylphenol) iodonium hexafluorophosphate, 4-isopropyl-4'-methyldiphenyliodonium tetrakis (pentafluorophenyl) borate, 4-isopropyl-4'-methyldiphenyliodonium tetrakis (Perfluorophenyl) borate, 4-isopropyl-4′-methyldiphenyliodonium tris (2,3,5,6-tetrafluoro-4-trifluoromethylphenyl) (perfluorobiphenyl-4-yl) borate, 4- Isopropyl-4'-methyldiphenyliodonium tetrakis (2,3,5,6-tetrafluoro-4-trifluoromethylphenyl) borate, 4-isopropyl-4'-methyldiphenyliodonium tetrakis Examples include perfluoro (biphenyl-4-yl) borate, 4-nitrobenzenediazonium tetrafluoroborate, triphenylsulfonium tetrafluoroborate, dicyandiamide, cyclohexyl p-toluenesulfonate, diphenyl (methyl) sulfonium tetrafluoroborate and the like. .

Examples of the anionic polymerization initiator include acetophenone-O-benzoyl oxime, nifedipine, and 2-nitrobenzyl cyclohexylcarbamate.

Moreover, the polymerization initiator etc. as described in CMC publication "high molecular additive handbook" pages 121-129 (Taru Haruna, published in November 2010) are also mentioned.

The 5% mass loss start temperature of the polymerization initiator is not particularly limited, but is preferably 300 ° C. or less, more preferably 250 ° C. or less. The lower limit is not particularly limited, but is preferably 50 ° C. or more, more preferably 80 ° C. or more. By being in these ranges, the effect of improving storage stability tends to be obtained.

The polymerization initiation temperature of the polymerization initiator is not particularly limited, but is preferably 80 ° C. or more, more preferably 100 ° C. or more, and still more preferably 130 ° C. or more. The polymerization initiation temperature of the polymerization initiator is not particularly limited, but is preferably 300 ° C. or less, more preferably 250 ° C. or less. By being in these ranges, the effect of improving storage stability tends to be obtained.

As mentioned above, the compound A of the present invention is preferably a polymerization initiator. Accordingly, the compound A of the present invention preferably satisfies the 5% mass loss start temperature and the polymerization start temperature.

The content of the polymerization initiator in the composition of the present invention is not particularly limited. The content of the polymerization initiator is the total amount of the charge transporting compound containing the structure represented by the formula (1), the polymerization initiator and the charge transporting compound not containing the structure represented by the formula (1) And 50% by mass or less, and more preferably 30% by mass or less. Moreover, it is preferable that it is 0.1 mass% or more, and it is more preferable that it is 1 mass% or more. Within these ranges, the effect of improving the stability of the coating film tends to be obtained. Within these ranges, the drive voltage is suppressed, and the film tends to be stabilized.
In the case where the composition of the present invention does not contain the charge transporting compound which does not contain the structure represented by the formula (1), the ratio of the content is the structure represented by the formula (1) And the content of the polymerization initiator relative to the total amount of the charge transporting compound containing the compound and the polymerization initiator.

[Film formation using the composition of the present invention]
When a film is formed using the composition of the present invention, the composition of the present invention is preferably a solution containing a solvent, and the composition of the present invention is preferably subjected to wet film formation.

The wet film formation method refers to a method in which a composition containing a solvent is applied onto a substrate and the solvent is removed by drying to form a film. The coating method is not particularly limited, and examples thereof include spin coating, dip coating, die coating, bar coating, blade coating, roll coating, spray coating, capillary coating, ink jet method, screen printing, The gravure printing method, the flexographic printing method, etc. are mentioned.

As a method of drying and removing the solvent, usually, heating and drying are performed. Examples of heating means used in the heating step include clean ovens, hot plates, and infrared heating. As the infrared heating, a halogen heater, a ceramic-coated halogen heater, a ceramic heater or the like can be used.
Infrared heating directly applies heat energy to the substrate or film, so drying can be performed in a short time as compared to heating using an oven or a hot plate. Therefore, the influence of the heating atmosphere gas (moisture and oxygen) and the influence of micro dust can be minimized, and the productivity is improved, which is preferable.

The heating temperature is usually 80 ° C. or more, preferably 100 ° C. or more, more preferably 150 ° C. or more. The heating temperature is usually 300 ° C. or less, preferably 280 ° C. or less, more preferably 260 ° C. or less.
The heating time is usually 10 seconds or more, preferably 60 seconds or more, more preferably 90 seconds or more, and usually 120 minutes or less, preferably 60 minutes or less, more preferably 30 minutes or less.

It is also preferable to carry out vacuum drying before heating and drying.

The film thickness of the organic layer which formed the film of the composition of this invention into a film by the wet-film-forming method is 5 nm or more normally, Preferably 10 nm or more, More preferably, it is 20 nm or more. The film thickness is usually 1000 nm or less, preferably 500 nm or less, more preferably 300 nm or less.

As described above, the composition of the present invention suppresses the polymerization reaction even in the presence of the polymerization initiator, and maintains the crosslinking reactivity at high temperature. The reason is considered as follows.
The crosslinking reaction of the crosslinking group represented by the formula (2) is suppressed at normal temperature even in the presence of the compound A having the crosslinking group represented by the formulas (5) to (7). Like the crosslinking group represented by the formula (2), the crosslinking group represented by the formula (5) has a C 部位 C type double bond (vinyl group structure) and an E corresponding to the terminal thereof ^{Since 2} and E ³ are not hydrogen atoms at the same time, they have at least one substituent other than a hydrogen atom, so that at a normal temperature, the crosslinking reaction is suppressed and stable even in the presence of a polymerization initiator. And when heating, the crosslinking groups represented by Formula (5), and the crosslinking group represented by Formula (5) and the crosslinking group represented by Formula (2) will carry out a crosslinking reaction.

The crosslinking mechanism of the crosslinking group represented by the formulas (6) and (7) will be described with reference to the following formulas (6α) and (7α) which are structures excluding the bonding hand and the substituent. By heating, in the formulas (6α) and (7α), crosslinking reactions occur via diene structures such as the formulas (6β) and (7β), respectively. At this time, since the reactivity of the formula (6β) and the formula (7β) is high, the crosslinking reaction also occurs with the formula (2) which is a crosslinking group of the arylamine represented by the formula (1). Furthermore, since the formula (6β) and the formula (7β) have high reactivity in the diene structure, the crosslinking group of the formula (2) and the crosslinking group of the formula (6) are more reactive than the reaction between the crosslinking groups of the formula (2). Alternatively, the reaction with the crosslinking group of the formula (7) is dominant.

For the above reasons, the composition of the present invention comprises an arylamine represented by the formula (1) having a crosslinking group represented by the formula (2) and a crosslinking group represented by the formula (6) or the formula (7) It is preferable to contain the compound A and the compound A, since the crosslinking reaction of the composition is further promoted.

[Charge Transportable Compound Containing Structural Unit Represented by Formula (10)]
The present invention provides a novel charge transporting compound containing a structural unit represented by the following formula (10).

Wherein (10), X ¹ 'is a group represented by the following formula (11). ]

The charge transporting compound containing the structural unit represented by the formula (10) has high yield efficiency, and the composition containing the charge transporting compound is excellent in storage stability. Moreover, the organic electroluminescent element obtained using the charge transportable compound containing the structural unit represented by Formula (10) can be driven at a low voltage.
The reason why these effects can be obtained is not clear, but the following can be considered.

In the structural unit represented by the formula (10), an arylamine having a high mobility of positive charge is a main chain or a main skeleton, and has a crosslinking group represented by the formula (11). A C = C type double bond (vinyl group structure), which is a crosslinking site, is disposed from an atom via a substituent (linking group). When Y ¹ to which the double bond is directly bonded is a benzene ring (phenylene group), it is a styrene configuration having R ¹¹ ′ and R ¹² ′ as substituents. When the structural unit represented by the formula (10) is a polymer compound, since the crosslinking group is linked from the main chain of arylamine via the linking group, the main chain distortion of arylamine during crosslinking is suppressed. At the same time, it became possible to suppress side reactions as much as possible. Therefore, the yield efficiency is high, and the composition containing the charge transporting compound is excellent in storage stability.
The side reaction is expected to occur at the charge transport site of the polymer compound upon crosslinking of the polymer compound having a benzocyclobutene crosslinking group, and the charge transport compound having a crosslinking group of the present invention is not limited to this. Side reactions are suppressed. Accordingly, the charge transporting compound of the present invention is preferably a polymer compound, and more preferably having only the formula (11) as a crosslinking group.
On the other hand, in the charge transporting compound of the present invention, the following effects are considered to be obtained by the steric hindrance of the substituent substituted at both ends of the vinyl group.
1) Reduction of side reaction during polymer synthesis using Pd coupling 2) Suppression of polymerization reaction in the presence of a polymerization initiator And, on the other hand, since the polymerization reactivity at high temperature is maintained, the wet formation The film method enables easy lamination.

<Formula (10)>
The structural unit represented by Formula (10) is a structural unit which forms an arylamine structure. Among the arylamine structures, tertiary arylamine structures are preferred because of their high charge transportability and high stability during charge transport. Therefore, it is preferable that both ends of the nitrogen atom of Formula (10) are a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms.
The preferred structure of the substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms is the same as the substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms in Y ¹ described above.

Y ¹ ′ in the above formula (11) is a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms, a chalcogen atom, a carbonyl group, or a substituted or unsubstituted group as represented by Y ¹ in the above formula (2) It is the same as an unsubstituted C1 or more and 20 or less alkylene group, and a preferable range etc. are also the same.
R ¹¹ ′, R ¹² ′, k ′, m ′ and n ′ are respectively the same as R ¹¹ , R ¹² , k, m and n in the above-mentioned formula (2), and preferred ranges and the like are also the same. ^The same applies to the ring in which the substituent of ¹¹ 'and R ¹² ' combine to form a ring.

As a specific example of a structural unit represented by Formula (10), what satisfy | fills the said Formula (10) and (11) among what was illustrated as a specific example of a structural unit represented by above-mentioned Formula (1) It can be mentioned.
The charge transporting compound containing the structural unit represented by the formula (10) may further have the charge transporting compound containing the structural unit represented by the above formula (1). It is preferable from the viewpoint of charge transportability and stability during charge transport that it is a polymer compound. The preferable structure etc. of the structural unit represented by Formula (3) are the same as the structural unit represented by above-mentioned Formula (3).
Further, the charge transporting compound containing the structural unit represented by the formula (10) preferably further has a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms in the main chain.
The preferred structure of the substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms is the same as the substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms in Y ¹ described above.
When the charge transporting compound containing the structural unit represented by the formula (10) is a polymer compound, it may further have a crosslinking group other than the group represented by the formula (11). The crosslinking group which may further be contained is a crosslinking group represented by the formula (6) or (7), which is a crosslinking group which the compound A may have.

In addition, the preferred molecular weight of the charge transporting compound containing the structural unit represented by the formula (10), the ratio of the structural unit represented by the formula (1) to the structural unit represented by the formula (3), and the formula (10) The preferred structure and the like of the charge transporting compound containing the structural unit represented by and are the same as the charge transporting compound containing the structural unit represented by the above-mentioned formula (1).

<Composition Containing Charge-Transporting Compound Containing Structural Unit Represented by Formula (10)>
The charge transporting compound containing the structural unit represented by the formula (10) of the present invention can also be used as a composition containing other compounds and the like. Hereinafter, a composition containing a charge transporting compound containing a structural unit represented by the formula (10) is referred to as a composition X.

Although the compound etc. contained in the composition X are not particularly limited, in addition to the charge transporting compound containing the structure represented by the formula (10), the solvent, the polymerization initiator, and the structure represented by the formula (10) are included. It may contain a charge transportable compound, various additives and the like. The type and content of these components may be appropriately selected according to the application and purpose.

[Organic electroluminescent device]
Next, as to the organic electroluminescent device of the present invention, FIG. 1a to FIG. This will be described with reference to 1c. Note that Fig. 1a to FIG. 1c is a cross-sectional view schematically showing an example of the configuration of the organic electroluminescent device according to one embodiment of the present invention.

Fig. The organic electroluminescent element 100 a shown in 1 a includes a substrate 101, an anode 102 sequentially stacked on the substrate 101, a hole injection layer 103, a light emitting layer 105, and a cathode 107.

(substrate)
The substrate 101 is a support of the organic electroluminescent device 100a. Examples of the material for forming the substrate 101 include a quartz plate, a glass plate, a metal plate, a metal foil, a plastic film, a plastic sheet, and the like. Among these, transparent plastic sheets such as glass plates, polyesters, polymethacrylates, polycarbonates and polysulfones are preferable. In the case of using a plastic for the substrate 101, it is preferable to provide a dense silicon oxide film or the like on one side or both sides of the substrate 101 to enhance the gas barrier properties.

(anode)
The anode 102 is provided on the substrate 101 and plays a role of hole injection to the hole injection layer 103. Materials of the anode 102 include metals such as aluminum, gold, silver, nickel, palladium and platinum; conductive metal oxides such as oxides of indium and / or tin; halogenated metals such as copper iodide; carbon black And conductive polymers such as poly (3-methylthiophene), polypyrrole and polyaniline. As a method of forming the anode 102, usually, sputtering on a substrate 101, vacuum evaporation, etc .; metal fine particles such as silver, fine particles such as copper iodide, carbon black, conductive metal oxide fine particles or conductive polymer fines Method of dispersing powder etc. in suitable binder resin solution and coating on substrate 101; method of forming conductive polymer thin film directly on substrate 101 by electrolytic polymerization; coating conductive polymer solution on substrate 101 Methods etc. The anode 102 preferably has a visible light transmittance of usually 60% or more, particularly 80% or more. The thickness of the anode 102 is usually 1000 nm or less, preferably 500 nm or less, and usually 5 nm or more, preferably 10 nm or more.

(Hole injection layer)
The hole injection layer 103 is provided on the anode 102 and is provided between the anode 102 and the light emitting layer 105. The hole injection layer 103 may be provided directly on the anode 102, or another layer for transporting holes may be provided between the anode 102 and the hole injection layer 103. Preferably, the hole injection layer 103 is provided in direct contact with the anode 102, but a hole transport layer 104 described later, which is another layer, is provided between the hole injection layer 103 and the light emitting layer 105.

The hole injection layer 103 is preferably a layer containing an electron accepting compound and a hole transporting compound. For the electron accepting compound and the hole transporting compound, any of the commonly used compounds can be applied. For example, the charge transporting compound including the structural unit represented by the above-mentioned formula (1) can be hole transporting It can be used as a sex compound. Moreover, the compound of the structure represented by the above-mentioned Formula (4) can also be used as an electron-accepting compound.
The hole injection layer 103 is preferably formed using the composition of the present invention. The charge transporting compound containing the structural unit represented by the formula (1) and the preferable structure of the compound A, which are included in the composition of the present invention, are as described above.

A compound suitable as an electron accepting compound used for the hole injection layer 103 will be described later.

The method for forming the hole injection layer 103 is not particularly limited, and examples thereof include a vacuum evaporation method and a wet film formation method.
In the case of layer formation by a wet film formation method, the composition of the present invention is prepared, applied on the anode 102 by a wet film formation method such as spin coating method or dip coating method, and dried. To form

The film thickness of the hole injection layer 103 thus formed is usually in the range of 5 nm or more, preferably 10 nm or more, and usually 1000 nm or less, preferably 500 nm or less.

(Emitting layer)
On the hole injection layer 103, as shown in FIG. The light emitting layer 105 may be formed directly as shown in FIG.

The light emitting layer 105 is provided on the hole injection layer 103, and efficiently recombines electrons injected from the cathode 107 and holes transported from the hole injection layer 103 between electrodes given an electric field, and And materials that emit light efficiently by recombination. As a material for forming the light emitting layer 105, a conventionally known material may be appropriately used, but a metal complex such as an aluminum complex of 8-hydroxyquinoline, a metal complex of 10-hydroxybenzo [h] quinoline, a bisstyrylbenzene derivative, Low-molecular light-emitting materials such as bis-styrylarylene derivatives, metal complexes of (2-hydroxyphenyl) benzothiazole, silole derivatives, etc .; poly (p-phenylenevinylene), poly [2-methoxy-5- (2-ethylhexyloxy) -1 And a system in which a light emitting material and an electron transfer material are mixed with a polymer compound such as 2,4-phenylenevinylene], poly (3-alkylthiophene), polyvinylcarbazole and the like.

Also, for example, a metal complex such as aluminum complex of 8-hydroxyquinoline is used as a host material, a naphthacene derivative such as rubrene, a quinacridone derivative, a fused polycyclic aromatic ring such as perylene, etc. The light emission characteristics of the organic electroluminescent device, in particular, the driving stability can be greatly improved by doping so as to be an amount ranging from 10% by mass to 10% by mass.

A material suitable for forming the light emitting layer 105 will be described later.

The light emitting layer forming material is applied on the hole injection layer 103 by vacuum evaporation or wet film formation to form a thin film. The film thickness of the light emitting layer 105 thus formed is usually 10 nm or more, preferably 30 nm or more, and usually 200 nm or less, preferably 100 nm or less.

(cathode)
The cathode 107 plays a role of injecting electrons into the light emitting layer 105. The material used as the cathode 107 is preferably a metal having a low work function, and for example, a suitable metal such as tin, magnesium, indium, calcium, aluminum, silver or an alloy thereof is used. Specific examples include low work function alloy electrodes such as magnesium-silver alloy, magnesium-indium alloy, aluminum-lithium alloy and the like. The film thickness of the cathode 107 is usually in the same range as that of the anode 102. In order to protect the cathode 107 made of a low work function metal, it is effective to further deposit a metal layer having a high work function and stable to the atmosphere on this to increase the stability of the device. For this purpose, metals such as aluminum, silver, copper, nickel, chromium, gold and platinum are used. Furthermore, an extremely thin insulating film (film thickness 0.1 to 5 nm) such as LiF, MgF ₂ , Li ₂ O, etc. is inserted at the interface between the cathode 107 and the light emitting layer 105 to form a cathode. Efficiency can be improved.

(Hole transport layer)
Fig. In the organic electroluminescent device 100b shown in FIG. 1b, a hole transporting layer 104 and an electron transporting layer 106 are provided between the hole injecting layer 103 and the light emitting layer 105 in order to improve the light emission characteristics of the organic electroluminescent device. The other layers are shown in FIG. It has the same configuration as the organic electroluminescent device 100a shown in 1a.

The material of the hole transport layer 104 needs to be a material having high hole injection efficiency from the hole injection layer 103 and capable of efficiently transporting the injected holes. For this purpose, it is required to have an appropriate ionization potential, a large hole mobility, and a high stability, and to make it difficult for impurities serving as traps to be generated during production or use. Further, since the layer is in direct contact with the light-emitting layer 105, it is preferable that a substance which quenches light emission is not contained.

Examples of the material used to form the hole transport layer 104 include the charge transportable compound including the structural unit represented by Formula (1), the composition of the present invention including the compound A of the present invention, and the like. The hole transport layer 104 is formed by laminating them on the hole injection layer 103 by a wet film formation method. The film thickness of the hole transport layer 104 thus formed is usually in the range of 10 nm or more, preferably 30 nm or more, and usually 300 nm or less, preferably 100 nm or less.

(Electron transport layer)
The compound used for the electron transport layer 106 is required to be easy to inject electrons from the cathode 107 and to have a further large electron transport capability. As such an electron transporting material, for example, aluminum complex of 8-hydroxyquinoline, oxadiazole derivative or system in which they are dispersed in resin such as polymethyl methacrylate (PMMA), phenanthroline derivative, 2-t-butyl And -9,10-N, N'-dicyanoanthraquinonediimine, n-type hydrogenated amorphous silicon carbide, n-type zinc sulfide, n-type zinc selenide and the like. The film thickness of the electron transport layer 106 is usually 5 nm or more, preferably 10 nm or more, and usually 200 nm or less, preferably 100 nm or less.

(Hole blocking layer)
Fig. In the organic electroluminescent device 100c shown in 1c, a hole blocking layer 108 is provided between the light emitting layer 105 and the electron transport layer 106, and the other layers are shown in FIG. It has the same configuration as that of the organic electroluminescent device 100b shown in 1b.

The hole blocking layer 108 is provided between the light emitting layer 105 and the electron transport layer 106. The hole blocking layer 108 has a role of blocking holes transferred from the anode 102 from reaching the cathode 107 and a role of efficiently transporting electrons injected from the cathode 107 to the light emitting layer 105. The physical properties required of the material constituting the hole blocking layer 108 include high electron mobility and low hole mobility, large energy gap (difference between HOMO and LUMO), excited triplet level (T1) Is high. As a material of the hole blocking layer 108 which satisfies such conditions, for example, bis (2-methyl-8-quinolinolato) (phenolate) aluminum, bis (2-methyl-8-quinolinolato) (triphenylsilanolato) aluminum Mixed ligand complexes, etc., metal complexes such as bis (2-methyl-8-quinolato) aluminum-μ-oxo-bis- (2-methyl-8-quinolinolato) aluminum binuclear metal complex, distyrylbiphenyl derivatives, etc. Compounds, triazole derivatives such as 3- (4-biphenylyl) -4-phenyl-5 (4-tert-butylphenyl) -1,2,4-triazole, phenanthroline derivatives such as vasocuproin, and the like. Furthermore, a compound having at least one pyridine ring substituted at the 2, 4, and 6 positions is also preferable as the material of the hole blocking layer 108. The film thickness of the hole blocking layer 108 is optional as long as the effects of the present invention are not significantly impaired, but is usually 0.3 nm or more, preferably 0.5 nm or more, and usually 100 nm or less, preferably 50 nm or less is there.

Note that Fig. 1a to FIG. The organic electroluminescent devices 100a to 100c shown in 1c are not limited to the illustrated ones. For example, FIG. 1a to FIG. A structure reverse to that shown in 1c, that is, the cathode 107, the light emitting layer 105, the hole injection layer 103, and the anode 102 can be sequentially stacked on the substrate 101. Also, as long as the purpose of the present invention is not violated, FIG. 1a to FIG. It is also possible to provide an additional optional layer between the layers shown in 1c or to optionally provide two or more optional layers. Furthermore, it is also possible to provide an organic electroluminescent element between two substrates of which at least one is highly transparent.

The layer containing the charge transporting compound containing the structural unit represented by the formula (1) of the present invention is not only the hole injection layer 103 in contact with the anode 102, the hole transport layer 106, but also the anode 102 and the cathode. It may be any layer provided between it and 107. In particular, the hole injection layer 103 and / or the hole transport layer 104 is preferably between the anode 102 and the light emitting layer 105, and more preferably at least the hole transport layer 103.

[Suitable Hole Injection Layer Forming Material]
The compound suitable as a formation material of the positive hole injection layer containing an electron-accepting compound and a positive hole transport compound is demonstrated below.

The electron accepting compound refers to a compound which withdraws an electron from a certain compound, oxidizes the compound, and is itself reduced. The electron accepting compound is preferably an ionic compound. Hereinafter, the electron accepting compound which is an ionic compound is referred to as an "electron accepting ionic compound". Electron accepting ion compounds include the compounds described in WO 2005/089024 and WO 2017-164268.

<Electron Acceptable Compound AC>
Specifically, as the electron accepting ion compound, a compound comprising a counter anion which is a non-coordinating anion represented by the following formula (101) and a counter cation is preferable. Hereinafter, the electron accepting compound represented by the following formula (101) is referred to as “electron accepting compound AC”.

[In the formula (101), B ^- represents a boron ion,
Ar ¹⁰⁰ each independently represents an aromatic ring group which may have a substituent or a fluorine-substituted alkyl group,
F ₄ represents that 4 fluorine atoms are substituted,
F _(5-g) represents that 5-g fluorine atoms are substituted,
p independently represents an integer of 0 to 5, and
g each independently represents an integer of 0 to 5;
p + q 1 1 and
A ⁺ represents a counter cation. ]

The electron accepting compound AC is preferably an electron accepting compound having a crosslinking group, and more preferably at least one of Ar ¹⁰⁰ has a crosslinking group. The crosslinking group in this case is not particularly limited, but is preferably a group selected from the following crosslinking group group Z, and more preferably a group represented by the following formula (107) or formula (108).

The electron accepting compound AC having a crosslinking group is preferably an ionic compound having a crosslinking group in the counter anion. The crosslinking group in this case is not particularly limited, but is preferably a group represented by Formula (107) or Formula (108) described later.

(Counter anion)
The counter anion structure of the electron accepting compound AC represented by the above formula (101) is described in the following formula (106).

[The definition of Ar ¹⁰⁰ , F ₄ , F _(5-g) , p and g in the formula (106) is the same as that of the formula (101). ]

The aromatic ring group in Ar ¹⁰⁰ represents an aromatic hydrocarbon ring group, an aromatic heterocyclic group, or a substituent formed by connecting the aromatic hydrocarbon ring group and the aromatic heterocyclic group. As an aromatic ring group, one having 30 or less carbon atoms is preferable because the voltage and the life become good.

The aromatic ring group is preferably a single ring, a 2-6 condensed ring or a group in which two or more of these aromatic rings are linked. Preferred specific examples of the aromatic ring group are
Benzene ring, naphthalene ring, anthracene ring, phenanthrene ring, perylene ring, tetracene ring, pyrene ring, benzpyrene ring, chrysene ring, triphenylene ring, acenaphthene ring, fluoranthene ring, fluorene ring, biphenyl ring, terphenyl ring, quaterphenyl ring A monovalent group derived from an aromatic hydrocarbon ring such as
Furan ring, benzofuran ring, thiophene ring, benzothiophene ring, pyrrole ring, pyrazole ring, imidazole ring, oxadiazole ring, indole ring, carbazole ring, pyrroloimidazole ring, pyrrolopyrazole ring, pyrrolopyrrole ring, thienopyrrole ring, thienothiophene Ring, furopyrrole ring, furofuran ring, benzofuran ring, benzisoxazole ring, benzisothiazole ring, benzimidazole ring, benzimidazole ring, pyridine ring, pyrazine ring, pyridazine ring, pyrimidine ring, triazine ring, quinoline ring, isoquinoline ring, cinnoline ring, quinoxaline A monovalent group derived from an aromatic heterocycle such as a ring, a phenanthridine ring, a perimidine ring, a quinazoline ring, a quinazolinone ring and an azulene ring;
Can be mentioned.

Among them, a monovalent group derived from a benzene ring, a naphthalene ring, a fluorene ring, a biphenyl ring, a pyridine ring or a carbazole ring is more preferable because the negative charge is efficiently delocalized, the stability and the heat resistance are excellent. Particularly preferred is a benzene ring (phenyl group) or a biphenyl ring (biphenyl group).

Ar ¹⁰⁰ may be further substituted by another substituent without departing from the spirit of the present invention. The substituent which Ar ¹⁰⁰ may have is a halogen atom, a cyano group, an aromatic ring group consisting of 1 to 5 aromatic rings, an aliphatic hydrocarbon ring group, an alkyl group, an alkenyl group, an alkynyl group, an aralkyl group, an alkyl group It is an oxy group, an aryloxy group, an alkylthio group, an arylthio group, an alkyl ketone group or an aryl ketone group. In these substituents, adjacent substituents may be combined to form a ring.

As an example of a halogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom etc. are mentioned, A fluorine atom is preferable from the stability of a compound. It is particularly preferable that four or more fluorine atoms are substituted from the viewpoint of the stability of the compound.

Examples of the aromatic ring group consisting of 1 to 5 aromatic rings include phenyl group, biphenyl group, terphenyl group, quaterphenyl group, naphthyl group, phenanthrenyl group, triphenylene group, naphthylphenyl group and the like, and phenyl group and biphenyl Preferred is a group, a terphenyl group or a quaterphenyl group from the stability of the compound.

Examples of the aliphatic hydrocarbon ring group include cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group and the like.

Examples of the alkyl group include a methyl group, an ethyl group, a branched or linear propyl group, a butyl group, a hexyl group, an octyl group and a decyl group.
Examples of alkenyl groups include vinyl, propenyl, butenyl and the like.
Examples of the alkynyl group include acetyl group, propynyl group, butynyl group and the like.
Examples of the aralkyl group include benzyl group, phenylethyl group, phenylhexyl group and the like.

Examples of the alkyloxy group include a methoxy group, an ethoxy group, a butyloxy group, a hexyloxy group, an octyloxy group and the like.
Examples of the aryloxy group include phenoxy group and naphthyloxy group.
Examples of the alkylthio group include methylthio group, ethylthio group, butylthio group, hexylthio group and the like.
Examples of the arylthio group include phenylthio group, naphthylthio group and the like.
Examples of the alkyl ketone group include an acetyl group, an ethyl carbonyl group, a butyl carbonyl group, an octyl carbonyl group and the like.
Examples of the aryl ketone group include benzoyl group, naphthylcarbonyl group and the like.

When adjacent substituents combine to form a ring, examples of the ring formed include a cyclobutene ring, a cyclopentene ring and the like.

In addition, these substituents may be further substituted with a substituent, and examples of the substituent include a halogen atom, an alkyl group or an aryl group.
Among these substituents, a halogen atom or an aryl group is preferable in terms of the stability of the compound. Most preferably, it is a halogen atom.

The fluorine-substituted alkyl group for Ar ¹⁰⁰ is preferably a linear or branched alkyl group having 1 to 12 carbon atoms, which is substituted with a fluorine atom, more preferably a perfluoroalkyl group, and having 1 carbon atom. A linear or branched perfluoroalkyl group of -5 is more preferable, a linear or branched perfluoroalkyl group having 1 to 3 carbon atoms is particularly preferable, and a perfluoromethyl group is most preferable. The reason for this is that the coating film using the electron accepting compound AC and the coating film laminated on the upper layer become stable.

Ar ^{100 in the} formula (101) is preferably substituted by four or more fluorine atoms in terms of the stability of the compound.

The counter anion structure more preferable as the counter anion represented by the above formula (106) is represented by the following formula (109).

[In the formula (109), Ar ¹⁰¹ to Ar ¹⁰⁴ each independently represent an aromatic ring group which may have a substituent, and are the same as Ar ^{100 in the} formula (106). ]

The same applies to Ar ¹⁰¹ to Ar ¹⁰⁴ in the description of Ar ¹⁰⁰ below. Ar ¹⁰¹ to Ar ¹⁰⁴ are preferably aromatic ring groups having 30 or less carbon atoms. Expression (109) represents the case where p = 0 and g = 1 in expression (106).

Moreover, it is also preferable that at least one of Ar ¹⁰⁰ is represented by the following formula (103).
More preferably, Ar ¹⁰⁰ is all represented by the following formula (103).

[In formula (103), Ar ¹⁰⁷ is a substituent, and F ₄ represents that four fluorine atoms are substituted. ]

Ar ¹⁰⁷ is the same as a group preferable as a substituent which the aforementioned Ar ¹⁰⁰ may have. Further, F ₄ represents the fluorine atom is four substituents.
Among these, Ar ¹⁰⁷ is more preferably represented by the following formula (104). ]

In addition, it is preferable that at least one of Ar ¹⁰⁰ be represented by a substituent comprising a structure represented by the following general formula (107) or (108).

[In formulas (107) and (108), an asterisk (*) represents a bond. ]
These formula (107), the structure represented by the formula (108) may have a substituent, examples of the substituent are the same as substituent which may be Ar ¹⁰⁰ is not.

Since the structures represented by these formulas (107) and (108) have crosslinkability and it is expected that the electron accepting compound AC or its decomposition product will not diffuse to other layers, the device efficiency is improved. There is expected.

The molecular weight of the counter anion of the electron accepting compound AC is usually 700 or more, preferably 900 or more, more preferably 1100 or more, and usually 6000 or less, preferably 4000 or less, more preferably 3000 or less. If the molecular weight of the counter anion is too small, the negative charge delocalization will be insufficient, the interaction with the cation may be strong, and the charge transport ability may decrease. If the molecular weight of the counter anion is too large, the counter anion may The anion itself may interfere with charge transport.

Specific examples of the counter anion are given below, but the counter anion of the electron accepting compound AC is not limited to these.

(Cation counter)
In the formula (101), A ⁺ is a counter cation of the electron accepting compound AC.
As the counter cation, an iodonium cation, a sulfonium cation, a carbocation, an oxonium cation, an ammonium cation, a phosphonium cation, a cycloheptyllyenyl cation or a ferrocenium cation having a transition metal is preferable, and an iodonium cation, a sulfonium cation, a carbocation, Ammonium cations are more preferred, and iodonium cations are particularly preferred.

As the iodonium cation, a cation represented by the following formula (102) is preferable.

[In formula (102), Ar ¹⁰⁵ and Ar ¹⁰⁶ each independently represent an aromatic ring group which may have a substituent. ]

The aromatic ring group is the same as the aromatic ring group in Ar ¹⁰⁰ of the above formula (106). Preferred examples of the aromatic ring group include phenyl group, biphenyl group, terphenyl group, quaterphenyl group, naphthyl group, phenanthrenyl group, triphenylene group, and naphthylphenyl group, and the like, and a phenyl group is most preferable from the stability of the compound.

The aromatic ring group exemplified as Ar ¹⁰⁵ and Ar ¹⁰⁶ may be further substituted by another substituent. The type of the substituent is not particularly limited, and any substituent is applicable.
Preferred examples of the substituent which Ar ¹⁰⁵ and Ar ¹⁰⁶ may have are a halogen atom, an aromatic ring group consisting of 1 to 5 aromatic rings, an aliphatic hydrocarbon ring group, an alkyl group, an aralkyl group, an alkyloxy group, Among them, an aryloxy group and a hydroxy group, among which an alkyl group is particularly preferable in order to improve the solubility in a solvent.

Examples of the halogen atom include fluorine atom, chlorine atom, bromine atom and iodine atom.

Examples of the aromatic ring group consisting of 1 to 5 aromatic rings include phenyl group, biphenyl group, terphenyl group, quaterphenyl group, naphthyl group, phenanthrenyl group, triphenylene group, naphthylphenyl group and the like, and phenyl group Is preferred from the stability of the compound.

Examples of the alkyl group include a methyl group, an ethyl group, a branched or linear propyl group, a butyl group, a hexyl group, an octyl group and a decyl group.
Examples of the aralkyl group include benzyl group, phenylethyl group, phenylhexyl group and the like.
Examples of the alkyloxy group include a methoxy group, an ethoxy group, a butyloxy group, a hexyloxy group, an octyloxy group and the like.
Examples of the aryloxy group include phenoxy group and naphthyloxy group.

In addition, these substituents may be further substituted with a substituent, and examples of the substituent include a halogen atom, an alkyl group or an aryl group.
Among these substituents, an alkyl group is preferable in view of film stability.

The counter cation represented by the above formula (102) is particularly preferably represented by the following formula (105).

[In Formula (105), Ar ¹⁰⁸ and Ar ¹⁰⁹ are the same as the substituents that Ar ¹⁰⁵ and Ar ¹⁰⁶ may have in Formula (102) described above. ]

(Molecular weight)
The molecular weight of the electron accepting compound AC is usually 900 or more, preferably 1000 or more, more preferably 1200 or more, and usually 10000 or less, preferably 5000 or less, more preferably 3000 or less. If the molecular weight of the electron accepting compound AC is too small, delocalization of the positive charge and the negative charge may be insufficient, and the electron accepting ability may decrease. If the molecular weight of the electron accepting compound AC is too large, The electron accepting compound itself may interfere with charge transport.

<Electron Acceptable Compound Having Crosslinking Group>
The electron accepting compound is preferably an electron accepting compound having a crosslinking group.

The mother skeleton of the electron accepting compound is not particularly limited, but is preferably an electron accepting ionic compound which is an ionic compound, and preferably has a crosslinking group in the counter anion. More preferably, it is an electron accepting ionic compound having a counter anion represented by the above formula (106), particularly preferably an electron accepting property comprising a non-coordinating anion represented by the above formula (101) and a cation Compound AC.

When the electron accepting compound having a crosslinking group is an ionic compound, the counter cation is a ferrocenium having an iodonium cation, a sulfonium cation, a carbocation, an oxonium cation, an ammonium cation, a phosphonium cation, a cycloheptitrilienyl cation or a transition metal. And represent iodonium cations, more preferably iodonium cations, sulfonium cations, carbocations, ammonium cations, particularly preferably iodonium cations.
The iodonium cation is preferably a structure represented by the above formula (102), and more preferable structures are also the same.

The crosslinking group which may be possessed by Ar ^{100 of the} formula (101) and the crosslinking group which may be possessed by the electron accepting ion compound are preferably selected from the following crosslinking group group Z. Since these crosslinking groups crosslink at a temperature sufficiently higher than room temperature, they have high stability as a composition for a charge transport film, and since the crosslinking bonds have high stability against oxidation and reduction, they can be used as organic electroluminescent devices. Stability is also considered to be high.

[Crosslinking group group Z]

[The asterisk (*) in formulas (Z-1) to (Z-7) represents a bond. ]

Formulas (Z-1) to (Z-7) may further have an optional substituent. Preferred examples of the substituent include groups derived from cyclic or noncyclic aliphatic hydrocarbon having 30 or less carbon atoms, aryl groups having 30 or less carbon atoms, alkyloxy groups having 30 or less carbon atoms, aralkyl groups having 30 or less carbon atoms, and the like. It can be mentioned.

In addition, the substituents of the bridging group represented by Formula (Z-1) and Formula (Z-2) may be such that the substituents are bonded to each other to form a ring.
The crosslinking groups represented by formulas (Z-3) to (Z-7) preferably have no substituent.

Among the above-mentioned crosslinking groups, the crosslinking groups represented by formulas (Z-1) to (Z-4) are preferable in that the stability after crosslinking is high and the device driving life is improved, and the formula (Z-1) or The crosslinking group represented by (Z-2) is particularly preferred. The crosslinking group represented by the formula (Z-1) is more preferably a structure represented by the above formula (107), and the preferable substituent which may be contained is a cyclic or non-cyclic aliphatic carbon having at most 30 carbon atoms More preferably, they are a group derived from hydrogen and an aryl group having a carbon number of 30 or less, and have no substituent.
The crosslinking group represented by the formula (Z-2) is more preferably a structure represented by the above formula (108), and a preferable substituent which may be contained is a cyclic or non-cyclic aliphatic carbon having at most 30 carbon atoms More preferably, they are a group derived from hydrogen and an aryl group having a carbon number of 30 or less, and have no substituent.

When the electron accepting ion compound has a crosslinking group represented by Formula (Z-1) or Formula (Z-2), it can be used as Compound A of the present invention represented by Formula (4).
When the electron accepting compound is used as the compound A in the present invention, the electron accepting compound is a compound having the formula (107), formula (108), formula (Z-1) or formula (Z-) as a crosslinking group. It is particularly preferable to have a crosslinking group represented by 2). The reason is the same as the reason why it is preferable that the compound A has a crosslinking group which is the formula (6) or the formula (7).

The reason why the crosslinking group is preferably bonded to the counter anion of the electron accepting ionic compound is as follows.
That is, when the electron accepting ionic compound and the hole transporting compound described later are coexisted in the composition, the electron accepting ionic compound withdraws electrons from the hole transporting compound, and as a result, the electron accepting ionic compound The counter anion and the cation radical of the hole transporting compound are generated, and the counter anion of the electron accepting ion compound and the cation radical of the hole transporting compound form an ion pair. This corresponds to the charge transporting ionic compound described later. When the electron accepting ionic compound has a crosslinking group, the charge transporting ionic compound is stabilized due to the counter anion being further bonded to the hole transporting compound having the crosslinking group by the crosslinking group, and the durability is improved. It is thought that the driving life of the organic electroluminescent device is improved. Furthermore, since the counter anion of the electron accepting ionic compound bound to the hole transporting compound is not liberated, it is considered that the diffusion of the counter anion of the electron accepting ionic compound to the light emitting layer is suppressed and the light emission efficiency is improved. . In addition, even when the counter anions of the electron accepting ionic compound are cross-linked, the molecular weight is increased by the cross-linking, which is preferable because it becomes difficult to diffuse. In addition, even when counter anions of a plurality of electron accepting ionic compounds are cross-linked, the probability that at least one cross-linking group cross-links with the cross-linking group of the hole transporting compound is high, and a plurality of electron accepting properties The cluster in which the counter anions of the ionic compound are crosslinked does not diffuse as it is crosslinked with the hole transporting compound, which is preferable.

The number of crosslinking groups in the electron accepting compound having a crosslinking group is preferably 4 or less in one molecule. Within this range, the amount of crosslinking groups remaining without crosslinking reaction is small, and the organic electroluminescent device produced using the electron accepting compound having a crosslinking group is stable. More preferably, the number is 3 or less in one molecule because the number of crosslinking groups remaining without crosslinking reaction is further reduced.

<Specific Example of Electron Accepting Ion Compound>
Specific examples of the electron accepting ionic compound are listed below, but the electron accepting ionic compound according to the present invention is not limited thereto.

<Composition for Charge Transport Film>
The above-mentioned electron accepting ionic compound is a composition containing the electron accepting ionic compound and a charge transporting compound described later (hereinafter, appropriately referred to as “composition for charge transporting film (A)”), or described later. A composition containing a charge transportable ionic compound comprising a cation radical of the charge transportable compound and a counter anion which is a part of the electron accepting ionic compound (hereinafter referred to as “the composition for charge transport film (B)” as appropriate It is preferable to use as.). Here, for the sake of convenience, the composition for charge transport film (A) and the composition for charge transport film (B) will be described separately, but the composition for charge transport film is the above-mentioned electron accepting ion compound, charge matrix described later Also included are compositions comprising a transportable compound and a charge transportable ionic compound comprising a cation radical of the charge transportable compound described below and a counter anion which is part of the aforementioned electron accepting ionic compound.

The compositions (A) and (B) for charge transport film are compositions (composition for charge transport material) which can be widely used for the use of the charge transport material. However, in order to form this into a film normally and to use as a charge transport material film, ie, a "charge transport film", it shall be called "the composition for charge transport films" especially in this specification.

In the present invention, the charge transporting compound is usually a hole transporting compound. Therefore, in the present specification, unless otherwise specified, the hole transporting compound can be read as a charge transporting compound.

<Hole transportable compound>
Next, a hole transporting compound (hereinafter, appropriately referred to as “the hole transporting compound of the present invention” as needed) as a charge transporting compound contained in the composition for charge transporting film will be described.

The hole transporting compound preferably has a crosslinking group. This is because the film can be insolubilized by crosslinking the hole transporting compound after the film formation, and it becomes possible to coat and form another layer on the film. Preferred crosslinking groups are the crosslinking groups mentioned in the above-mentioned bridging group group Z, and preferred structures among these are also the same as in the above-mentioned bridging group group Z.

When the hole transporting compound has a crosslinking group, it is preferably a crosslinking group capable of performing a crosslinking reaction with the crosslinking group of the electron accepting compound, and more preferably, the site to be crosslinked is the crosslinking of the crosslinking group of the electron accepting compound It is a crosslinking group having the same structure as the reaction site.
The hole transporting compound is that the hole transporting compound and the electron accepting compound each have a crosslinking group, and the crosslinking group of the hole transporting compound and the crosslinking group of the electron accepting compound can be cross-linked with each other. The electron accepting compound is immobilized on the substrate, and diffusion of the electron accepting compound to other layers is suppressed, which is preferable. In particular, by suppressing the diffusion of the electron accepting compound into the light emitting layer, quenching of excitons in the light emitting layer is suppressed, and the light emission efficiency is improved, which is preferable.

As the hole transporting compound, a compound having an ionization potential of 4.5 eV to 5.5 eV is preferable from the viewpoint of the hole transporting ability. Examples include aromatic amine compounds, phthalocyanine derivatives or porphyrin derivatives, oligothiophene derivatives and the like. Among them, aromatic amine compounds are preferable from the viewpoint of amorphousness, solubility in solvents, and visible light transmittance.

Among the aromatic amine compounds, aromatic tertiary amine compounds are particularly preferable in the present invention. The aromatic tertiary amine compound in the present invention is a compound having an aromatic tertiary amine structure, and also includes a compound having a group derived from an aromatic tertiary amine.

The type of the aromatic tertiary amine compound is not particularly limited, but from the viewpoint of the surface smoothing effect, an aromatic tertiary amine polymer which is a polymer compound having a weight average molecular weight of 1,000 or more and 1,000,000 or less Compounds are further preferred.
As an aromatic tertiary amine compound, what contains the structural unit represented by above-mentioned Formula (3) is preferable.

The molecular weight of these hole transporting compounds is usually 5000 or less, preferably 3000 or less, more preferably 2000 or less, still more preferably 1700 or less, except in the case of the polymer compound having the specific repeating unit described above. And particularly preferably in the range of 1400 or less, usually 200 or more, preferably 400 or more, more preferably 600 or more. When the molecular weight of the hole transporting compound is too high, synthesis and purification are difficult and not preferable. When the molecular weight is too low, the heat resistance may be lowered, which is also not preferable.

The composition for charge transport film (A) may contain any one kind of the above-mentioned hole transportable compounds alone, or may contain two or more kinds. When two or more hole transporting compounds are contained, the combination thereof is optional, but one or two or more kinds of aromatic tertiary amine polymer compounds and one or two kinds of other hole transporting compounds It is preferable to use the above in combination. As a kind of the hole transporting compound used in combination with the above-mentioned polymer compound, an aromatic amine compound is preferable.

The content of the hole transporting compound in the composition for charge transport film (A) is set to be in the range satisfying the ratio to the electron accepting compound described later. When two or more charge transport film compositions are used in combination, the total content of these is made to fall within the range described later.

<Composition for Charge Transport Film (A)>
The composition (A) for charge transport film comprises at least an electron accepting compound described in detail in the section of <electron accepting compound>, and a hole transporting compound described in detail in the section of <hole transporting compound> Prepared by mixing The electron accepting compound may contain one kind alone, or may contain two or more kinds in any combination and ratio. The same applies to the hole transporting compound.

The content of the electron accepting compound in the composition for charge transport film (A) is usually 0.1% by mass or more, preferably 1% by mass or more, and usually 100% by mass or less, based on the value with respect to the hole transporting compound. Preferably, it is 40 mass% or less. If the content of the electron accepting compound is at least the above lower limit, free carriers (cation radicals of the hole transporting compound) can be sufficiently generated, and if it is at most the above upper limit, sufficient charge transporting ability can be secured. . When two or more electron accepting compounds are used in combination, the total content of these is made to fall within the above range. The same applies to the hole transporting compound.

<Composition for Charge Transport Film (B)>
The composition (B) for charge transport film is, as described above, a composition containing a charge transport ionic compound comprising the cation radical of the above-mentioned hole transport compound and the counter anion of the above-mentioned electron accepting ionic compound. .

The cation radical of the charge transport compound, which is the cation of the charge transport ionic compound, is a chemical species obtained by removing one electron from the electrically neutral compound shown in the above-mentioned <hole transport compound>. However, when the hole transporting compound is a polymer compound, it is a chemical species including a partial structure in which one electron is removed from the electrically neutral partial structure in the polymer structure.
In particular, it is an aromatic tertiary amine compound having a partial structure represented by the following formula (110) that the cation radical of the hole transporting compound has an appropriate redox potential, and a stable charge transporting ion It is preferable from the point which a compound is obtained.

[In the above formula (110), q represents an integer of 1 to 5; Ar ⁸¹ to Ar ⁸⁴ each independently represent a C6-C30 aromatic hydrocarbon group which may have a substituent, or R represents an aromatic heterocyclic group having 3 to 30 single atoms which may have a substituent, and R ⁸¹ to R ⁸⁴ each independently represent a substituent. ]

Ar ⁸¹ to Ar ⁸⁴ are preferably aromatic hydrocarbon groups, and specific examples thereof, examples of preferable groups, examples of substituents which may be possessed and examples of preferable substituents are Ar ¹⁰⁰ in the above formula (106). And particularly preferably an aromatic hydrocarbon group having 6 to 14 carbon atoms which may have a substituent.

Preferred substituents and preferred R ⁸¹ to R ⁸⁴ are groups selected from the above-mentioned Substituent Group W, preferably unsubstituted or an alkyl group of Substituent Group W or an aromatic hydrocarbon group. .
Preferably, q is 3 or less, more preferably 2 or less, and particularly preferably 1, from the viewpoint that the partial structure represented by formula (110) tends to be a cation radical.

The aromatic tertiary amine compound having a partial structure represented by the formula (110) is a low molecular weight compound having only one or a plurality of partial structures represented by the formula (110) as an aromatic tertiary amine structure, It is also good.
The aromatic tertiary amine compound having a partial structure represented by formula (110) may be a polymer compound having a plurality of partial structures represented by formula (110).

When the aromatic tertiary amine compound having a partial structure represented by the formula (110) is a polymer compound, one of Ar ^{81 and} Ar ⁸² or one of Ar ^{83 and} Ar ⁸⁴ is high. It may be bonded to the molecular structure, or it may be linked to the main chain of the polymer compound by both Ar ⁸¹ or Ar ⁸² and either Ar ⁸³ or Ar ⁸⁴ .

When the aromatic tertiary amine compound having a partial structure represented by the formula (110) is a polymer compound, either one of Ar ⁸¹ or Ar ⁸² and either one of Ar ⁸³ or Ar ⁸⁴ are used. Preferably, it is a polymer compound linked to the main chain of the polymer compound.

In addition, the cation radical of the hole transporting compound is a chemical species having a structure in which one electron is removed from a repeating unit of an aromatic tertiary amine polymer compound having a weight average molecular weight of 1000 or more and 1000000 or less. It is preferable from the point of film formability. To remove one electron from the repeating unit of the aromatic tertiary amine polymer compound is to remove one electron from part or all of a plurality of repeating units contained in the aromatic tertiary amine polymer compound. The aromatic tertiary amine polymer compound is preferred because it is stable to remove one electron from a part of the plurality of repeating units contained in the aromatic tertiary amine polymer compound. Examples of the aromatic tertiary amine polymer compound include those described in the above-mentioned <hole transporting compound>. The preferred examples are also the same as described above.

<Charge Transportable Ion Compound>
The charge transporting ionic compound is a compound in which the cation radical of the charge transporting compound described above and the counter anion which is a part of the electron accepting ionic compound are ionically bonded.
The charge transporting ionic compound can be obtained by mixing the electron accepting ionic compound and the hole transporting compound, and dissolves easily in various solvents.
The molecular weight of the charge transporting ionic compound is usually 1000 or more, preferably 1200 or more, more preferably 1400 or more, and usually 9000 or less, preferably 5000 or less, more preferably, except when the cation radical is a polymer compound. Is in the range of 4000 or less.

<Method of Preparing Composition for Charge Transport Film (B)>
The charge transporting ionic compound (B) is preferably prepared by dissolving an electron accepting ionic compound and a hole transporting compound in a solvent and mixing them. In this solution, the hole-transporting compound is oxidized by the electron-accepting ionic compound to be cation radicalized, and the charge is an ionic compound of the counter anion of the electron-accepting ionic compound and the cation radical of the hole-transporting compound Transportable ion compounds are formed.

At this time, the hole transporting compound is preferably an aromatic tertiary amine compound. Mixing in the solution increases the probability that the electron accepting ionic compound is present in the vicinity of the amine structure which is a site susceptible to oxidation of the aromatic tertiary amine compound, and the aromatic tertiary amine compound by the electron accepting ionic compound Is oxidized to form a cation radical, which easily generates an ionic compound of the counter anion of the electron accepting ionic compound and the cation radical of the aromatic tertiary amine compound. At this time, it is preferable to heat the solution from the viewpoint of promoting the reaction.

It is also preferable to prepare a mixture of an electron accepting ionic compound and a hole transporting compound by heating. The mixture is preferably a film formed by applying a solution obtained by dissolving a mixture of an electron accepting ion compound and a hole transporting compound in a solvent. By heating the mixture, the electron accepting ionic compound and the hole transporting compound diffuse into each other in the mixture, and the electron accepting compound is present in the vicinity of the amine structure which is a site susceptible to oxidation of the aromatic tertiary amine compound. The probability of occurrence is high, and it is easy to form an ionic compound of the counter anion of the electron accepting ionic compound and the cation radical of the aromatic tertiary amine compound.

The composition for charge transport film (B) may contain one kind of the charge transport ion compound described above alone, or may contain two or more kinds. The charge transporting ionic compound is preferably contained singly or in combination, and more preferably contained singly. This is because the variation in ionization potential of the charge transportable ionic compound is small and the hole transportability is excellent.

The composition containing one charge transportable ionic compound alone or two or more is a composition prepared by using only two or three combinations of the electron accepting ionic compound and the hole transportable compound in total. A composition prepared using at least one electron accepting ionic compound and at least one hole transporting compound.

The composition for charge transport film (B) preferably contains, in addition to the charge transport ionic compound, the hole transport compound described in <Hole transport compound>. The content of the hole transporting compound in the composition for charge transport film (B) is preferably 10% by mass or more, more preferably 20% by mass or more, more preferably 30% by mass or more, in terms of the value with respect to the charge transporting ionic compound. The content is preferably not less than 10% by mass, more preferably not more than 10000% by mass, and still more preferably not more than 1000% by mass.

The charge transport film formed from the composition (B) for charge transport film has high hole injection / transport ability by transferring positive charge from the charge transport ionic compound to the nearby neutral hole transport compound. It is preferable that the charge transporting ionic compound and the neutral hole transporting compound have a mass ratio of about 1: 100 to 100: 1, and a ratio of about 1:20 to 20: 1. It is further preferred that

<Solvent, etc.>
The composition for charge transport film (A) may contain other components, such as a solvent and various additives, as necessary, in addition to the above-mentioned electron accepting ionic compound and hole transporting compound. In particular, when the charge transport film is formed by a wet film formation method using the composition for charge transport film according to the present invention, the solvent is used to dissolve the electron accepting ion compound and the hole transport compound described above. It is preferable to make it be in the state of being made to be.

Here, the charge transporting ionic compound is generated by mixing the electron accepting ionic compound and the hole transporting compound. That is, the charge transporting ionic compound is a compound derived from the electron accepting ionic compound and the hole transporting compound. For this reason, the composition for charge transport film (B) containing the charge transport ion compound may contain other components as necessary as the composition for charge transport film (A), and it is possible to form a wet film When the charge transport film is formed by the film method, it is preferable to use a solvent to dissolve the charge transport ionic compound.

The type of the solvent contained in the composition for charge transport film (A) is not particularly limited as long as it can dissolve both the electron accepting ionic compound and the hole transporting compound described above. Further, the type of the solvent contained in the composition for charge transport film (B) is not particularly limited as long as it is a solvent capable of dissolving the charge transport ion compound. Here, the solvent for dissolving the above-mentioned electron accepting ionic compound and the above hole transporting compound is usually 0.005% by mass or more of the hole transporting compound, preferably 0.5% by mass or more, more preferably Is a solvent that dissolves 1% by mass or more, and is a solvent that dissolves the electron accepting ionic compound usually 0.001% by mass or more, preferably 0.1% by mass or more, more preferably 0.2% by mass or more . Since the aforementioned electron accepting ionic compounds have high solubility, various solvents can be applied. Further, the solvent for dissolving the charge transporting ionic compound is a solvent which dissolves the charge transporting ionic compound usually in an amount of 0.001% by mass or more, preferably 0.1% by mass or more, more preferably 0.2% by mass or more. is there.

In addition, as the solvent contained in the composition (A) for charge transport film, an electron accepting compound, a hole transporting compound, and a deactivating substance which may inactivate free carriers (cationic radicals) generated from a mixture thereof Or what does not contain what generate | occur | produces a deactivating substance is preferable. Similarly, the solvent contained in the composition for charge transport film (B) is preferably a solvent which does not contain a deactivating substance which may inactivate the charge transporting ionic compound or a substance which generates a deactivating substance.

Since the electron accepting ionic compound, the hole transporting compound, the free carrier (cation radical) generated from the mixture thereof, and the charge transporting ionic compound are thermodynamically and electrochemically stable, various solvents may be used. It is possible to use. As preferable solvents, for example, ether solvents and ester solvents can be mentioned. Specifically, as ether solvents, for example, aliphatic ethers such as ethylene glycol dimethyl ether, ethylene glycol diethyl ether, propylene glycol-1-monomethyl ether acetate (PGMEA); 1,2-dimethoxybenzene, 1,3 And aromatic ethers such as dimethoxybenzene, anisole, phenetole, 2-methoxytoluene, 3-methoxytoluene, 4-methoxytoluene, 2,3-dimethylanisole, 2,4-dimethylanisole and the like. As ester solvents, for example, aliphatic esters such as ethyl acetate, n-butyl acetate, ethyl lactate and n-butyl lactate; phenyl acetate, phenyl propionate, methyl benzoate, ethyl benzoate, propyl benzoate, benzoic acid and aromatic esters such as n-butyl. Any of these may be used alone, or two or more may be used in any combination and ratio.

When a solvent is used, the concentration of the solvent with respect to the charge transport film compositions (A) and (B) is usually 10% by mass or more, preferably 30% by mass or more, more preferably 50% by mass or more, and usually 99 .999 mass% or less, preferably 99.99 mass% or less, more preferably 99.9 mass% or less. In addition, when mixing and using 2 or more types of solvent, it is made for the sum total of these solvent to satisfy | fill this range.

Since the organic electroluminescent element is formed by laminating a plurality of layers composed of organic compounds, it is required that each layer be a uniform layer. In the case of forming a constituent layer of an organic electroluminescent element by a wet film forming method using the composition (A) or (B) for charge transport film, water is present in a solution for forming a thin film (composition for charge transport film) Then, water is mixed into the coating film and the uniformity of the film is impaired, so the water content in the solution is preferably as small as possible. Further, in general, a material that is significantly deteriorated by moisture such as a cathode is often used in the organic electroluminescent device, and therefore the presence of moisture is not preferable also from the viewpoint of the deterioration of the device.

Specifically, the amount of water contained in the compositions (A) and (B) for charge transport film is usually suppressed to 1% by mass or less, preferably 0.1% by mass or less, and further 0.05% by mass or less. preferable.
Examples of the method for reducing the amount of water in the composition include a nitrogen gas seal, use of a desiccant, dehydration of the solvent in advance, and use of a solvent with low water solubility. Among them, it is preferable to use a solvent having a low solubility of water from the viewpoint of preventing the phenomenon in which the solution coating film absorbs moisture in the air and whitening during the coating step.

When used for film formation by a wet film formation method, the compositions (A) and (B) for charge transport film are solvents having low water solubility, specifically, for example, 1 mass of water at 25 ° C. It is preferable to contain a solvent having a% or less, preferably 0.1% by mass or less, at a concentration of usually 10% by mass or more, particularly 30% by mass or more, particularly 50% by mass or more, based on the whole composition.
In addition, as a component which the composition for charge transport films (A) and (B) may contain, binder resin, a coatability improvement agent, etc. are mentioned. The type and content of these components may be appropriately selected according to the application of the composition for charge transport film.

<Relationship between Composition for Charge Transport Film (A) and (B)>
The charge transport film formed of the composition for charge transport film (A) is excellent in heat resistance and has high hole injecting / transporting ability. The reason why such excellent characteristics can be obtained will be described below.

The composition for charge transport film (A) contains the electron accepting compound and the hole transporting compound described above. The cation in the electron accepting ion compound has a central atom of hypervalent, and its positive charge is widely delocalized, and thus has high electron accepting property. As a result, electron transfer occurs from the hole transporting compound to the cation of the electron accepting ionic compound, and a charge transporting ionic compound composed of the cation radical and the counter anion of the hole transporting compound is generated. Since the cation radical of this hole transportable compound becomes a carrier of charge, the electrical conductivity of the charge transport film can be increased. That is, when the composition for charge transport film (A) is prepared, it is considered that a charge transportable ionic compound is formed at least partially including the cation radical of the hole transport compound and the counter anion of the electron accepting ionic compound.

For example, when electron transfer occurs from the hole transporting compound represented by the following formula (17) to the electron accepting compound represented by the formula (1 ′), the hole transporting property represented by the formula (18) cation radical and a counter anion J compounds ^- charge transporting ionic compound consisting generated.

In addition, the electron accepting ionic compound, particularly the electron accepting compound AC, is a charge transporting ionic compound comprising the cation radical and the counter anion of the hole transporting compound efficiently without being easily sublimed or decomposed. It has the feature of generating Due to these characteristics, the electron accepting ionic compound and the charge transporting ionic compound comprising the cation radical of the hole transporting compound and the counter anion of the electron accepting ionic compound exhibit excellent heat resistance and electrochemical durability. Do. As a result, the heat resistance and the electrochemical durability of the composition for charge transport film are also improved.

Further, the composition (B) for charge transport film of the present invention contains a charge transportable ionic compound which is excellent in heat resistance and electrochemical durability. As a result, the composition for charge transport film (B) is excellent in heat resistance and electrochemical durability.

As described above, the charge transport film formed of the composition (A) or (B) for charge transport film and the charge transport film containing the charge transport ionic compound have excellent heat resistance, high hole injection / transport ability and In addition, it is preferable to use as a material of the organic electroluminescent device, and in particular, it is preferably used in applications for forming the charge transport layer of the organic electroluminescent device, and among them, the anode of the organic electroluminescent device and the light emitting layer By forming an interposing layer, in particular, a hole injection layer, the electrical connection between the anode and the hole transport layer or the light emitting layer is improved, and the driving voltage is lowered and the stability in continuous driving is also improved. .

When the charge transport film formed of the composition (A) or (B) for charge transport film is used for various applications, it is preferable to be formed into a film. The method used for film formation is not particularly limited, but since the electron accepting compound and the charge transporting ionic compound have excellent solubility in a solvent, they can be suitably used for thin film formation by a wet film forming method.

In particular, when the charge transport film is formed using the compositions (A) and (B) for charge transport film, it is possible to heat and dry at a high temperature during film formation, and the simplicity of the manufacturing process and the device characteristics Stability can be improved. In particular, when forming a hole injection layer of an organic electroluminescent device by a wet coating method, it becomes possible to heat and dry at a high temperature, which is useful as a method for reducing the amount of water in a coating, significantly degrading the organic electroluminescent device It is possible to reduce the presence of moisture and residual solvent that cause the Further, since the charge transport film formed of the composition for charge transport film (A) or (B) has high heat resistance, the heat resistance of the manufactured organic electroluminescent device is also greatly improved.

[Suitable light emitting layer forming material]
The light emitting layer contains a light emitting material and a charge transport material. The light emitting material may be a phosphorescent light emitting material or a fluorescent light emitting material. It is preferable that the light emitting material be a phosphorescent light emitting material because the light emitting efficiency is high. More preferably, the red light emitting material and the green light emitting material are phosphorescent light emitting materials, and the blue light emitting material is a fluorescent light emitting material.

<Phosphorescent light emitting material>
The phosphorescent material refers to a material that emits light from an excited triplet state. For example, a metal complex compound having Ir, Pt, Eu, etc. is a typical example, and a material containing a metal complex is preferable as a structure of the material.

Among metal complexes, as a phosphorescent organic metal complex which emits light via a triplet state, a long period periodic table (hereinafter referred to as “periodic table” unless otherwise noted, a long period periodic table And Werner type complexes or organometallic complex compounds containing a metal selected from Groups 7 to 11 as a central metal. As such a phosphorescent light emitting material, for example, the phosphorescent light emitting materials described in WO 2014/024889, WO 2015-087961, WO 2016/194784 and JP 2014-074000 can be mentioned. . Preferably, a compound represented by the following formula (201) or a compound represented by the following formula (205) is preferable, and more preferably a compound represented by the following formula (201).

In Formula (201), ring A1 represents an aromatic hydrocarbon ring structure which may have a substituent or an aromatic heterocyclic structure which may have a substituent.
Ring A2 represents a heteroaromatic ring structure which may have a substituent.
R ²⁰¹ and R ²⁰² each independently represent a structure represented by formula (202), and “*” represents that it is bonded to ring A 1 or ring A 2. R ²⁰¹ and R ²⁰² may be the same or different, and when there are a plurality of R ²⁰¹ and R ²⁰² respectively, they may be the same or different.

Ar ²⁰¹ and Ar ²⁰³ each independently represent an aromatic hydrocarbon ring structure which may have a substituent, or an aromatic heterocyclic ring structure which may have a substituent.
Ar ²⁰² is an aromatic hydrocarbon ring structure which may have a substituent, an aromatic heterocyclic ring structure which may have a substituent, or an aliphatic hydrocarbon structure which may have a substituent Represents
The substituents bound to ring A201, the substituents bound to ring A2, or the substituents bound to ring A1 and the substituents bound to ring A2 may be mutually bound to form a ring.

B ²⁰¹ -L ²⁰⁰ -B ²⁰² represents a bidentate ligand of the anionic. B ²⁰¹ and B ²⁰² each independently represent a carbon atom, an oxygen atom or a nitrogen atom, and these atoms may be atoms constituting a ring. L ²⁰⁰ represents a single bond or a group forming a bidentate ligand with B ²⁰¹ and B ²⁰² . When there are a plurality of B ²⁰¹ -L ²⁰⁰ -B ²⁰² , they may be the same or different.

Each of i1 and i2 independently represents an integer of 0 or more and 12 or less.
i3 is an integer of 0 or more, the upper limit being a number replaceable by Ar ²⁰² .
i4 is an integer of 0 or more, the upper limit being a number replaceable by Ar ²⁰¹ .
k1 and k2 are each independently an integer of 0 or more, the upper limit being the number of substitutable rings A1 and A2.
z is an integer of 1 to 3;

(Substituent)
Unless otherwise specified, as the substituent, a group selected from the following Substituent Group S is preferable.

<Substituent group S>
· Alkyl group, preferably an alkyl group having 1 to 20 carbon atoms, more preferably an alkyl group having 1 to 12 carbon atoms, still more preferably an alkyl group having 1 to 8 carbon atoms, particularly preferably an alkyl group having 1 to 6 carbon atoms .
An alkoxy group, preferably an alkoxy group having 1 to 20 carbon atoms, more preferably an alkoxy group having 1 to 12 carbon atoms, still more preferably an alkoxy group having 1 to 6 carbon atoms.
An aryloxy group, preferably an aryloxy group having 6 to 20 carbon atoms, more preferably an aryloxy group having 6 to 14 carbon atoms, still more preferably an aryloxy group having 6 to 12 carbon atoms, particularly preferably 6 carbon atoms Aryloxy group.
A heteroaryloxy group, preferably a heteroaryloxy group having 3 to 20 carbon atoms, more preferably a heteroaryloxy group having 3 to 12 carbon atoms.
An alkylamino group, preferably an alkylamino group having 1 to 20 carbon atoms, more preferably an alkylamino group having 1 to 12 carbon atoms.
An arylamino group, preferably an arylamino group having 6 to 36 carbon atoms, more preferably an arylamino group having 6 to 24 carbon atoms.
Aralkyl group, preferably an aralkyl group having 7 to 40 carbon atoms, more preferably an aralkyl group having 7 to 18 carbon atoms, still more preferably an aralkyl group having 7 to 12 carbon atoms.
A heteroaralkyl group, preferably a heteroaralkyl group having 7 to 40 carbon atoms, more preferably a heteroaralkyl group having 7 to 18 carbon atoms,
An alkenyl group, preferably an alkenyl group having 2 to 20 carbon atoms, more preferably an alkenyl group having 2 to 12 carbon atoms, still more preferably an alkenyl group having 2 to 8 carbon atoms, particularly preferably an alkenyl group having 2 to 6 carbon atoms .
An alkynyl group, preferably an alkynyl group having 2 to 20 carbon atoms, more preferably an alkynyl group having 2 to 12 carbon atoms.
・ Aryl group, preferably an aryl group having 6 to 30 carbon atoms, more preferably an aryl group having 6 to 24 carbon atoms, still more preferably an aryl group having 6 to 18 carbon atoms, particularly preferably an aryl group having 6 to 14 carbon atoms .
· Heteroaryl groups, preferably heteroaryl groups having 3 to 30 carbon atoms, more preferably heteroaryl groups having 3 to 24 carbon atoms, still more preferably heteroaryl groups having 3 to 18 carbon atoms, particularly preferably 3 to carbon atoms 14 heteroaryl group.
An alkylsilyl group, preferably an alkylsilyl group having 1 to 20 carbon atoms in the alkyl group, more preferably an alkylsilyl group having 1 to 12 carbon atoms in the alkyl group.
An arylsilyl group, preferably an arylsilyl group having 6 to 20 carbon atoms in the aryl group, more preferably an aryl silyl group having 6 to 14 carbon atoms in the aryl group.
An alkylcarbonyl group, preferably an alkylcarbonyl group having 2 to 20 carbon atoms.
An arylcarbonyl group, preferably an arylcarbonyl group having 7 to 20 carbon atoms.

In the above groups, one or more hydrogen atoms may be replaced by fluorine atoms, or one or more hydrogen atoms may be replaced by deuterium atoms.
Unless otherwise specified, aryl is an aromatic hydrocarbon ring and heteroaryl is an aromatic heterocycle.
-Hydrogen atom, deuterium atom, fluorine atom, cyano group, or -SF ₅

Among the above Substituent Group S, preferred are an alkyl group, an alkoxy group, an aryloxy group, an arylamino group, an aralkyl group, an alkenyl group, an aryl group, a heteroaryl group, an alkylsilyl group, an arylsilyl group, and these groups Or a group in which one or more hydrogen atoms are replaced by a fluorine atom, a fluorine atom, a cyano group, or -SF ₅ ;
More preferably, it is an alkyl group, an arylamino group, an aralkyl group, an alkenyl group, an aryl group, a heteroaryl group, and a group in which one or more hydrogen atoms of these groups are replaced by a fluorine atom, a fluorine atom, cyano Or -SF ₅ and
More preferably, it is an alkyl group, an alkoxy group, an aryloxy group, an arylamino group, an aralkyl group, an alkenyl group, an aryl group, a heteroaryl group, an alkylsilyl group, an arylsilyl group,
Particularly preferred are an alkyl group, an arylamino group, an aralkyl group, an alkenyl group, an aryl group and a heteroaryl group,
Most preferably, they are an alkyl group, an arylamino group, an aralkyl group, an aryl group and a heteroaryl group.

The substituent group S may further have a substituent selected from the substituent group S as a substituent. Preferred groups, more preferred groups, further preferred groups, particularly preferred groups, and most preferred groups of the substituents which may be possessed are the same as the preferred groups in the substituent group S.

(Ring A1)
The ring A1 represents an aromatic hydrocarbon ring structure which may have a substituent or an aromatic heterocyclic ring structure which may have a substituent.

The aromatic hydrocarbon ring is preferably an aromatic hydrocarbon ring having 6 to 30 carbon atoms,
Specifically, a benzene ring, a naphthalene ring, an anthracene ring, a triphenylyl ring, an acenaphthene ring, a fluoranthene ring and a fluorene ring are preferable.

The aromatic heterocyclic ring is preferably an aromatic heterocyclic ring having a carbon number of 3 to 30, containing any of a nitrogen atom, an oxygen atom or a sulfur atom as a hetero atom, more preferably a furan ring, a benzofuran ring or a thiophene ring And benzothiophene ring.
The ring A1 is more preferably a benzene ring, a naphthalene ring or a fluorene ring, particularly preferably a benzene ring or a fluorene ring, and most preferably a benzene ring.

(Ring A2)
Ring A2 represents a heteroaromatic ring structure which may have a substituent.

The aromatic heterocyclic ring is preferably an aromatic heterocyclic ring having a carbon number of 3 to 30, containing any of nitrogen atom, oxygen atom or sulfur atom as a hetero atom, and specifically, a pyridine ring, a pyrimidine ring , Pyrazine ring, triazine ring, imidazole ring, oxazole ring, thiazole ring, benzothiazole ring, benzooxazole ring, benzoimidazole ring, quinoline ring, isoquinoline ring, quinoxaline ring, quinazoline ring, naphthyridine ring, phenanthridine ring Preferably, it is a pyridine ring, a pyrazine ring, a pyrimidine ring, an imidazole ring, a benzothiazole ring, a benzoxazole ring, a quinoline ring, an isoquinoline ring, a quinoxaline ring, a quinazoline ring, more preferably a pyridine ring, an imidazole ring, benzothiazole Ring, quinoline ring, a A quinoline ring, a quinoxaline ring, a quinazoline ring, and most preferably, a pyridine ring, an imidazole ring, a benzothiazole ring, a quinoline ring, quinoxaline ring, quinazoline ring.

(Combination of ring A1 and ring A2)
A preferred combination of the ring A1 and the ring A2 is (benzene ring-pyridine ring), (benzene ring-quinoline ring), (benzene ring-quinoxaline ring), (benzene ring-) when expressed as (ring A1-ring A2) Quinazoline ring), (benzene ring-imidazole ring), (benzene ring-benzothiazole ring).

(Substituents of ring A1 and ring A2)
The substituent which the ring A1 and the ring A2 may have can be optionally selected, but is preferably one or more types of substituents selected from the aforementioned substituent group S.

(Ar ²⁰¹ , Ar ²⁰² , Ar ²⁰³ )
Ar ²⁰¹ and Ar ²⁰³ each independently represent an aromatic hydrocarbon ring structure which may have a substituent, or an aromatic heterocyclic ring structure which may have a substituent.
Ar ²⁰² is an aromatic hydrocarbon ring structure which may have a substituent, an aromatic heterocyclic ring structure which may have a substituent, or an aliphatic hydrocarbon structure which may have a substituent Represents

When any of Ar ²⁰¹ , Ar ²⁰² and Ar ^{203 is} an aromatic hydrocarbon ring structure which may have a substituent, the aromatic hydrocarbon ring structure is preferably an aromatic ring having a carbon number of 6 to 30. Aromatic hydrocarbon ring, preferably a benzene ring, a naphthalene ring, an anthracene ring, a triphenylyl ring, an acenaphthene ring, a fluoranthene ring, a fluorene ring, more preferably a benzene ring, a naphthalene ring or a fluorene ring, most preferably a benzene ring It is.

When any of Ar ²⁰¹ and Ar ^{202 is} a benzene ring which may have a substituent, it is preferable that at least one benzene ring is bonded to an adjacent structure at an ortho position or a meta position, More preferably, two benzene rings are bonded to the adjacent structure at the meta position.

When any of Ar ²⁰¹ , Ar ²⁰² and Ar ^{203 is} a fluorene ring which may have a substituent, positions 9 and 9 ′ of the fluorene ring are bonded to a structure having a substituent or an adjacent structure Is preferred.

When any of Ar ²⁰¹ , Ar ²⁰² and Ar ^{203 is} an aromatic heterocyclic structure which may have a substituent, the aromatic heterocyclic structure is preferably a nitrogen atom, an oxygen atom, or a hetero atom It is a C3-C30 aromatic heterocyclic ring containing any of sulfur atoms, and specifically, a pyridine ring, a pyrimidine ring, a pyrazine ring, a triazine ring, an imidazole ring, an oxazole ring, a thiazole ring, a benzothiazole ring And benzoxazole ring, benzimidazole ring, quinoline ring, isoquinoline ring, quinoxaline ring, quinazoline ring, naphthyridine ring, phenanthridine ring, carbazole ring, dibenzofuran ring and dibenzothiophene ring, preferably pyridine ring and pyrimidine ring , Triazine ring, carbazole ring, dibenzofuran ring, dibe It is a Zochiofen ring.
When any of Ar ²⁰¹ , Ar ²⁰² and Ar ^{203 is} a carbazole ring which may have a substituent, the N-position of the carbazole ring may have a substituent or be bound to an adjacent structure preferable.

When Ar ²⁰² is an aliphatic hydrocarbon structure which may have a substituent, it is an aliphatic hydrocarbon structure having a linear, branched or cyclic structure, preferably having 1 to 24 carbon atoms More preferably, the carbon number is 1 or more and 12 or less, and more preferably 1 or more and 8 or less.

(I1, i2, i3, i4, k1, k2)
i1 and i2 each independently represent an integer of 0 to 12, preferably 1 to 12, more preferably 1 to 8, and more preferably 1 to 6. By being in this range, solubility improvement and charge transportability improvement can be expected.
i3 is preferably an integer of 0 to 5, more preferably 0 to 2, more preferably 0 or 1.
i4 is preferably an integer of 0 to 2, more preferably 0 or 1.
k1 and k2 each independently represent preferably an integer of 0 to 3, more preferably 1 to 3, more preferably 1 or 2, and particularly preferably 1.

(Preferred Substituents of Ar ²⁰¹ , Ar ²⁰² , Ar ²⁰³ )
The substituent which Ar ²⁰¹ , Ar ²⁰² and Ar ²⁰³ may have is optionally selected, but is preferably one or more substituents selected from the above-mentioned Substituent Group S, and preferred groups are also the above-mentioned substituents. As in the group S, more preferably unsubstituted (hydrogen atom), alkyl group or aryl group, particularly preferably unsubstituted (hydrogen atom) or alkyl group, and most preferably unsubstituted (hydrogen atom) ).

(Preferred Embodiment of the Compound Represented by Formula (201))
The compound represented by the formula (201) is preferably a compound satisfying any one or more of the following (I) to (IV).
(I) Phenylene Linkage The structure represented by the formula (202) is a structure having a group in which benzene rings are linked, that is, a benzene ring structure, i1 is 1 to 6, and at least one of the benzene rings is an ortho position or a meta It is preferable that they are bonded to adjacent structures at one position.
Such a structure is expected to improve the solubility and the charge transportability.

(II) (phenylene) -aralkyl (alkyl)
A structure having an aromatic hydrocarbon group or an aromatic heterocyclic group in which an alkyl group or an aralkyl group is bonded to ring A1 or ring A2, ie, Ar ²⁰¹ is an aromatic hydrocarbon structure or aromatic heterocyclic structure, i1 is 1 、 6, Ar ²⁰² is an aliphatic hydrocarbon structure, i2 is 1 to 12, preferably 3 to 8, Ar ²⁰³ is a benzene ring structure, i3 is 0 or 1, preferably Ar ²⁰¹ is the aromatic carbon It is a hydrogen structure, more preferably a structure in which 1 to 5 benzene rings are linked, and more preferably one benzene ring.
Such a structure is expected to improve the solubility and the charge transportability.

(III) Dendron A structure in which a dendron is bonded to ring A1 or ring A2. For example, Ar ²⁰¹ , Ar ²⁰² is a benzene ring structure, Ar ²⁰³ is a biphenyl or terphenyl structure, i1 and i2 are 1 to 6, i3 is 2, j is two.
Such a structure is expected to improve the solubility and the charge transportability.

(IV) B ²⁰¹ -L ²⁰⁰ -B ²⁰²
The structure represented by B ²⁰¹ -L ²⁰⁰ -B ²⁰² is preferably a structure represented by the following formula (203) or the following formula (204).

In formula (203), R ²¹¹ , R ²¹² and R ²¹³ each independently represent a substituent.
In formula (204), ring B3 represents a nitrogen atom-containing aromatic heterocyclic structure which may have a substituent. Ring B3 is preferably a pyridine ring.

(Preferred phosphorescence material)
The phosphorescent material represented by the formula (201) is not particularly limited, but the following may be mentioned as preferable ones.

In addition, a phosphorescent material represented by the following formula (205) is also preferable.

[In Formula (205), M ² represents a metal, and T represents a carbon atom or a nitrogen atom. R ⁹² to R ⁹⁵ each independently represent a substituent. However, when T is a nitrogen atom, R ⁹⁴ and R ⁹⁵ do not exist. ]

In the formula (205), specific examples of M ² include metals selected from Groups 7 to 11 of the periodic table. Among them, preferred is ruthenium, rhodium, palladium, silver, rhenium, osmium, iridium, platinum or gold, and particularly preferred is a divalent metal such as platinum or palladium.

In formula (205), R ⁹² and R ⁹³ each independently represent a hydrogen atom, a halogen atom, an alkyl group, an aralkyl group, an alkenyl group, a cyano group, an amino group, an acyl group, an alkoxycarbonyl group, a carboxyl group, It represents an alkoxy group, an alkylamino group, an aralkylamino group, a haloalkyl group, a hydroxyl group, an aryloxy group, an aromatic hydrocarbon group or an aromatic heterocyclic group.

Furthermore, when T is a carbon atom, R ⁹⁴ and R ⁹⁵ each independently represent a substituent represented by the same example as R ⁹² and R ⁹³ . Also, when T is a nitrogen atom, there is no R ⁹⁴ or R ⁹⁵ directly bonded to T. Further, R ⁹² to R ⁹⁵ may further have a substituent. As a substituent, it can be set as the above-mentioned substituent. Furthermore, any two or more of R ⁹² to R ⁹⁵ may be linked to each other to form a ring.

(Molecular weight)
The molecular weight of the phosphorescent material is preferably 5000 or less, more preferably 4000 or less, particularly preferably 3000 or less. In addition, the molecular weight of the phosphorescent material is usually 800 or more, preferably 1000 or more, more preferably 1200 or more. It is thought that by being in this molecular weight range, the phosphorescent light emitting materials do not aggregate and are uniformly mixed with the charge transporting material, and a light emitting layer having high light emission efficiency can be obtained.
The molecular weight of the phosphorescent light emitting material is high in Tg, melting point, decomposition temperature, etc., and is excellent in heat resistance of the phosphorescent light emitting material and the formed light emitting layer, and film quality caused by gas generation, recrystallization and molecular migration, etc. In the point which it is hard to happen that the fall of, the rise of the impurity concentration accompanying the thermal decomposition of material, etc. occur easily, it is preferable that it is large. On the other hand, the molecular weight of the phosphorescent material is preferably small in terms of easy purification of the organic compound.

<Charge transport material>
The charge transport material of the light emitting layer is a material having a skeleton excellent in charge transportability, and is preferably selected from an electron transport material, a hole transport material, and an ambipolar material capable of transporting both electrons and holes. .

Specific examples of the skeleton having excellent charge transportability include aromatic structures, aromatic amine structures, triarylamine structures, dibenzofuran structures, naphthalene structures, phenanthrene structures, phthalocyanine structures, porphyrin structures, thiophene structures, benzylphenyl structures, The fluorene structure, quinacridone structure, triphenylene structure, carbazole structure, pyrene structure, anthracene structure, phenanthroline structure, quinoline structure, pyridine structure, pyrimidine structure, triazine structure, oxadiazole structure, imidazole structure and the like can be mentioned.

As the electron transporting material, a compound having a pyridine structure, a pyrimidine structure, or a triazine structure is more preferable, and a compound having a pyrimidine structure or a triazine structure, from the viewpoint of being a material having excellent electron transporting property and a relatively stable structure. Is more preferred.

The hole transportable material is a compound having a structure excellent in hole transportability, and among the central skeleton excellent in charge transportability, a carbazole structure, a dibenzofuran structure, a triarylamine structure, a naphthalene structure, a phenanthrene structure or A pyrene structure is preferable as a structure excellent in hole transportability, and a carbazole structure, a dibenzofuran structure or a triarylamine structure is more preferable.

The charge transport material used in the light emitting layer preferably has a fused ring structure having three or more rings, and is a compound having two or more fused ring structures having three or more rings or a compound having at least one fused ring having five or more rings. Is more preferred. With these compounds, the rigidity of the molecule is increased, and the effect of suppressing the degree of molecular motion in response to heat is easily obtained. Furthermore, a fused ring having three or more rings and a fused ring having five or more rings are preferably aromatic hydrocarbon rings or aromatic heterocycles in view of charge transportability and durability of the material.

Specific examples of the fused ring structure having three or more rings include anthracene structure, phenanthrene structure, pyrene structure, chrysene structure, naphthacene structure, triphenylene structure, fluorene structure, benzofluorene structure, indenofluorene structure, indolofluorene structure, Examples thereof include a carbazole structure, an indenocarbazole structure, an indolocarbazole structure, a dibenzofuran structure, and a dibenzothiophene structure. From the viewpoint of charge transportability and solubility, at least one selected from the group consisting of phenanthrene structure, fluorene structure, indenofluorene structure, carbazole structure, indenocarbazole structure, indolocarbazole structure, dibenzofuran structure and dibenzothiophene structure is Preferably, a carbazole structure or an indolocarbazole structure is more preferable from the viewpoint of durability against charge.

In the present invention, at least one of the charge transport materials of the light emitting layer is preferably a material having a pyrimidine skeleton or a triazine skeleton from the viewpoint of durability of the organic electroluminescent element to electric charge.

The charge transport material of the light emitting layer is preferably a polymer material from the viewpoint of excellent flexibility. The light emitting layer formed using the material which is excellent in flexibility is preferable as a light emitting layer of the organic electroluminescent element formed on the flexible substrate. When the charge transport material contained in the light emitting layer is a polymer material, the molecular weight is preferably 5,000 or more and 1,000,000 or less, more preferably 10,000 or more and 500,000 or less, further preferably 10, It is more than 000 and less than 100,000.

In addition, the charge transport material of the light emitting layer is easy to synthesize and purify, to design electron transport performance and hole transport performance, and to adjust viscosity when dissolved in a solvent. It is preferable that it is a low molecule. When the charge transport material contained in the light emitting layer is a low molecular weight material, the molecular weight is preferably 5,000 or less, more preferably 4,000 or less, particularly preferably 3,000 or less, and most preferably 2 Or less, usually 300 or more, preferably 350 or more, and more preferably 400 or more.

<Blue fluorescent light emitting material>
The blue fluorescent material is not particularly limited, but a compound represented by the following formula (211) is preferable.

In the above formula (211), Ar ²⁴¹ represents an aromatic hydrocarbon fused ring structure which may have a substituent, Ar ²⁴² and Ar ²⁴³ each independently represent an alkyl group which may have a substituent, It represents an aromatic hydrocarbon group or a group to which these are bonded. n41 is an integer of 1 to 4;

Ar ²⁴¹ preferably represents an aromatic hydrocarbon fused ring structure having a carbon number of 10 to 30, and specific ring structures such as naphthalene, acenaphthene, fluorene, anthracene, phenanthrene, fluoranthene, pyrene, tetracene, chrysene, perylene and the like It can be mentioned.
Ar ²⁴¹ is more preferably an aromatic hydrocarbon fused ring structure having 12 to 20 carbon atoms, and specific ring structures include acenaphthene, fluorene, anthracene, phenanthrene, fluoranthene, pyrene, tetracene, chrysene, perylene .
Ar ²⁴¹ is more preferably an aromatic hydrocarbon fused ring structure having 16 to 18 carbon atoms, and specific ring structures include fluoranthene, pyrene and chrysene.

N41 is 1 to 4, preferably 1 to 3, more preferably 1 to 2, and most preferably 2.

The alkyl group of Ar ²⁴² and Ar ²⁴³ is preferably an alkyl group having 1 to 12 carbon atoms, more preferably an alkyl group having 1 to 6 carbon atoms.
The aromatic hydrocarbon group of Ar ²⁴² and Ar ²⁴³ is preferably an aromatic hydrocarbon group having 6 to 30 carbon atoms, more preferably an aromatic hydrocarbon group having 6 to 24 carbon atoms, and most preferably a phenyl group. And a naphthyl group.

The substituent which Ar ²⁴¹ , Ar ²⁴² and Ar ²⁴³ may have is preferably a group selected from Substituent Group S, more preferably a hydrocarbon group contained in Substituent Group S, and still more preferably Is a hydrocarbon group among groups preferable as Substituent Group S.

The charge transporting material to be used together with the blue fluorescent light emitting material is not particularly limited, but those represented by the following formula (212) are preferable.

In the above formula (212), R ²⁵¹ and R ²⁵² each independently represent a structure represented by formula (213), R ²⁵³ represents a substituent, and when there are a plurality of R ^{253 's} , they are identical or different. N43 may be an integer of 0-8.

In the above formula (213), * represents a bond with the anthracene ring of formula (212), and Ar ²⁵⁴ and Ar ²⁵⁵ each independently represent an aromatic hydrocarbon structure which may have a substituent, or a substituent And each of Ar ²⁵⁴ and Ar ²⁵⁵ may be the same or different, and n 44 is an integer of 1 to 5, and n 45 is 0. It is an integer of ~ 5.

Ar ²⁵⁴ is preferably an aromatic hydrocarbon structure which may have a substituent, which is a monocyclic or fused ring having 6 to 30 carbon atoms, and more preferably, may have a substituent And an aromatic hydrocarbon structure which is a monocyclic or fused ring having 6 to 12 carbon atoms.

Ar ²⁵⁵ is preferably an optionally substituted aromatic hydrocarbon structure which is a monocyclic or fused ring having 6 to 30 carbon atoms, or may have a substituent, having 6 carbon atoms An aromatic heterocyclic structure which is a fused ring of -30, and more preferably an aromatic hydrocarbon structure which is a monocyclic or fused ring having 6 to 12 carbon atoms, which may have a substituent, or It is an aromatic heterocyclic ring structure which is a fused ring having 12 carbon atoms which may have a substituent.

n44 is preferably an integer of 1 to 3, more preferably 1 or 2, and
n 45 is preferably an integer of 0 to 3, more preferably 0 to 2.

The substituent that the substituent R ²⁵³ and Ar ²⁵⁴ and Ar ²⁵⁵ may have is preferably a group selected from Substituent Group S, more preferably a hydrocarbon group included in Substituent Group S. And more preferably a hydrocarbon group among groups preferable as Substituent Group S.

The molecular weight of the blue fluorescent light emitting material and the charge transport material is preferably 5,000 or less, more preferably 4,000 or less, particularly preferably 3,000 or less, most preferably 2,000 or less, and usually 300 The above, preferably 350 or more, more preferably 400 or more.

[Preferred embodiment of organic electroluminescent device]
The organic electroluminescent device of the present invention is
In the hole injection layer formed between the anode and the light emitting layer,
Containing the hole transporting compound and the electron accepting ion compound, or
The charge transporting ionic compound which is an ionic compound of a cation of the hole transporting compound and a counter anion of the electron accepting ionic compound,
The light emitting layer is preferably the phosphorescent light emitting layer or the blue fluorescent light emitting layer.
By having such a layer configuration, the hole injection property from the electrode is high and the voltage is lowered to increase the light emission efficiency, particularly when the light emitting layer is the phosphorescence light emitting layer or the blue fluorescence light emitting layer, It is more preferable because it is considered that an element having low voltage, high efficiency and long life can be obtained. Further, the hole transporting compound has a crosslinking group, and the electron accepting ionic compound or the counter anion of the electron accepting ionic compound can crosslink the crosslinking group of the hole transporting compound. By having it, it is expected that the light emission efficiency will be higher because the counter anion of the electron accepting ion compound or the electron accepting ion compound does not diffuse to the light emitting layer by binding to the hole transporting compound. Because of that, it is more desirable.
As such an electron accepting ionic compound, the electron accepting compound AC is more preferable, and the electron accepting compound AC further preferably has the crosslinking group.

[Organic EL Display Device]
The organic EL display device of the present invention is a display device using the above-described organic electroluminescent element of the present invention. The type and structure of the organic EL display device of the present invention are not particularly limited, and the organic EL display device of the present invention can be assembled according to a conventional method using the organic electroluminescent device.
For example, the organic EL display device of the present invention can be obtained by the method described in “Organic EL display” (Am Co., published on August 20, 2004, Shimizu Toki, Chiya Adachi, Hideyuki Murata). It can be formed.

[Organic EL lighting]
The organic EL illumination of the present invention is illumination using the above-mentioned organic electroluminescent device of the present invention. There are no particular restrictions on the type and structure of the organic EL lighting of the present invention, and the organic electroluminescent device of the present invention can be assembled according to a conventional method.

Hereinafter, the present invention will be described in more detail by way of examples. The following examples are presented to explain the present invention in detail, and the present invention is not limited to the following examples as long as the gist of the present invention is not violated.

[Synthesis of Polymer 1]
Polymer 1 was synthesized according to the following reaction formula.

4,4'-Dibromobiphenyl (2.50 g, 0.64 mmol), 2-amino-9,9-dihexylfluorene (3.86 g, 11.1 mmol), compound 1 (0.662 g, 0.91 mmol), tert Sodium butoxy (4.77 g, 49.7 mmol) and toluene (40 g) were charged into a flask, and the system was sufficiently purged with nitrogen and heated to 60 ° C. (solution A).
[4- (N, N-dimethylamino) phenyl] di-tert-butyl in a solution of 6.6 g of toluene in tris (dibenzylideneacetone) dipalladium complex (0.118 g, 0.13 mmol) charged in another flask Phosphine (0.273 g, 1.0 mmol) was added and warmed to 60 ° C. (solution B).
Solution B was added to solution A in a nitrogen stream, and the reaction was heated to reflux for 1.0 hour. It was confirmed that each monomer disappeared, and 2,7-bis (4-bromophenyl) -9,9-dihexylfluorene (2.99 g, 4.63 mmol) was added. After heating to reflux for 1 hour, bromobenzene (3.03 g, 19.3 mmol) was added and heated to reflux for 2 hours. The reaction solution was allowed to cool, 30 ml of toluene was added, and the mixture was added dropwise to ethanol (200 ml) to obtain a crude polymer.

The crude polymer was dissolved in toluene, and acetone was dropped to precipitate. The precipitated polymer was separated, redissolved in toluene, washed with dilute aqueous hydrochloric acid, and reprecipitated with ammonia-containing ethanol. The filtered polymer was purified by column chromatography to obtain polymer 1 (3.5 g). The molecular weight and the degree of dispersion of the resulting polymer 1 were as follows.
Weight average molecular weight (Mw) = 17300
Number average molecular weight (Mn) = 12400
Degree of dispersion (Mw / Mn) = 1.40

[Synthesis of Polymer 2]
Polymer 2 was synthesized according to the following reaction formula.

4,4'-Dibromobiphenyl (2.50 g, 0.64 mmol), 2-amino-9,9-dihexylfluorene (3.86 g, 11.1 mmol), compound 2 (0.364 g, 0.91 mmol), compound 1 (0.331 g, 0.91 mmol), tert-butoxy sodium (4.77 g, 49.7 mmol), toluene (40 g) were charged in a flask, and the interior of the system was fully purged with nitrogen and heated to 60 ° C. (Solution C).
[4- (N, N-dimethylamino) phenyl] di-tert-butyl in a solution of 6.6 g of toluene in tris (dibenzylideneacetone) dipalladium complex (0.118 g, 0.13 mmol) charged in another flask Phosphine (0.273 g, 1.0 mmol) was added and warmed to 60 ° C. (solution D).
Solution D was added to solution C in a nitrogen stream, and the reaction was heated to reflux for 1.0 hour. It was confirmed that each monomer disappeared, and 2,7-bis (4-bromophenyl) -9,9-dihexylfluorene (2.99 g, 4.63 mmol) was added. After heating to reflux for 1 hour, bromobenzene (3.03 g, 19.3 mmol) was added and heated to reflux for 2 hours. The reaction solution was allowed to cool, 30 ml of toluene was added, and the mixture was added dropwise to ethanol (200 ml) to obtain a crude polymer.

The crude polymer was dissolved in toluene, and acetone was dropped to precipitate. The precipitated polymer was separated, redissolved in toluene, washed with dilute aqueous hydrochloric acid, and reprecipitated with ammonia-containing ethanol. The collected polymer was purified by column chromatography to obtain polymer 2 (3.5 g). The molecular weight and dispersion degree of the obtained polymer 2 were as follows.
Weight average molecular weight (Mw) = 16,800
Number average molecular weight (Mn) = 12300
Degree of dispersion (Mw / Mn) = 1.36

<Fabrication of Organic Electroluminescent Device>
Fig. The organic electroluminescent element which has a structure shown to 1b was produced with the following method.

Example 1
A 50 nm thick indium-zinc oxide (IZO) transparent conductive film is deposited on a glass substrate 101 (Geomatech Co., Ltd., sputter deposited product) using ordinary photolithography technology and hydrochloric acid etching. The anode 102 was formed by patterning into a stripe of 2 mm width. The patterned IZO substrate is washed in the following order: ultrasonic cleaning with a surfactant solution, water washing with ultrapure water, ultrasonic washing with ultrapure water, and water washing with ultrapure water, followed by drying with compressed air and finally ultraviolet light Ozone cleaning was performed. This IZO functions as the transparent electrode 102.

Next, it contains an arylamine polymer represented by the following structural formula (P-1), 4-isopropyl-4′-methyldiphenyliodonium tetrakis (pentafluorophenyl) borate represented by the structural formula (A-1) and butyl benzoate A coating solution for forming a hole injection layer was prepared. This coating liquid was formed into a film by spin coating on the anode 102 under the following conditions to obtain a hole injection layer 103 with a film thickness of 40 nm.

Coating solution for forming hole injection layer
Solvent butyl benzoate coating solution concentration P-1 2.0 mass%
A-1 0.4 mass%
<Deposition condition>
Spin coat atmosphere Atmosphere Heating conditions Atmosphere 240 ° C 1 hour

Next, an arylamine polymer having methylstyrene (MeSt) as a crosslinking group and 1,2-dihydrocyclobuta (a) naphthalene (CBN) as a charge transporting compound, which is represented by the following structural formula (P-2) Using the ionic compound which does not have a crosslinking group and which is shown to Structural formula (A-2) as an electron-accepting compound, these were dissolved in phenyl cyclohexane and the coating liquid for hole-transport layer formation was prepared. This coating liquid was formed into a film by spin coating on the hole injection layer 103 under the following conditions, and was heated and crosslinked to form a hole transport layer 104 with a film thickness of 40 nm.

<Coating liquid for forming hole transport layer>
Solvent Phenylcyclohexane Coating solution concentration P-2 3.0 mass%
A-2 0.15 mass%
<Deposition condition>
Spin coating atmosphere Dry nitrogen Heating condition Dry nitrogen 230 ° C 30 minutes

Next, using the organic compound (H-1), the organic compound (H-2), and the organic compound (H-3) shown below as the charge transport material of the light emitting layer, the iridium complexes shown below as the light emitting material Using the compound (D-1), a coating solution for forming a light emitting layer containing an iridium complex compound shown below was prepared. Then, the light emitting layer 105 was obtained with a film thickness of 60 nm by spin coating on the hole transport layer 104 under the conditions shown below.

<Coating solution for forming a light emitting layer>
Solvent Phenylcyclohexane Coating solution concentration H-1 22.5 mass%
H-2 22.5 mass%
H-3 55 mass%
D-1 30% by mass
<Deposition condition>
Spin coating atmosphere Dry nitrogen Heating condition Dry nitrogen 130 ° C 20 minutes

Here, the substrate on which the light emitting layer 105 was formed was transferred into a vacuum deposition apparatus, and a 2: 3 mixture of an organic compound (ET-1) having a structure shown below and Liq was deposited by a vacuum deposition method. The electron transport layer 106 having a thickness of 30 nm was formed on the light emitting layer 105 under the control of 0.8 to 1.0 Å / sec.

Here, the device on which the electron transport layer 106 has been deposited is placed in another deposition apparatus, and a stripe-shaped shadow mask with a width of 2 mm is used as a mask for cathode deposition so that the device intersects the IZO stripes of the anode 102 at right angles. I was in close contact with Next, aluminum was heated by a molybdenum boat as the cathode 107 to form an aluminum layer having a thickness of 80 nm.

Subsequently, in order to prevent the element from being deteriorated due to moisture and the like in the air during storage, sealing treatment was performed by the method described below.
In a nitrogen glove box, a photocurable resin 30Y-437 (manufactured by ThreeBond) is applied with a width of about 1 mm on the outer peripheral portion of a 23 mm × 23 mm size glass plate, and a moisture getter sheet (manufactured by Dinic) at the central portion Installed. On this, the substrate on which the formation of the cathode was completed was pasted so that the vapor-deposited surface faced the desiccant sheet. After that, ultraviolet light was irradiated only to the area where the photocurable resin was applied to cure the resin.
As described above, an organic electroluminescent device having a light emitting area with a size of 2 mm × 2 mm was obtained.

Example 2
In Example 1, (P-2) used in forming the hole transport layer was changed to an arylamine polymer represented by the following structural formula (P-3) and having methylstyrene (MeSt) as a crosslinking group In the same manner as in Example 1 except for FIG. The organic electroluminescent element shown to 1b was produced.

Comparative Example 1
Example 1 Example 1 except that (P-2) used in forming the hole transport layer is changed to an arylamine polymer (P-4) having only CBN as a crosslinking group, which is shown below. In the same manner as in FIG. The organic electroluminescent element shown to 1b was produced.

The evaluation results of the element characteristics of Examples 1 and 2 and Comparative Example 1 are shown in Table 1. As for ΔV (V) shown in Table 1, the voltage (V) was measured when current was caused to flow at a current density of 10 mA / cm ^{2 in} the device, and the difference was based on Comparative Example 1 (0.00 V). I asked for. The fact that ΔV is negative indicates that the voltage is lowered. As shown in Table 1, the devices of Examples 1 and 2 have a lower voltage at constant current than Comparative Example 1. This suggests that the methylstyrene cross-linked portion is less likely to trap charges.

Example 3
In Example 2, (H-1), (H-2), (H-3) and (D-1) used to form the light emitting layer are organic compounds (H-4) shown below, A coating solution for forming a light emitting layer containing the following iridium complex compound is prepared by changing to the organic compound (H-5) and the iridium complex compound (D-2), and the film thickness of the light emitting layer is 80 nm In the same manner as in Example 2, FIG. The organic electroluminescent element shown to 1b was produced.

<Coating solution for forming a light emitting layer>
Solvent Phenylcyclohexane Coating solution concentration H-4 30% by mass
H-5 70 mass%
D-2 20 mass%

Comparative example 2
In Example 3, except that (P-3) used in forming the hole transport layer was changed to (P-4), the process of FIG. The organic electroluminescent element shown to 1b was produced.

The evaluation results of the element characteristics of Example 3 and Comparative Example 2 are shown in Table 2. Similar to Table 1, ΔV (V) shown in Table 2 indicates the difference with Comparative Example 2 as the reference (0.00 V). As shown in Table 2, the device of Example 3 has a lower voltage at constant current than Comparative Example 2. This suggests that the methylstyrene cross-linked portion is less likely to trap charges.

Example 4
In Example 2, except that (A-2) used for forming the hole transport layer was changed to (A-3), the process of FIG. The organic electroluminescent element shown to 1b was produced.

Example 5
In Example 4, except that (P-3) used to form the hole transport layer is changed to (P-2), the process of FIG. The organic electroluminescent element shown to 1b was produced.

Comparative example 3
In Example 4, except that (P-3) used in forming the hole transport layer was changed to (P-4), the process of FIG. The organic electroluminescent element shown to 1b was produced.

The evaluation results of the element characteristics of Examples 4 and 5 and Comparative Example 3 are shown in Table 3. Similar to Table 1, ΔV (V) shown in Table 3 indicates the difference with Comparative Example 3 as the reference (0.00 V). As shown in Table 3, the devices of Examples 4 and 5 have a lower voltage at constant current than Comparative Example 3. This means that when the crosslinking group of the charge transporting compound is methylstyrene and the crosslinking group of the electron accepting compound is the crosslinking group represented by the formula (7), the crosslinked portion is unlikely to be a charge trap. It is a suggestion.

Example 6
In Example 2, the indium-zinc oxide (IZO) transparent conductive film is used to form the hole transport layer to the indium-tin oxide (ITO) transparent conductive film, and (A-2) is shown below. In the same manner as in Example 2, except that benzocyclobutene (BCB) was used as the crosslinking group, the procedure was changed to (A-4). The organic electroluminescent element shown to 1b was produced.

Example 7
[Example 6] Example 6 is carried out except that (P-3) used in forming the hole transport layer is changed to an arylamine polymer (P-5) having stilbene (StB) as a crosslinking group shown below. Similarly to Example 6, FIG. The organic electroluminescent element shown to 1b was produced.

The evaluation results of the element characteristics of Examples 6 and 7 are shown in Table 4. The ΔV (V) shown in Table 4 is a voltage (V) when light is emitted by supplying a current at a current density of 10 mA / cm ^{2 to} the device, and Example 6 is used as a standard (0.00 V). The difference between 6 and Example 7 is obtained. As shown in Table 4, methylstyrene is at a lower voltage for the methylstyrene and stilbene cross-linking groups.

Example 8
In Example 7, except that (A-4) used in forming the hole transport layer was changed to (A-3), the process of FIG. The organic electroluminescent element shown to 1b was produced.

Example 9
As in Example 7, FIG. The organic electroluminescent element shown to 1b was produced.

Comparative example 4
In Example 9, except that (A-4) used in forming the hole transport layer is changed to (A-2), the process of FIG. The organic electroluminescent element shown to 1b was produced.

The luminous efficiency ratio and the driving life ratio of the device prepared as described above were evaluated as follows.
The luminous efficiency ratio was determined as follows.
The current luminous efficiency (cd / A) when light is passed through a current at a current density of 10 mA / cm ² is determined, and the relative value when the current luminous efficiency of the element of Comparative Example 4 is 1 is defined as the luminous efficiency It is a ratio. That is, the current luminous efficiency of Examples 8 and 9 was divided by the current luminous efficiency of Comparative Example 4 to obtain.
The life ratio was determined as follows.
When the device is made to emit light by continuously applying current at a current density of 20 mA / cm ² , the time when the luminance falls to 70% of the initial time is determined as LT70 (hr), and LT70 of Comparative Example 4 is 1 The relative value of was taken as the life ratio. That is, the value obtained by dividing the LT 70 of Examples 8 and 9 by the LT 70 of Comparative Example 4 was taken as the life ratio.
The results are shown in Table 5.
As shown in Table 5, the composition having a crosslinking group in the electron accepting compound had high efficiency and long life.

Example 10
As in Example 6, FIG. The organic electroluminescent element shown to 1b was produced.

Comparative example 5
In Example 10, except that (A-4) used in forming the hole transport layer is changed to (A-2), the process of FIG. The organic electroluminescent element shown to 1b was produced.

The luminous efficiency ratio and the driving life ratio of the device prepared as described above were evaluated in the same manner as in Examples 8 and 9 and Comparative Example 4 described above with Comparative Example 5 as a reference. The results are shown in Table 6.
As shown in Table 6, the composition having a crosslinking group in the electron accepting compound had high efficiency and long life.

Although the invention has been described in detail with particular embodiments, it will be apparent to those skilled in the art that various modifications can be made without departing from the spirit and scope of the invention.
This application is based on Japanese Patent Application No. 2017-182867 filed on September 22, 2017, which is incorporated by reference in its entirety.

100a, 100b, 100c organic electroluminescent device 101 substrate 102 anode 103 hole injection layer 104 hole transport layer 105 light emitting layer 106 electron transport layer 107 cathode 108 hole blocking layer

Claims

A charge transporting compound having a structural unit represented by the following formula (1):
A composition comprising a compound having a structural unit represented by the following formula (5), formula (6) or formula (7).

[In Formula (1), X 1 is a group represented by the following Formula (2). ]

[In the formula (2),
* Represents a binding site to N in formula (1),
Y 1 is a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms, a substituted or unsubstituted aminoarylene group, a chalcogen atom, a carbonyl group, or a substituted or unsubstituted 1 to 20 carbon atoms Indicates an alkylene group.
R 11 represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms, or a substituted or unsubstituted arylamino group.
R 12 represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms or a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms.
The substituent of R 11 and R 12 may combine to form a ring.
k is an integer of 1 or more and 10 or less, and Y 1 when k is 2 or more may be the same or different.
m is 1 or 2 and R 12 when m is 2 may be the same or different.
n is 0 or 1. ]

[In the formula (5),
* Represents a binding site,
E 1 , E 2 and E 3 each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms, a fluorine Represents an atom or a substituted carbonyl group.
However, E 2 and E 3 are not simultaneously hydrogen atoms. ]

[In the formula (6),
* Represents a binding site,
R 31 is a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms , A substituted or unsubstituted alkyloxy group having 1 to 10 carbon atoms, a fluorine atom or a substituted carbonyl group,
j represents an integer of 0 or more and 5 or less, and R 31 when j is 2 or more may be the same or different. ]

[In the formula (7),
* Represents a binding site,
R 41 is a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms , A fluorine atom or a substituted carbonyl group,
y represents an integer of 0 or more and 5 or less, and R 41 when y is 2 or more may be the same or different. ]
The composition according to claim 1, wherein R 12 in the formula (2) is an alkyl group having 1 or more and 20 or less carbon atoms.
The composition according to claim 1 or 2, wherein n in formula (2) is 0.
The composition according to any one of claims 1 to 3, wherein the charge transporting compound contains a structural unit represented by the following formula (3).

[In the formula (3),
Each of Ar 21 and Ar 22 independently represents a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms.
R 21 represents a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms, or a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms.
a is an integer of 1 or more and 5 or less, and when R 21 is 2 or more, Ar 21 may be the same or different.
b is an integer of 0 or more and 5 or less, and R 21 when b is 2 or more may be the same or different. ]
The 5% mass loss start temperature of the compound which has a structural unit represented by said Formula (5), Formula (6), or Formula (7) is 300 degrees C or less, It is described in any one of Claims 1-4. Composition of
The composition according to any one of claims 1 to 5, wherein the polymerization initiation temperature of the compound having a structural unit represented by the formula (5), (6) or (7) is 80 ° C or higher. .
The compound which has a structural unit represented by said Formula (5), Formula (6), or Formula (7) is a compound represented by following formula (4), in any one of Claims 1-6. Composition as described.

[In the formula (4),
Y − represents an anion and Z + represents a cation, and a pair of Y − and Z + represents a compound.
L 1 represents a single bond, a chalcogen atom, a carbonyl group, a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms, or an substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms;
L 1 is bound to Y - or Z + ,
L 2 is represented by the formula (5), the formula (6) or the formula (7).
d and e are each independently an integer of 1 to 5, and when d is 2 or more, L 1 may be the same or different, and when e is 2 or more, L 2 may be the same or different May be
f is an integer of 1 or more and 4 or less, and when f is 2 or more, L 1 , L 2 , d and e in the formula (4) may be the same or different, and when f is 2 or more, e is an integer of 1 or more and 5 or less, and at least one e is 1 or more. ]
The composition according to any one of claims 1 to 7, which is used for a hole injection layer and / or a hole transport layer of an organic electroluminescent device.
9. An organic electroluminescent device comprising a light emitting layer, a hole injection layer and / or a hole transport layer between an anode and a cathode, wherein the hole injection layer and / or the hole transport layer is any one of claims 1 to 8. An organic electroluminescent device which is a layer formed by coating and drying the composition according to any one of the items 1 to 4.
An organic EL display device using the organic electroluminescent device according to claim 9.
The organic electroluminescent illumination using the organic electroluminescent element of Claim 9.
The compound which has a structural unit represented by following formula (5), Formula (6), or Formula (7).

[In the formula (5),
* Represents a binding site,
E 1 , E 2 and E 3 each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms, a fluorine Represents an atom or a substituted carbonyl group.
However, E 2 and E 3 are not simultaneously hydrogen atoms. ]

[In the formula (6),
* Represents a binding site,
R 31 is a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms , A substituted or unsubstituted alkyloxy group having 1 to 10 carbon atoms, a fluorine atom or a substituted carbonyl group,
j represents an integer of 0 or more and 5 or less, and R 31 when j is 2 or more may be the same or different. ]

[In the formula (7),
* Represents a binding site,
R 41 is a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms , A fluorine atom or a substituted carbonyl group,
y represents an integer of 0 or more and 5 or less, and R 41 when y is 2 or more may be the same or different. ]
The charge transportable compound containing the structural unit represented by following formula (10).

Wherein (10), X 1 'is a group represented by the following formula (11). ]

[In the formula (11),
* Represents a binding site to N in formula (10),
Y 1 ′ represents a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms, a chalcogen atom, a carbonyl group, or a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms.
R 11 ′ represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms, or a substituted or unsubstituted arylamino group.
R 12 ′ represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aromatic ring group having 3 to 60 ring atoms.
The substituent of R 11 ′ and R 12 ′ may combine to form a ring.
k 'is an integer of 1 or more and 10 or less, Y 1 ' when k 'is 2 or more may be the same or different, R 12 ' is an aromatic hydrocarbon group, and C = C type When Y 1 ′ directly bonded to a double bond is a benzene ring, k ′ is 2 or more.
m'is 1 or 2, m'is R 12 in case of 2 'may be the same or different.
n 'is 0 or 1. ]