JP2008179790A - Organic compound having crosslinking group, material for organic electroluminescence element, composition for organic electroluminescence element and organic electroluminescence element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic compound which is capable of forming a flat thin film and is excellent in hole-transporting property and storage stability, and an organic electroluminescence element showing a high luminous efficiency and operation stability using the organic compound. <P>SOLUTION: In the organic electroluminescence element, at least one of organic layers contains the organic compound of formula (I) [wherein n is 0, 1 or 2; T<SP>1</SP>and T<SP>2</SP>are each a crosslinking group; G<SP>1</SP>-G<SP>3</SP>are each a bivalent group formed by linking 1-30 groups chosen from a phenylene group and groups of the formulae: -O-, -C(=O)- and -CH<SB>2</SB>-; and A<SP>1</SP>and A<SP>2</SP>are each a bivalent group of formula (I-1) (wherein m is 0 or 1; Ar<SP>1</SP>-Ar<SP>5</SP>are each an aromatic hydrocarbon group or an aromatic heterocyclic group; and A<SP>1</SP>satisfies the relation: Ar<SP>1</SP>≠Ar<SP>2</SP>)]. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an organic compound having a crosslinking group, which can be formed by a wet film formation method, a composition for an organic electroluminescent element containing the organic compound, and a polymer compound obtained by crosslinking the organic compound. And an organic electroluminescent device having an organic layer containing the organic compound, high luminous efficiency, and excellent driving stability.

In recent years, an electroluminescent element (organic electroluminescent element) using an organic thin film has been developed. Examples of the method for forming the organic thin film in the organic electroluminescence device include a vacuum deposition method and a wet film formation method.
Since the vacuum deposition method can be laminated, it has an advantage that the charge injection from the anode and / or the cathode is improved and the exciton light-emitting layer can be easily contained. The wet film formation method does not require a vacuum process, is easy to increase in area, and has an advantage that it is easy to mix a plurality of materials having various functions into one layer (coating liquid). .

  However, since the wet film forming method is difficult to stack, the driving stability is inferior to that of the element by the vacuum vapor deposition method, and the present state is that it has not reached a practical level except for a part. In particular, the layering by the wet film forming method can be performed by stacking two layers by using an organic solvent and an aqueous solvent, but it is difficult to stack three or more layers.

In order to solve such problems in stacking, Patent Document 1 and Non-Patent Document 1 propose compounds having the following crosslinking groups and disclose stacking using an organic solvent.

  However, the above compound has a problem that since the aromatic amine moiety has high symmetry, it is easily crystallized, hardly forms a flat film, and is not easily insolubilized.

Patent Document 2 describes a compound having low symmetry as described below as a compound used for a layer forming the surface of the electrophotographic photosensitive member.

However, in the above compound, since the crosslinking group is directly bonded to the aromatic amine site, the movement of the crosslinking group is limited and it is considered that the compound is difficult to insolubilize.
WO2005-083812 Japanese Patent Laying-Open No. 2005-066301 Applied Physics Letters 2005, 86, 221022.

It is an object of the present invention to provide an organic compound that can be insolubilized under mild conditions and can form a flat thin film because of its excellent amorphous property, has excellent hole transportability, and excellent storage stability. And
Another object of the present invention is to provide an organic electroluminescent device having high luminous efficiency and high driving stability.

  As a result of intensive studies to solve the above problems, the present inventors have found that an organic compound having a crosslinking group having the following specific structure has a high hole transport ability, a high amorphous property, and mild conditions. It was found that it is a compound suitable for the wet film-forming method, which can be insolubilized and has excellent storage stability.

  The present invention has been achieved on the basis of such findings, and the gist thereof is as follows.

〔式（Ｉ）中、ｎは０、１または２を表す。
Ｔ^１およびＴ^２は、各々独立に架橋基を表す。
Ｇ^１〜Ｇ^３は、各々独立に、フェニレン基、−Ｏ−基、−Ｃ（＝Ｏ）−基および−ＣＨ_２−基からなる群から選ばれる基を１〜３０個連結してなる２価の基を表す。尚、フェニレン基および−ＣＨ_２−基は、置換基を有していてもよい。ただし、Ｇ^１およびＧ^２は、各々独立に、少なくとも１個の該−ＣＨ_２−基を含む基である。
Ａ^１、Ａ^２は、各々独立に、下記式（Ｉ−１）で表される２価の基を表す。

（式（Ｉ−１）中、ｍは０または１を表す。
Ａｒ^１〜Ａｒ^５は、各々独立に、置換基を有していてもよい芳香族炭化水素基または置換基を有していてもよい芳香族複素環基を表す。ただし、Ａ^１における式（Ｉ−１）において、Ａｒ^１とＡｒ^２は同一ではない。また、一分子中に複数Ａｒ^１〜Ａｒ^５がそれぞれ存在する場合にはＡｒ^１〜Ａｒ^５は同一であっても異なっていてもよい。）
ｎ＝２のとき、２個のＧ^３およびＡ^２は、それぞれ同一であっても異なっていてもよい。〕 [1] An organic compound represented by the following formula (I).

[In formula (I), n represents 0, 1 or 2.
T ¹ and T ² each independently represent a crosslinking group.
G ^{1 to} G ³ are each independently formed by linking 1 to 30 groups selected from the group consisting of a phenylene group, —O— group, —C (═O) — group, and —CH ₂ — group. Represents a valent group. In addition, the phenylene group and the —CH ₂ — group may have a substituent. However, G ¹ and G ² are each independently a group containing at least one —CH ₂ — group.
A ¹ and A ² each independently represent a divalent group represented by the following formula (I-1).

(In the formula (I-1), m represents 0 or 1.
Ar ^{1 to} Ar ⁵ each independently represents an aromatic hydrocarbon group which may have a substituent or an aromatic heterocyclic group which may have a substituent. However, in the formula (I-1) in ^{A 1,} Ar ¹ and Ar ² are not the same. Further, when a plurality of Ar ^{1 to} Ar ⁵ are present in one molecule, Ar ^{1 to} Ar ⁵ may be the same or different. )
When n = 2, the two G ³ and A ² may be the same or different. ]

[2] The organic compound according to [1], wherein in formula (I), n is 0.

[3] The organic compound according to [1], wherein in the formula (I), n is 1 or 2, and G ³ is an —O— group.

[4] The organic compound according to any one of [1] to [3], wherein in the formula (I-1), m is 0.

（式中、Ｒ^１〜Ｒ^５は、各々独立に、水素原子またはアルキル基を表す。
Ａｒ^１１は置換基を有していてもよい芳香族炭化水素基または置換基を有していてもよい芳香族複素環基を表す。） [5] The organic material according to any one of [1] to [4], wherein in formula (I), T ¹ and T ² are each independently a crosslinking group selected from the following crosslinking group group T. Compound.
<Crosslinking group T>

(In formula, R < ¹ > -R < ⁵ > represents a hydrogen atom or an alkyl group each independently.
Ar ¹¹ represents an aromatic hydrocarbon group which may have a substituent or an aromatic heterocyclic group which may have a substituent. )

[6] An organic electroluminescent element material comprising the organic compound according to any one of [1] to [5].

[7] A composition for an organic electroluminescence device comprising the organic compound according to any one of [1] to [5].

[8] A polymer compound obtained by polymerizing the organic compound according to any one of [1] to [5].

[9] In an organic electroluminescence device having an anode, a cathode, and one or more organic layers sandwiched between the anode and the cathode on a substrate, at least one of the organic layers is [1] Thru | or the organic electroluminescent element containing the organic compound in any one of [5], and / or the high molecular compound in [8].

[10] The organic electroluminescent element according to [9], wherein the layer containing the organic compound and / or polymer compound is a hole transport layer.

[11] The organic electroluminescence device according to [10], wherein a light emitting layer is provided on the hole transport layer.

[12] The organic layer has a hole injection layer, a hole transport layer, and a light emitting layer, and all of the hole injection layer, the hole transport layer, and the light emitting layer are formed by a wet film forming method. Thru | or the organic electroluminescent element in any one of [11].

  The organic compound of the present invention has high hole transport ability and high amorphousness, can be insolubilized under mild conditions, and is excellent in storage stability. Moreover, this organic compound is suitable for the wet film-forming method, and it becomes possible to form the organic layer of an organic electroluminescent element by this wet film-forming method using this organic compound.

Moreover, the organic electroluminescent element formed by the wet film-forming method using the composition for organic electroluminescent elements containing this organic compound can be enlarged.
Moreover, it is also possible to form an organic thin film insoluble in an organic solvent by using the composition for an organic electroluminescent element containing the organic compound, and the organic electroluminescent element can be easily laminated by a wet film forming method. .

  According to such an organic electroluminescent element containing the organic compound of the present invention, it becomes possible to emit light with high efficiency, and the stability of the element, particularly the driving stability is improved.

  The organic compound of the present invention has a hole injection material, a hole transport material, a light emitting material, a host material, and an electron injection according to the layer structure of the device because of its excellent film forming property, charge transport property, light emitting property and heat resistance. It can also be applied as a material, an electron transport material, and the like.

The organic electroluminescent element containing the organic compound of the present invention is a light source (for example, a copier) utilizing characteristics of a flat panel display (for example, for OA computers or wall-mounted televisions), an in-vehicle display element, a mobile phone display or a surface light emitter. The light source, the back light source of liquid crystal displays and instruments), display panels, and sign lamps can be considered, and its technical value is great.
In addition, since the organic compound of the present invention has excellent redox stability, it is useful not only for organic electroluminescent devices but also for electrophotographic photoreceptors.

  Hereinafter, embodiments of the organic compound, organic electroluminescent element material, composition for organic electroluminescent element, polymer compound, and organic electroluminescent element of the present invention will be described in detail. It is an example (representative example) of the embodiment of the present invention, and the present invention is not specified by these contents unless it exceeds the gist.

〔式（Ｉ）中、ｎは０、１または２を表す。
Ｔ^１およびＴ^２は、各々独立に架橋基を表す。
Ｇ^１〜Ｇ^３は、各々独立に、フェニレン基、−Ｏ−基、−Ｃ（＝Ｏ）−基および−ＣＨ_２−基からなる群から選ばれる基を１〜３０個連結してなる２価の基を表す。尚、フェニレン基および−ＣＨ_２−基は、置換基を有していてもよい。ただし、Ｇ^１およびＧ^２は、各々独立に、少なくとも１個の該−ＣＨ_２−基を含む基である。
Ａ^１、Ａ^２は、各々独立に、下記式（Ｉ−１）で表される２価の基を表す。

（式（Ｉ−１）中、ｍは０または１を表す。
Ａｒ^１〜Ａｒ^５は、各々独立に、置換基を有していてもよい芳香族炭化水素基または置換基を有していてもよい芳香族複素環基を表す。ただし、Ａ^１における式（Ｉ−１）において、Ａｒ^１とＡｒ^２は同一ではない。また、一分子中に複数Ａｒ^１〜Ａｒ^５がそれぞれ存在する場合にはＡｒ^１〜Ａｒ^５は同一であっても異なっていてもよい。）
ｎ＝２のとき、２個のＧ^３およびＡ^２は、それぞれ同一であっても異なっていてもよい。〕 [Organic compounds]
The organic compound of the present invention is represented by the following formula (I).

[In formula (I), n represents 0, 1 or 2.
T ¹ and T ² each independently represent a crosslinking group.
G ^{1 to} G ³ are each independently formed by linking 1 to 30 groups selected from the group consisting of a phenylene group, —O— group, —C (═O) — group, and —CH ₂ — group. Represents a valent group. In addition, the phenylene group and the —CH ₂ — group may have a substituent. However, G ¹ and G ² are each independently a group containing at least one —CH ₂ — group.
A ¹ and A ² each independently represent a divalent group represented by the following formula (I-1).

(In the formula (I-1), m represents 0 or 1.
Ar ^{1 to} Ar ⁵ each independently represents an aromatic hydrocarbon group which may have a substituent or an aromatic heterocyclic group which may have a substituent. However, in the formula (I-1) in ^{A 1,} Ar ¹ and Ar ² are not the same. Further, when a plurality of Ar ^{1 to} Ar ⁵ are present in one molecule, Ar ^{1 to} Ar ⁵ may be the same or different. )
When n = 2, the two G ³ and A ² may be the same or different. ]

[1] Structural features The organic compound of the present invention has an asymmetric aromatic amine moiety, and has a spacer group between the aromatic amine moiety and the crosslinking group. It is possible to make a film having a transporting property, a high amorphous property, and a film formed by a wet film formation method insoluble in an organic solvent under mild conditions.

[2] Molecular Weight Range The molecular weight of the organic compound of the present invention is usually 5000 or less, preferably 2000 or less, and usually 400 or more, preferably 500 or more. If the molecular weight exceeds this upper limit, purification may become difficult due to the high molecular weight of impurities, and if the molecular weight falls below this lower limit, the glass transition temperature, melting point, vaporization temperature, etc. will decrease. There is a risk that the properties are significantly impaired.

[3] n
N in the above formula (I) represents 0, 1 or 2.
It is preferable that n = 0 because the organic compound is easy to move, the crosslinking reaction is promoted, and it is easily insolubilized.
It is preferable that n = 1 or 2 because the hole transport property is further improved.

[4] T ¹ , T ²
T ¹ and T ² in the above formula (I) each independently represent a crosslinking group.
T ¹ and T ² are not particularly limited as long as they can form a bond with each other by electromagnetic energy such as heat or light, but a group containing an unsaturated double bond, cyclic ether, benzocyclobutane, or the like is preferable.

  In particular, the cross-linking group is preferably a group selected from the following cross-linking group group T because it is easily insolubilized.

（式中、Ｒ^１〜Ｒ^５は、各々独立に、水素原子又はアルキル基を表す。
Ａｒ^１１は置換基を有してもよい芳香族炭化水素基または置換基を有してもよい芳香族複素環基を表す。） <Crosslinking group T>

(In formula, R < ¹ > -R < ⁵ > represents a hydrogen atom or an alkyl group each independently.
Ar ¹¹ represents an aromatic hydrocarbon group which may have a substituent or an aromatic heterocyclic group which may have a substituent. )

The alkyl group of R ^{1 to} R ⁵ is preferably an alkyl group having 1 to 20 carbon atoms, more preferably an alkyl group having 1 to 10 carbon atoms, and particularly preferably an alkyl group having 1 to 3 carbon atoms.
The aromatic hydrocarbon group and the aromatic heterocyclic group of Ar ¹¹ are the same as the specific examples in the case where Ar ^{1 to} Ar ⁵ described later are an aromatic hydrocarbon group or an aromatic heterocyclic group. Moreover, as the substituent, the group as described in the specific example of the substituent of Ar < ¹ > -Ar < ⁵ > mentioned later is mentioned.

  In particular, it is preferable that the cross-linking group is a group selected from the following cross-linking group group T ′ because of excellent electrochemical durability.

<Crosslinking group T '>

[5] G ^{1 to} G ³
G ^{1 to} G ³ in the above formula (I) are each independently a group selected from the group consisting of a phenylene group, a —O— group, a —C (═O) — group, and a —CH ₂ — group. Represents a divalent group formed by linking them individually. In addition, the phenylene group and the —CH ₂ — group may have a substituent. However, G ¹ and G ² are each independently a group containing at least one —CH ₂ — group.
Specific examples of the substituent that the phenylene group and the —CH ₂ — group may have include the following specific examples of the substituent of Ar ^{1 to} Ar ⁵ , and linear or branched carbon atoms of 1 to 20 Are preferred.

G ^{1, G 2} are that promotes insolubilization, from the viewpoint of excellent electrochemical stability, -CH ₂ -. 2 to the group - divalent group formed by a group linked 2 to 15, -CH ₂ A divalent group formed by connecting 12 and 1 to 3 non-continuous —O— groups is preferable. In particular, the group connected to the aromatic amine moiety (A ¹ , A ² ) is preferably an —O— group from the viewpoint of excellent electrochemical stability and hole transportability.

Further, since the easily ^{insolubilized,} G 1, ^{G 2} is, -O- group, -C (= O) - a group selected from the group - (which may have a substituent) group or -CH ₂ It is preferable that it is a bivalent group formed by connecting 4 to 10 in any order.

When G ¹ or G ² (which may have a substituent) —CH ₂ — group does not exist, or G ¹ or G ² itself does not exist, the movement of the crosslinking group is limited, and the crosslinking reaction Difficult to proceed and difficult to insolubilize.
When G ¹ or G ² is too long, G ² may be solvated and dissolved in an organic solvent even after the crosslinking reaction has proceeded.

G ³ may have an —O— group or a substituent, —O— (CH ₂ ) _r —O— group or a substituent, from the viewpoint of excellent electrochemical stability— CH _{2) r} - group is preferably (r is an integer of 2-6). As a substituent of the —O— (CH ₂ ) _r —O— group or — (CH ₂ ) _r — group, a linear or branched alkyl group having 1 to 20 carbon atoms is preferable.
G ³ is particularly preferably an —O— group from the viewpoint of further improving hole transport ability and excellent heat resistance.

When r = 2, the two G ^{3 s} may be the same or different from each other, but are preferably the same because they are easy to manufacture.

[6] A ¹ , A ²
A ¹ and A ² in the above formula (I) each independently represent a divalent group (aromatic amine moiety) represented by the following formula (I-1).

（式（Ｉ−１）中、ｍは０または１を表す。
Ａｒ^１〜Ａｒ^５は、各々独立に、置換基を有していてもよい芳香族炭化水素基または置換基を有していてもよい芳香族複素環基を表す。ただし、Ａ^１における式（Ｉ−１）において、Ａｒ^１とＡｒ^２は同一ではない。また、一分子中に複数Ａｒ^１〜Ａｒ^５がそれぞれ存在する場合にはＡｒ^１〜Ａｒ^５は同一であっても異なっていてもよい。）

(In the formula (I-1), m represents 0 or 1.
Ar ^{1 to} Ar ⁵ each independently represents an aromatic hydrocarbon group which may have a substituent or an aromatic heterocyclic group which may have a substituent. However, in the formula (I-1) in ^{A 1,} Ar ¹ and Ar ² are not the same. Further, when a plurality of Ar ^{1 to} Ar ⁵ are present in one molecule, Ar ^{1 to} Ar ⁵ may be the same or different. )

In formula (I-1), when n = 1, A ² may be the same as or different from A ¹ . A ² is preferably different from A ¹ because the symmetry is further reduced and an amorphous and flat thin film is obtained. A ² is preferably the same as A ¹ because the production is easy and the hole transport ability is further improved.
When n = 2, the two A ² may be the same or different from each other. In view of easy production, A ² bonded to G ² is preferably the same as A ¹ .

In A ¹ , Ar ¹ and Ar ^{2 in the} formula (I-1) are not the same.
Here, the Ar ¹ and Ar ² are not the same, instead of Ar ¹ aromatic between and Ar ² hydrocarbon group or an aromatic heterocyclic group means only differ, Ar ¹ and Ar ² Even when the aromatic hydrocarbon groups or aromatic heterocyclic groups of the above are the same or have different substituents, or even when the substituents are the same, the substitution positions thereof are different. Ar ¹ and Ar ² are defined not to be the same when the position of the bond to the substituent is different. That is, when Ar ¹ and Ar ² have the same aromatic hydrocarbon group or aromatic heterocyclic group, and the same substituent is substituted, for example, substitution of the substituent of Ar ¹ The position is para to the substitution position with the nitrogen atom (N—Ar ³ ) in formula (I-1), and the substitution position of the substituent of Ar ² is the nitrogen atom (N—Ar ³ or N—Ar ^4). Ar ¹ and Ar ² are not the same if they are in the meta position or the ortho position with respect to the substitution position. Thus, for example, in formulas (I) and (I-1), n = 0 and m = 0, and the organic compound of the present invention is T ¹ -G ¹ -Ar ¹ -N (—Ar ³ ) -Ar ² —. G ² -T ²
In the case where Ar ¹ and Ar ² are both phenylene groups, the —G ¹ -T ¹ group substituted for Ar ¹ is in the para position relative to —N (—Ar ³ ), and Ar 1 Ar ¹ and Ar ² are different if the —G ² -T ² group substituted for ² is a meta position with respect to — (N—Ar ³ ).

In A ^1, by the Ar ¹ and Ar ² are not identical, symmetry lowers the organic compound of the present invention, so that a flat thin film in the amorphous is obtained.

Ar ¹ and Ar ² in the A ² may be the same or different but, Ar ¹ and Ar ² in the ^{A 2} are not identical as in the ^{A 1} is, symmetry is further reduced, non A crystalline and flat thin film can be obtained, which is preferable.

In Formula (I-1), Ar ^{1 to} Ar ⁵ each independently represents an aromatic hydrocarbon group that may have a substituent or an aromatic heterocyclic group that may have a substituent. .

Examples of the aromatic hydrocarbon group optionally having a substituent of Ar ^{1 to} Ar ⁵ include a benzene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, a perylene ring, a tetracene ring, a pyrene ring, a benzpyrene ring, and a chrysene ring. , Monovalent or divalent groups derived from a 5- or 6-membered monocyclic ring or a 2-5 condensed ring, such as a triphenylene ring or a fluoranthene ring.

  Examples of the aromatic heterocyclic group which may have a substituent include a furan ring, a benzofuran ring, a thiophene ring, a benzothiophene ring, a pyrrole ring, a pyrazole ring, an imidazole ring, an oxadiazole ring, an indole ring, and a carbazole ring. , Pyrroloimidazole ring, pyrrolopyrazole ring, pyrrolopyrrole ring, thienopyrrole ring, thienothiophene ring, furopyrrole ring, furofuran ring, thienofuran ring, benzoisoxazole ring, benzoisothiazole ring, benzimidazole ring, pyridine ring, pyrazine ring, pyridazine Monovalent ring derived from a 5- or 6-membered monocyclic ring or a 2-4 condensed ring such as a ring, a pyrimidine ring, a triazine ring, a quinoline ring, an isoquinoline ring, a sinoline ring, a quinoxaline ring, a benzimidazole ring, a perimidine ring or a quinazoline ring Or a divalent group It is.

From the viewpoint of electrochemical stability, Ar ^{1 to} Ar ⁵ are each a monovalent or divalent group derived from a ring selected from the group consisting of a benzene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, a thiophene ring, and a pyridine ring, And the bivalent group which connected the 1 type (s) or 2 or more types of ring chosen from the said group by the direct bond is preferable, and a phenylene group, a biphenylene group, a terphenylene group, and a naphthylene group are still more preferable. In particular, a phenylene group which may have a substituent or a group in which a plurality of phenylene groups which may have a substituent are connected (for example, biphenylene group, terphenylene group, etc.), that is, A phenylene group represented by the formula (IV), a divalent group in which phenylene groups are linked by a direct bond, or a monovalent group corresponding to the divalent group is particularly preferable.

（式（IV）中、ｐは自然数を表し、１〜３が好ましい。式（II）中のベンゼン環は任意の置換基を有していてもよいが、置換基を有していないことが好ましい。〕

(In formula (IV), p represents a natural number and is preferably 1 to 3. The benzene ring in formula (II) may have an arbitrary substituent, but may not have a substituent. preferable.〕

Examples of the substituent that the aromatic hydrocarbon group or aromatic heterocyclic group of Ar ^{1 to} Ar ⁵ may have include the following.

<Specific Examples of Substituents for Ar ^{1 to} Ar ⁵ >
An alkyl group which may have a substituent (preferably a linear or branched alkyl group having 1 to 8 carbon atoms, such as methyl, ethyl, n-propyl, 2-propyl, n-butyl, isobutyl, tert, -A butyl group etc. are mentioned.)
An alkenyl group which may have a substituent (preferably an alkenyl group having 2 to 9 carbon atoms, such as vinyl, allyl, 1-butenyl group, etc.).
An alkynyl group which may have a substituent (preferably an alkynyl group having 2 to 9 carbon atoms, such as ethynyl and propargyl groups).
An aralkyl group which may have a substituent (preferably an aralkyl group having 7 to 15 carbon atoms, such as a benzyl group).
An alkoxy group which may have a substituent (preferably an alkoxy group having 1 to 8 carbon atoms which may have a substituent, such as methoxy, ethoxy and butoxy groups).
An aryloxy group which may have a substituent (preferably an aromatic hydrocarbon group having 6 to 12 carbon atoms, such as phenyloxy, 1-naphthyloxy, 2-naphthyloxy group and the like. .)
A heteroaryloxy group which may have a substituent (preferably has a 5- or 6-membered aromatic heterocyclic group, and examples thereof include a pyridyloxy and thienyloxy group).
An acyl group which may have a substituent (preferably an acyl group having 2 to 10 carbon atoms which may have a substituent, such as formyl, acetyl and benzoyl groups).
An alkoxycarbonyl group which may have a substituent (preferably an alkoxycarbonyl group having 2 to 10 carbon atoms which may have a substituent, such as methoxycarbonyl and ethoxycarbonyl groups).
An aryloxycarbonyl group which may have a substituent (preferably an aryloxycarbonyl group having 7 to 13 carbon atoms which may have a substituent, such as a phenoxycarbonyl group).
An alkylcarbonyloxy group which may have a substituent (preferably an alkylcarbonyloxy group having 2 to 10 carbon atoms which may have a substituent, such as an acetoxy group).
Halogen atoms (especially fluorine or chlorine atoms),
Carboxy group Cyano group Hydroxyl group Mercapto group Alkylthio group which may have a substituent (preferably an alkylthio group having 1 to 8 carbon atoms, such as methylthio group and ethylthio group).
An arylthio group which may have a substituent (preferably an arylthio group having 6 to 12 carbon atoms, such as a phenylthio group and a 1-naphthylthio group).
A sulfonyl group which may have a substituent (for example, a mesyl group, a tosyl group, etc.).
A silyl group which may have a substituent (for example, a trimethylsilyl group, a triphenylsilyl group, etc.).
An optionally substituted boryl group (eg, a dimesitylboryl group).
A phosphino group which may have a substituent (for example, a diphenylphosphino group).
An aromatic hydrocarbon group which may have a substituent (for example, benzene ring, naphthalene ring, anthracene ring, phenanthrene ring, perylene ring, tetracene ring, pyrene ring, benzpyrene ring, chrysene ring, triphenylene ring, fluoranthene ring, etc. And monovalent groups derived from 5- or 6-membered monocyclic rings or 2 to 5 condensed rings.)
An aromatic heterocyclic group which may have a substituent (for example, furan ring, benzofuran ring, thiophene ring, benzothiophene ring, pyrrole ring, pyrazole ring, imidazole ring, oxadiazole ring, indole ring, carbazole ring, pyrrolo) Imidazole ring, pyrrolopyrazole ring, pyrrolopyrrole ring, thienopyrrole ring, thienothiophene ring, furopyrrole ring, furofuran ring, thienofuran ring, benzisoxazole ring, benzoisothiazole ring, benzimidazole ring, pyridine ring, pyrazine ring, pyridazine ring, A monovalent group derived from a 5- or 6-membered monocyclic ring or a 2-4 condensed ring such as a pyrimidine ring, a triazine ring, a quinoline ring, an isoquinoline ring, a sinoline ring, a quinoxaline ring, a benzimidazole ring, a perimidine ring or a quinazoline ring Can be mentioned.)
An amino group which may have a substituent [preferably an alkylamino group having one or more alkyl groups having 1 to 8 carbon atoms which may have a substituent (for example, methylamino, dimethylamino, diethylamino, A dibenzylamino group, etc.), and an arylamino group having an aromatic hydrocarbon group having 6 to 12 carbon atoms which may have a substituent (for example, phenylamino, diphenylamino, ditolylamino group, etc.). .)
Moreover, when the said substituent further has a substituent, the said exemplary substituent is mentioned as the substituent.

[7] Illustrative Examples Preferred specific examples of the organic compound of the present invention are shown below, but the present invention is not limited thereto.

^{First, -A 1 - (G 3 -A} 2) n - shows a specific example of.

Of ^{these, -A 1 - (G 3 -A} 2) n - preferably include the following: as.

Next, specific examples of T ¹ -G ¹ -and T ² -G ^2- are shown.

Of these, T ¹ -G ¹ -and T ² -G ^2- preferably include the following.

  Specific examples of the organic compound of the present invention represented by the formula (I) include the following.

[8] Synthesis Method The organic compound of the present invention can be synthesized using a known method by selecting raw materials according to the structure of the target compound.

  For example, as shown in the following reaction formula, the organic compound of the present invention can be obtained by repeating the reaction of an aromatic primary amine or aromatic secondary amine with an aromatic halide. The reaction between an aromatic primary amine or aromatic secondary amine and an aromatic halide proceeds, for example, by using a palladium catalyst or a copper catalyst in the presence of a base.

(In the above reaction formula, T ¹¹ and T ¹² correspond to T ¹ and T ² , G ^{11 to} G ¹³ correspond to G ^{1 to} G ³ , and Ar ^{21 to} Ar ²⁶ correspond to Ar ^{1 to} Ar ⁵ , respectively. (It is a halogen atom.)

In the above reaction formula, a linking group and a bridging group (such as -G ¹¹ -T ¹¹ ) are bonded to an aromatic primary amine or aromatic secondary amine and an aromatic halide, and then an aromatic tertiary amine moiety is bonded. Of course, a linking group and a bridging group (such as -G ¹¹ -T ¹¹ ) may be bonded after the aromatic tertiary amine moiety is formed.

  In addition, a known coupling reaction can be used. As a known coupling method, specifically, “Pallad Ium In Heterocycl Ic ChemIstry: A guIde for the Synthet Ic ChemIst” (Second Edition, 2002, JIe Jack LI and Gordon W. GrIbble, Pergamon), “Transition Metal Organic synthesis to open up its various reaction forms and latest results "(1997, Junjiro, Chemical Doujinsha)," Bolhard Shore under modern organic chemistry "(2004, KPC Vollhardt, Chemical Doujinsha) ) Or the like, or a coupling reaction between rings such as a coupling reaction between an aryl halide and an aryl borate).

  Methods for purifying compounds include “Separation and Purification Technology Handbook” (1993, edited by The Chemical Society of Japan), “Advanced separation of trace components and difficult-to-purify substances by chemical conversion method” (1988, IP Corporation). Issued by C.), or the methods described in the section “Separation and purification” of “Experimental Chemistry Course (4th edition) 1” (1990, edited by The Chemical Society of Japan) can be used. It is. Specifically, extraction (including suspension washing, boiling washing, ultrasonic washing, acid-base washing), adsorption, occlusion, melting, crystallization (including recrystallization from solvent, reprecipitation), distillation (atmospheric pressure) Distillation, vacuum distillation), evaporation, sublimation (atmospheric pressure sublimation, vacuum sublimation), ion exchange, dialysis, filtration, ultrafiltration, reverse osmosis, pressure osmosis, zone lysis, electrophoresis, centrifugation, flotation separation, sedimentation separation, Magnetic separation, various chromatography (shape classification: column, paper, thin layer, capillary, mobile phase classification: gas, liquid, micelle, supercritical fluid. Separation mechanism: adsorption, distribution, ion exchange, molecular sieve, chelate, gel filtration , Exclusion, affinity) and the like.

  Product confirmation and purity analysis methods include gas chromatograph (GC), high performance liquid chromatograph (HPLC), high speed amino acid analyzer (organic compound), capillary electrophoresis measurement (CE), size exclusion chromatograph (SEC). , Gel permeation chromatography (GPC), cross-fractionation chromatography (CFC), mass spectrometry (MS, LC / MS, GC / MS, MS / MS), nuclear magnetic resonance apparatus (NMR (1HNMR, 13CNMR)), Fourier transform Infrared spectrophotometer (FT-IR), UV-visible near-infrared spectrophotometer (UV.VIS, NIR), electron spin resonance apparatus (ESR), transmission electron microscope (TEM-EDX), electron beam microanalyzer (EPMA), Metal element analysis (ion chromatography, inductively coupled plasma-emission spectroscopy (ICP-AES) atomic absorption) Analysis (AAS), fluorescent X-ray analyzer (XRF)), nonmetal element analysis, trace analysis (ICP-MS, GF-AAS, optionally a GD-MS), etc., it is applicable.

[Organic electroluminescent material]
The organic electroluminescent element material of the present invention is composed of the organic compound of the present invention, and is mainly used in the composition for organic electroluminescent elements described later.

[Polymer compound]
The polymer compound of the present invention is obtained by polymerizing the organic compound of the present invention. For example, in the production of the organic electroluminescent element of the present invention described later, the composition for an organic electroluminescent element of the present invention is used. Formed.

[Composition for organic electroluminescence device]
The composition for organic electroluminescent elements of the present invention is usually used as a coating solution for forming an organic layer by a wet film-forming method in an organic electroluminescent element having an organic layer sandwiched between an anode and a cathode. . It is preferable that the composition for organic electroluminescent elements of the present invention is used for forming a hole transport layer in the organic layer.

  Here, when there is one layer between the anode and the light emitting layer in the organic electroluminescent element, this is referred to as a “hole transport layer”, and when there are two or more layers, the layer in contact with the anode is The “hole injection layer” and the other layers are collectively referred to as “hole transport layer”. In addition, layers provided between the anode and the light emitting layer may be collectively referred to as a “hole injection / transport layer”.

The composition for an organic electroluminescent device of the present invention is characterized by containing the organic compound of the present invention, and usually further contains a solvent.
The solvent is preferably a solvent that dissolves the organic compound of the present invention, and is usually a solvent that dissolves 0.05% by weight or more, preferably 0.5% by weight or more, more preferably 1% by weight or more of the organic compound.
In addition, the composition for organic electroluminescent elements of this invention may contain only 1 type of the organic compound of this invention, and may contain 2 or more types.
The composition for organic electroluminescent elements of the present invention usually contains the organic compound of the present invention in an amount of 0.01 to 50% by weight, preferably 0.05 to 20% by weight, more preferably 0.1 to 10% by weight. %contains.

  In addition, the composition for an organic electroluminescent device of the present invention may reduce the solubility of an electron-accepting compound and a hole transport layer described later, if necessary, and apply another layer on the hole transport layer. An additive such as an additive for accelerating the cross-linking reaction that enables the reaction may be included. In this case, as the solvent, a solvent that dissolves both the organic compound of the present invention and the additive by 0.05% by weight or more, preferably 0.5% by weight or more, more preferably 1% by weight or more may be used. preferable.

  Examples of the additive that accelerates the crosslinking reaction of the organic compound of the present invention contained in the composition for an organic electroluminescent element of the present invention include alkylphenone compounds, acylphosphine oxide compounds, metallocene compounds, oxime ester compounds, azo compounds, oniums. Examples thereof include polymerization initiators such as salts and polymerization accelerators, photosensitizers such as condensed polycyclic hydrocarbons, porphyrin compounds, and diaryl ketone compounds. These may be used alone or in combination of two or more.

  Moreover, as an electron-accepting compound contained in the composition for organic electroluminescent elements of this invention, it is 1 type or 2 of what was mentioned later as an electron-accepting compound contained in the positive hole injection layer of the organic electroluminescent element of this invention. More than seeds can be used.

  The solvent contained in the composition for organic electroluminescent elements of the present invention is not particularly limited, but it is necessary to dissolve the organic compound of the present invention, and preferably, toluene, xylene, methicylene, Aromatic compounds such as cyclohexylbenzene; halogen-containing solvents such as 1,2-dichloroethane, chlorobenzene, o-dichlorobenzene; fats such as ethylene glycol dimethyl ether, ethylene glycol diethyl ether, propylene glycol-1-monomethyl ether acetate (PGMEA) Ether, 1,2-dimethoxybenzene, 1,3-dimethoxybenzene, anisole, phenetole, 2-methoxytoluene, 3-methoxytoluene, 4-methoxytoluene, 2,3-dimethylanisole, 2,4-dimethylanisole, etc. Ether solvents such as aromatic ethers; aliphatic esters such as ethyl acetate, n-butyl acetate, ethyl lactate and n-butyl lactate; phenyl acetate, phenyl propionate, methyl benzoate, ethyl benzoate, isopropyl benzoate, benzoate And organic solvents such as ester solvents such as propyl acid and n-butyl benzoate. These may be used alone or in combination of two or more.

  The concentration of the solvent contained in the composition for organic electroluminescent elements of the present invention in the composition is usually 10% by weight or more, preferably 50% by weight or more, more preferably 80% by weight or more.

  In addition, it is widely known that moisture may promote deterioration of the performance of the organic electroluminescent element, particularly brightness reduction during continuous driving, in order to reduce moisture remaining in the coating film as much as possible. Among these solvents, those having a solubility of water at 25 ° C. of 1% by weight or less are preferable, and solvents having a solubility of 0.1% by weight or less are more preferable.

  Examples of the solvent contained in the composition for organic electroluminescent elements of the present invention include a solvent having a surface tension at 20 ° C. of less than 40 dyn / cm, preferably 36 dyn / cm or less, more preferably 33 dyn / cm or less.

  That is, when the layer containing the organic compound of the present invention is formed by a wet film formation method, the affinity with the base is important. The uniformity of the film quality greatly affects the uniformity and stability of the light emission of the organic electroluminescence device. Therefore, the coating solution used in the wet film-forming method has a surface that can form a uniform coating film with higher leveling properties. Low tension is required. By using such a solvent, a uniform layer containing the organic compound of the present invention can be formed.

  Specific examples of such a low surface tension solvent include the above-mentioned aromatic solvents such as toluene, xylene, methicylene, cyclohexylbenzene, ester solvents such as ethyl benzoate, ether solvents such as anisole, trifluoromethoxy, etc. Anisole, pentafluoromethoxybenzene, 3- (trifluoromethyl) anisole, ethyl (pentafluorobenzoate) and the like can be mentioned.

  The concentration of these solvents in the composition is usually 10% by weight or more, preferably 30% by weight or more, more preferably 50% by weight or more.

  Examples of the solvent contained in the composition for organic electroluminescence device of the present invention include a solvent having a vapor pressure at 25 ° C. of 10 mmHg or less, preferably 5 mmHg or less and usually 0.1 mmHg or more. By using such a solvent, it is possible to prepare a composition suitable for a process for producing an organic electroluminescent element by a wet film forming method and suitable for the properties of the organic compound of the present invention. Specific examples of such a solvent include the aromatic solvents such as toluene, xylene and methicylene, ether solvents and ester solvents described above. The concentration of these solvents in the composition is usually 10% by weight or more, preferably 30% by weight or more, more preferably 50% by weight or more.

  As a solvent contained in the composition for organic electroluminescent elements of the present invention, the vapor pressure at 25 ° C. is 2 mmHg or more, preferably 3 mmHg or more, more preferably 4 mmHg or more (however, the upper limit is preferably 10 mmHg or less). A mixed solvent of a certain solvent and a solvent having a vapor pressure at 25 ° C. of less than 2 mmHg, preferably 1 mmHg or less, more preferably 0.5 mmHg or less. By using such a mixed solvent, a homogeneous layer containing the organic compound of the present invention and further an electron accepting compound can be formed by a wet film forming method. The concentration of such a mixed solvent in the composition is usually 10% by weight or more, preferably 30% by weight or more, more preferably 50% by weight or more.

  Since the organic electroluminescent element is formed by laminating a plurality of layers made of organic compounds, it is very important that the film quality is uniform. When a layer is formed by a wet film formation method, a known film formation method such as a coating method such as a spin coating method or a spray method, or a printing method such as an ink jet method or a screen method can be adopted depending on the material and properties of the base. . For example, since the spray method is effective for forming a uniform film on a surface with unevenness, it is preferable when a layer made of an organic compound is provided on a surface where unevenness due to a patterned electrode or a partition between pixels remains. In the case of coating by the spray method, it is preferable that the coating liquid droplets sprayed from the nozzle to the coating surface be as small as possible because uniform film quality can be obtained. For that purpose, a solvent with high vapor pressure is mixed with the coating liquid, and a part of the solvent is volatilized from the sprayed coating droplet in the coating atmosphere, so that fine droplets are generated immediately before adhering to the substrate. Is preferred. Also, in order to obtain a more uniform film quality, it is necessary to secure time for the liquid film generated on the substrate to be leveled immediately after coating. In order to achieve this purpose, a slower drying solvent, that is, a vapor A technique in which a solvent having a low pressure is contained to some extent is used.

  Specific examples of the solvent having a vapor pressure at 25 ° C. of 2 mmHg or more and 10 mmHg or less include organic solvents such as xylene, anisole, cyclohexanone, and toluene. Examples of the solvent having a vapor pressure of less than 2 mmHg at 25 ° C. include ethyl benzoate, methyl benzoate, tetralin, and phenetole.

  The ratio of the mixed solvent is such that the solvent whose vapor pressure at 25 ° C. is 2 mmHg or more is 5% by weight or more, preferably 25% by weight or more, but less than 50% by weight, and the vapor pressure at 25 ° C. is 25% by weight. The solvent which is less than 2 mmHg is 30% by weight or more, preferably 50% by weight or more, particularly preferably 75% by weight or more, but less than 95% by weight in the total mixed solvent.

  In addition, since an organic electroluminescent element is formed by laminating a plurality of layers made of organic compounds, each layer is required to be a uniform layer. In the case of forming a layer by a wet film forming method, moisture may be mixed into the coating solution (composition) for forming the layer, so that moisture may be mixed into the coating film and the uniformity of the film may be impaired. It is preferable that the water content is as low as possible. Specifically, the amount of water contained in the organic electroluminescent element composition is preferably 1% by weight or less, more preferably 0.1% by weight or less, and still more preferably 0.05% by weight or less.

In general, since organic electroluminescent elements use many materials such as cathodes that deteriorate significantly due to moisture, the presence of moisture is not preferable from the viewpoint of element degradation. Examples of the method for reducing the amount of water in the solution include nitrogen gas sealing, use of a desiccant, dehydration of the solvent in advance, use of a solvent with low water solubility, and the like. In particular, it is preferable to use a solvent having low water solubility because the solution coating film can prevent whitening by absorbing moisture in the air during the coating process.
From such a viewpoint, the composition for organic electroluminescent elements of the present invention contains, for example, a solvent having a water solubility at 25 ° C. of 1% by weight or less (preferably 0.1% by weight or less) in the composition. It is preferable to contain 10% by weight or more. The solvent satisfying the above solubility condition is more preferably 30% by weight or more, and particularly preferably 50% by weight or more.

In addition, as a solvent contained in the composition for organic electroluminescent elements to which this embodiment is applied, various other solvents may be included as necessary in addition to the above-described solvents. Examples of such other solvents include amides such as N, N-dimethylformamide and N, N-dimethylacetamide; dimethyl sulfoxide and the like.
Moreover, the composition for organic electroluminescent elements of this invention may contain various additives, such as coating property improving agents, such as a leveling agent and an antifoamer.

[Film formation method]
As described above, since the organic electroluminescent element is formed by laminating a plurality of layers made of organic compounds, it is very important that the film quality is uniform. When a layer is formed by a wet film formation method, a known film formation method such as a coating method such as a spin coating method or a spray method, or a printing method such as an ink jet method or a screen method can be adopted depending on the material and properties of the base. .

When using a wet film-forming method, dissolve the organic compound of the present invention and other components used as necessary (electron-accepting compounds, additives that accelerate the crosslinking reaction, coatability improvers, etc.) in an appropriate solvent. The organic electroluminescent element composition is prepared. The composition containing the organic compound of the present invention is formed by applying this composition onto a layer corresponding to the lower layer of the layer to be formed by a technique such as spin coating or dip coating, and drying.
Usually, the layer formed using the composition for organic electroluminescent elements of the present invention is used as a hole transport layer. Therefore, this layer is usually formed on the hole injection layer or on the anode.

  In addition, in order to form a light emitting layer subsequent to the layer formed using the composition for organic electroluminescent elements of the present invention, the formed hole transport layer is dissolved in the coating composition for forming the light emitting layer. Preferably not. For this reason, after film-forming the composition for organic electroluminescent elements of this invention, the organic compound of this invention raise | generates a crosslinking reaction by heating and / or irradiation of electromagnetic energy, such as light, and the solubility of the film | membrane after reaction is reduced. It is preferable to make it.

  The heating method is not particularly limited, and examples thereof include heat drying and reduced pressure drying. As a condition in the case of heat drying, the layer formed using the composition for organic electroluminescent elements of the present invention is usually heated to 120 ° C. or higher, preferably 400 ° C. or lower. The heating time is usually 1 minute or longer, preferably 24 hours or shorter. Although it does not specifically limit as a heating means, Means, such as mounting the laminated body which has the formed layer on a hotplate, or heating in oven, is used. For example, conditions such as heating on a hot plate at 120 ° C. or more for 1 minute or more can be used.

  In the case of irradiation with electromagnetic energy such as light, a method of irradiating directly using an ultraviolet / visible / infrared light source such as an ultra-high pressure mercury lamp, a high-pressure mercury lamp, a halogen lamp or an infrared lamp, or the above-mentioned light source is incorporated. Examples include a mask aligner and a method of irradiation using a conveyor type light irradiation device. In electromagnetic energy irradiation other than light, for example, there is a method of irradiation using a device that irradiates a microwave generated by a magnetron, a so-called microwave oven.

  As the irradiation time, it is preferable to set conditions necessary for reducing the solubility of the film, but irradiation is usually performed for 0.1 seconds or longer, preferably 10 hours or shorter.

  Heating and irradiation of electromagnetic energy such as light may be performed individually or in combination. When combined, the order of implementation is not particularly limited.

  In order to reduce the amount of moisture contained in the layer and / or moisture adsorbed on the surface after implementation, the electromagnetic energy irradiation including heating and light is preferably performed in an atmosphere containing no moisture such as a nitrogen gas atmosphere. For the same purpose, when combined with heating and / or irradiation with electromagnetic energy such as light, it is particularly preferable to perform at least the step immediately before the formation of the organic light emitting layer in an atmosphere containing no moisture such as a nitrogen gas atmosphere.

[Organic electroluminescence device]
The organic electroluminescent device of the present invention has an anode and a cathode on a substrate, an organic layer between the anode and the cathode, and preferably a laminated structure in which an organic layer is formed by laminating a plurality of organic layers. It is. The organic layer of any one of the plurality of organic layers, preferably the hole transport layer is a layer containing the organic compound of the present invention described above or a layer containing the polymer compound of the present invention. Or is formed using a composition for an organic electroluminescence device containing the organic compound of the present invention.

  FIG. 1 is a cross-sectional view schematically showing an example of the structure of the organic electroluminescent element of the present invention. The organic electroluminescent device shown in FIG. 1 has an anode 2, a hole injection layer 3, a hole transport layer 4, an organic light emitting layer 5, a hole blocking layer 6, an electron injection layer 7 and a cathode 8 on a substrate 1. These are stacked in this order. In the case of this configuration, the hole transport layer 4 usually corresponds to the organic compound-containing layer of the present invention described above.

[1] Substrate The substrate 1 serves as a support for the organic electroluminescent element, and quartz or glass plates, metal plates, metal foils, plastic films, sheets, and the like are used. In particular, a glass plate or a transparent synthetic resin plate such as polyester, polymethacrylate, polycarbonate, or polysulfone is preferable. When using a synthetic resin substrate, it is necessary to pay attention to gas barrier properties. If the gas barrier property of the substrate is too small, the organic electroluminescent element may be deteriorated by the outside air that has passed through the substrate, which is not preferable. For this reason, a method of securing a gas barrier property by providing a dense silicon oxide film or the like on at least one surface of the synthetic resin substrate is also one of preferable methods.

[2] Anode The anode 2 plays the role of hole injection into a layer (hole injection layer 3 or organic light emitting layer 5) on the organic light emitting layer side described later. This anode 2 is usually a metal such as aluminum, gold, silver, nickel, palladium, platinum, a metal oxide such as an oxide of indium and / or tin, a metal halide such as copper iodide, carbon black, or A conductive polymer such as poly (3-methylthiophene), polypyrrole, or polyaniline is used. In general, the anode 2 is often formed by sputtering, vacuum deposition, or the like. Further, in the case of metal fine particles such as silver, fine particles such as copper iodide, carbon black, conductive metal oxide fine particles, and conductive polymer fine powders, they are dispersed in an appropriate binder resin solution and placed on the substrate 1. It is also possible to form the anode 2 by applying to. Further, in the case of a conductive polymer, a thin film can be directly formed on the substrate 1 by electrolytic polymerization, or the anode 2 can be formed by applying a conductive polymer on the substrate 1 (Applied Physics Letters, 1992). Year, Vol.60, pp.2711). The anode 2 can also be formed by stacking different materials.

  The thickness of the anode 2 varies depending on the required transparency. When transparency is required, it is desirable that the visible light transmittance is usually 60% or more, preferably 80% or more. In this case, the thickness is usually 5 nm or more, preferably 10 nm or more, Usually, it is 1000 nm or less, preferably 500 nm or less. If opaque, the anode 2 may be the same as the substrate 1. Furthermore, it is also possible to laminate different conductive materials on the anode 2 described above.

  In addition, the surface of the anode is treated with ultraviolet (UV) / ozone, oxygen plasma, or argon plasma for the purpose of removing impurities adhering to the anode and adjusting the ionization potential to improve the hole injection property. Is preferred. In addition, a known anode buffer layer is inserted between the hole injection layer 3 and the anode 2 for the purpose of further improving the efficiency of hole injection and improving the adhesion of the entire organic layer to the anode. Also good.

[3] Hole Injection Layer The hole injection layer 3 is a layer that transports holes from the anode 2 to the organic light emitting layer 5. Usually, this hole injection layer 3 is formed on the anode 2. Therefore, the hole injection layer 3 is preferably configured to contain a hole injection compound and an electron accepting compound. Furthermore, the hole injection layer 3 may contain other components without departing from the spirit of the present invention.

  Examples of the method for forming the hole injection layer 3 on the anode 2 include a wet film formation method and a vacuum deposition method. As described above, a uniform and defect-free thin film can be easily obtained. The wet film-forming method is preferable from the viewpoint that the time required for the preparation is short. In addition, ITO (indium tin oxide), which is generally used as the anode 2, has a surface roughness (Ra) of about 10 nm in addition to its surface, and often has local protrusions. There was a problem that defects were easily generated. Forming the hole injection layer 3 on the anode 2 by the wet film formation method reduces the occurrence of device defects due to the unevenness of the surface of the anode 2 as compared with the case of forming by the vacuum deposition method. It also has advantages.

  As the aromatic amine compound as the hole-injecting compound, a compound having a triarylamine structure is preferable, and a compound selected from compounds conventionally used as a material for forming a hole-injecting layer in an organic electroluminescent device is appropriately selected. Also good. As an aromatic amine compound, the binaphthyl type compound represented by following General formula (1) is mentioned, for example.

In the general formula (1), Ar ^{a to} Ar ^d are each independently a 5- or 6-membered aromatic hydrocarbon ring or aromatic heterocyclic monocyclic group or condensed ring group which may have a substituent. Ar ^a and Ar ^b , Ar ^c and Ar ^d may be bonded to each other to form a ring. W1 and W2 each represent an integer of 0 to 4, and W1 + W2 ≧ 1. X ¹ and X ² each independently represent a direct bond or a divalent linking group. In addition, the naphthalene ring in the general formula (1) may have an arbitrary substituent in addition to-(X ¹ NAr ^a Ar ^b ) and-(X ² NAr ^c Ar ^d ).

In the general formula (1), as the monocyclic group or condensed ring group of a 5- or 6-membered aromatic hydrocarbon ring or aromatic heterocyclic ring which may have a substituent of Ar ^{a to} Ar ^d , respectively. Independently, for example, a 5- or 6-membered monocyclic ring or a 2-3 condensed ring, specifically, a group derived from an aromatic hydrocarbon ring such as a phenyl group, a naphthyl group, an anthryl group; a pyridyl group, a thienyl group A group derived from an aromatic heterocycle such as Any of these may have a substituent.

As the substituent that Ar ^{a to} Ar ^d may have, those described later as the substituent that Ar ^{e to} Ar ^l may have, and an arylamino group (that is,-(NAr ^e Ar ^f ) described later, -(Corresponding to NAr ^g Ar ^h )).

Ar ^a and Ar ^b and / or Ar ^c and Ar ^d may be bonded to each other to form a ring. In this case, specific examples of the ring to be formed include a carbazole ring, a phenoxazine ring, an iminostilbene ring, a phenothiazine ring, an acridone ring, an acridine ring, an iminodibenzyl ring and the like that may have a substituent. Of these, a carbazole ring is preferred.

  In the general formula (1), W1 and W2 each represent an integer of 0 to 4, and W1 + W2 ≧ 1. Particularly preferred are W1 = 1 and W2 = 1. The arylamino groups in the case where W1 and / or W2 is 2 or more may be the same or different.

X ¹ and X ² each independently represent a direct bond or a divalent linking group. Although there is no restriction | limiting in particular as a bivalent coupling group, For example, what is shown below etc. are mentioned. A direct bond is particularly preferable as X ¹ and X ² .

In addition to — (X ¹ NAr ^a Ar ^b ) and — (X ² NAr ^c Ar ^d ), the naphthalene ring in the general formula (1) has one or more arbitrary substituents at an arbitrary position. It may be. Preferred examples of such a substituent include a halogen atom, a hydroxyl group, an alkyl group which may have a substituent, an alkoxy group which may have a substituent, and an alkenyl group which may have a substituent. , One or more substituents selected from the group consisting of optionally substituted alkoxycarbonyl groups. Of these, an alkyl group is particularly preferred.

As binaphthyl compound represented by the general formula (1), as represented by the following general formula (1-1), Ar ^a and Ar ^c is preferably binaphthyl compound substituted by further respective arylamino group .

（一般式（１−１）中、Ａｒ^ｅ〜Ａｒ^ｌは各々独立に、置換基を有していてもよい５または６員環の芳香族炭化水素環または芳香族複素環の単環基または縮合環基を表し、Ａｒ^ｅとＡｒ^ｆ、Ａｒ^ｇとＡｒ^ｈは各々結合して環を形成していてもよい。Ｗ１およびＷ２は一般式（１）におけるのと同義である。Ｘ^１およびＸ^２は一般式（１）におけるのと同義である。）

(In the general formula (1-1), Ar ^{e to} Ar ¹ each independently represents a 5- or 6-membered aromatic hydrocarbon ring or aromatic monocyclic group which may have a substituent, or Represents a condensed ring group, Ar ^e and Ar ^f , Ar ^g and Ar ^h may be bonded to each other to form a ring, W 1 and W 2 have the same meanings as in formula (1), X ¹ and X ² has the same meaning as in general formula (1).)

In the general formula (1-1), the naphthalene ring includes substituents-(X ¹ NAr ⁱ Ar ^j NAr ^f Ar ^e ) and-(X ² NAr ^k Ar ^l NAr ^g each containing an arylamino group bonded to the naphthalene ring. In addition to Ar ^h ), it may have an arbitrary substituent. In addition, these substituents — (X ¹ NA ⁱ Ar ^j NAr ^f Ar ^e ) and — (X ² NAr ^k Ar ^l NAr ^g Ar ^h ) have a substituent at any substitution position of the naphthalene ring. Also good. Especially, the binaphthyl type compound substituted to 4-position and 4'-position of the naphthalene ring in General formula (1-1) respectively is more preferable.

  Moreover, as a high molecular compound which has a positive hole transport site | part in a molecule | numerator used as a hole injectable compound, the high molecular compound which contains an aromatic tertiary amino group in a main skeleton as a structural unit is mentioned, for example. Specific examples thereof include a hole injecting compound having a structure represented by the following general formula (2) as a repeating unit.

（式（２）中、Ａｒ^４４〜Ａｒ^４８は、各々独立して置換基を有していてもよい２価の芳香族環基を示し、Ｒ^３１〜Ｒ^３２は、各々独立して置換基を有していてもよい１価の芳香族環基を示し、Ｑは直接結合、または下記の連結基から選ばれる。なお、「芳香族環基」とは、「芳香族炭化水素環由来の基」および「芳香族複素環由来の基」の両方を含む。）

（式（３）中、Ａｒ^４９は置換基を有していてもよい２価の芳香族環基を示し、Ａｒ^５０は置換基を有していてもよい１価の芳香族環基を示す。）

(In the formula (2), Ar ^{44 to} Ar ⁴⁸ each independently represents a divalent aromatic ring group which may have a substituent, and R ^{31 to} R ³² each independently represents a substituent. And Q is selected from a direct bond or the following linking group, wherein “aromatic ring group” means “derived from an aromatic hydrocarbon ring” Including "group" and "group derived from an aromatic heterocycle")

(In formula (3), Ar ⁴⁹ represents a divalent aromatic ring group which may have a substituent, and Ar ⁵⁰ represents a monovalent aromatic ring group which may have a substituent. .)

In the general formula (2), Ar ^{44 to} Ar ⁴⁸ are each preferably a group derived from a divalent benzene ring, naphthalene ring, anthracene ring or biphenyl group which may each independently have a substituent, A group derived from a benzene ring is preferred. Examples of the substituent include a halogen atom; a linear or branched alkyl group having 1 to 6 carbon atoms such as a methyl group and an ethyl group; an alkenyl group such as a vinyl group; and a C 2-7 such as a methoxycarbonyl group and an ethoxycarbonyl group. A linear or branched alkoxycarbonyl group of 1 to 6 carbon atoms such as a methoxy group or an ethoxy group; an aryloxy group of 6 to 12 carbon atoms such as a phenoxy group or a benzyloxy group; And a dialkylamino group having an alkyl chain having 1 to 6 carbon atoms such as a diisopropylamino group. Of these, an alkyl group having 1 to 3 carbon atoms is preferable, and a methyl group is particularly preferable. Most preferably, Ar ^{44 to} Ar ⁴⁸ are each an unsubstituted aromatic ring group.

R ³¹ and R ³² are preferably each independently a phenyl group, naphthyl group, anthryl group, pyridyl group, triazyl group, pyrazyl group, quinoxalyl group, thienyl group, or biphenyl group, which may have a substituent. Preferably a phenyl group, a naphthyl group or a biphenyl group, more preferably a phenyl group. Examples of the substituent include a group in which an aromatic ring in Ar ⁴⁴ to Ar ⁴⁸ may have include the same groups as previously described.

In the general formula (3), Ar ⁴⁹ is a divalent aromatic ring group which may have a substituent, preferably an aromatic hydrocarbon ring group from the viewpoint of hole transportability. Includes an optionally substituted divalent benzene ring, naphthalene ring, anthracene ring-derived group, biphenylene group, and terphenylene group. Further, examples of the substituent include a group in which an aromatic ring may have at Ar ⁴⁴ to Ar ^48, include the same groups as previously described. Of these, an alkyl group having 1 to 3 carbon atoms is preferable, and a methyl group is particularly preferable.

Ar ⁵⁰ is an aromatic ring group which may have a substituent, preferably an aromatic hydrocarbon ring group from the viewpoint of hole transportability, and specifically, phenyl which may have a substituent. Group, naphthyl group, anthryl group, pyridyl group, triazyl group, pyrazyl group, quinoxalyl group, thienyl group, biphenyl group and the like. As this substituent, the group similar to the group mentioned above is mentioned as a group which the aromatic ring in Ar < ⁴⁴ > -Ar < ⁴⁸ > of General formula (2) may have.

In the general formula (3), it is most preferable that Ar ⁴⁹ and Ar ⁵⁰ are both unsubstituted aromatic ring groups.

  Examples of the hole-injecting compound containing an aromatic tertiary amino group as a side chain include compounds having a repeating unit having a structure represented by the following general formulas (4) and (5).

（式（４）中、Ａｒ^５１は置換基を有していてもよい２価の芳香族環基を示し、Ａｒ^５２〜Ａｒ^５３は、各々独立して置換基を有していてもよい１価の芳香族環基を示し、Ｒ^３３〜Ｒ^３５は、各々独立して水素原子、ハロゲン原子、アルキル基、アルコキシ基、置換基を有していてもよい１価の芳香族環基を示す。）

(In formula (4), Ar ⁵¹ represents a divalent aromatic ring group which may have a substituent, and Ar ^{52 to} Ar ⁵³ may each independently have a substituent 1. R ^{33 to} R ³⁵ each independently represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, or a monovalent aromatic ring group which may have a substituent. .)

（式（５）中、Ａｒ^５４〜Ａｒ^５８は、各々独立して置換基を有していてもよい２価の芳香族環基を示し、Ｒ^３６およびＲ^３７は、各々独立して置換基を有していてもよい芳香族環基を示し、Ｙは直接結合、または下記の連結基から選ばれる。）

(In the formula (5), Ar ^{54 to} Ar ⁵⁸ each independently represent a divalent aromatic ring group which may have a substituent, and R ³⁶ and R ³⁷ each independently represent a substituent. And Y is selected from a direct bond or the following linking group.)

In the general formula (4), Ar ⁵¹ is preferably a divalent benzene ring, a naphthalene ring, a group derived from an anthracene ring, or a biphenylene group each optionally having a substituent. For example, examples of the group that the aromatic ring in Ar ^{44 to} Ar ⁴⁸ in the general formula (2) described above may have include the same groups as those described above, and preferred groups are also the same.

Ar ⁵² and Ar ⁵³ are preferably each independently a phenyl group, a naphthyl group, an anthryl group, a pyridyl group, a triazyl group, a pyrazyl group, a quinoxalyl group, a thienyl group, and a biphenyl group, and these include a substituent group. May have. Examples of the substituent include the same groups as those described above as the group that the aromatic ring in Ar ^{44 to} Ar ⁴⁸ of the general formula (2) may have, and preferred groups are also the same.

R ^{33 to} R ³⁵ are preferably each independently a hydrogen atom; a halogen atom; a linear or branched alkyl group having 1 to 6 carbon atoms such as a methyl group or an ethyl group; a carbon such as a methoxy group or an ethoxy group. A linear or branched alkoxy group of 1 to 6; a phenyl group; or a tolyl group.

In the general formula (5), Ar ^{54 to} Ar ⁵⁸ are preferably a divalent benzene ring, a naphthalene ring, a group derived from an anthracene ring, or a biphenylene group, each of which may have a substituent. A group derived from a benzene ring. Examples of the substituent include the same groups as those described above as the groups that the aromatic ring in Ar ^{44 to} Ar ⁴⁸ of formula (2) may have, and preferred groups are also the same.

R ³⁶ and R ³⁷ are each preferably a phenyl group, a naphthyl group, an anthryl group, a pyridyl group, a triazyl group, a pyrazyl group, a quinoxalyl group, a thienyl group, or a biphenyl group, each of which may have a substituent. . Examples of the substituent include the same groups as those described above as the groups that the aromatic ring in Ar ^{44 to} Ar ⁴⁸ of formula (2) may have, and preferred groups are also the same.

  Preferred examples of the structures represented by the general formulas (2) to (5) are shown below, but are not limited thereto.

  The hole injecting compound which is a polymer compound having a hole transporting site in the molecule is most preferably a homopolymer having a structure represented by any one of the general formulas (2) to (5). It may be a copolymer (copolymer) with any monomer. When it is a copolymer, it is preferable to contain 50 mol% or more, especially 70 mol% or more of the structural units represented by the general formulas (2) to (5). In addition, the hole injectable material which is a high molecular compound may contain multiple types of structures represented by the general formulas (2) to (5) in one compound. Moreover, you may use in combination of multiple types of the compound containing the structure represented by General formula (2)-(5). Of the general formulas (2) to (5), a homopolymer composed of a repeating unit represented by the general formula (2) is particularly preferable.

  Examples of the hole injecting material made of a polymer compound further include conjugated polymers. For this purpose, polyfluorene, polypyrrole, polyaniline, polythiophene, polyparaphenylene vinylene are preferred.

Next, the electron accepting compound will be described.
Examples of the electron accepting compound contained in the hole injection layer include triaryl boron compounds, metal halides, Lewis acids, organic acids, onium salts, salts of arylamines and metal halides, arylamines and Lewis acids. And one or more compounds selected from the group consisting of salts with These electron-accepting compounds are used by mixing with a hole-injecting material, and the conductivity of the hole-injecting layer can be improved by oxidizing the hole-injecting material.

  Examples of the triarylboron compound as the electron-accepting compound include boron compounds represented by the following general formula (6). The boron compound represented by the general formula (6) is preferably a Lewis acid. The electron affinity of the boron compound is usually 4 eV or more, preferably 5 eV or more.

In the general formula (6), preferably, Ar ^{101 to} Ar ¹⁰³ are each independently a monocyclic 5- or 6-membered ring such as a phenyl group, a naphthyl group, an anthryl group, or a biphenyl group that may have a substituent, Or an aromatic hydrocarbon ring group formed by condensing and / or directly bonding 2 to 3 thereof; or 5 or 6 such as a thienyl group, pyridyl group, triazyl group, pyrazyl group, quinoxalyl group, etc., which may have a substituent. It represents a single-membered ring or an aromatic heterocyclic group formed by condensing 2 or 3 of these and / or directly bonding them.

Examples of the substituent that Ar ^{101 to} Ar ¹⁰³ may have include a halogen atom; an alkyl group; an alkenyl group; an alkoxycarbonyl group; an alkoxy group; an aryloxy group; an acyl group; a haloalkyl group;

In particular, at least one of Ar ^{101 to} Ar ¹⁰³ is preferably a substituent having a positive Hammett constant (σ _m and / or σ _p ), and Ar ^{101 to} Ar ¹⁰³ are all Hammett constants (σ It is particularly preferred that _m and / or σ _p ) is a substituent showing a positive value. By having such an electron-withdrawing substituent, the electron acceptability of these compounds is improved. Ar ^{101 to} Ar ¹⁰³ are more preferably an aromatic hydrocarbon group or an aromatic heterocyclic group substituted with a halogen atom.

  Although the preferable specific example of the boron compound represented by General formula (6) is shown to the following 6-1 to 6-17, it is not limited to these.

  Of these, the following compounds are particularly preferred.

  Examples of the electron-accepting compound include onium salts described in WO2005 / 089024, and preferred examples thereof are the same, but the following compounds are particularly preferred.

  The thickness of the hole injection layer 3 is usually 5 nm or more, preferably 10 nm or more, and usually 1000 nm or less, preferably 500 nm or less.

  The content of the electron-accepting compound in the hole-injecting layer 3 with respect to the hole-injecting compound is usually 0.1 mol% or more, preferably 1 mol% or more. However, it is usually 100 mol% or less, preferably 40 mol% or less.

[4] Hole transport layer The hole transport layer 4 has a function of injecting holes injected in the order of the anode 2 and the hole injection layer 3 into the organic light emitting layer 5, and electrons from the light emitting layer 5 are anode 2. It has a function of suppressing a decrease in luminous efficiency caused by being injected into the side.

  In order to exhibit this function, the hole transport layer 4 is formed using the organic compound of the present invention or the polymer compound of the present invention, or using the composition for organic electroluminescent elements containing the organic compound of the present invention. It is preferable that it is a layer. That is, the organic compound of the present invention is preferably used as a hole transporting compound.

The hole transport layer is formed by the method described in [Film Formation Method].
The film thickness 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.

[5] Organic Light-Emitting Layer The organic light-emitting layer 5 is usually provided on the hole transport layer 4. The organic light-emitting layer 5 includes holes injected from the anode 2 through the hole injection layer 3 and the hole transport layer 4 between the electrodes to which an electric field is applied, and an electron injection layer 7 and a hole blocking layer 6 from the cathode 8. It is a layer that is excited by recombination with electrons injected through and becomes a main light emitting source.

  The organic light emitting layer 5 contains at least a material having a light emitting property (light emitting material), and preferably has a material having a hole transporting property (hole transporting compound) or an electron transporting property. Material (electron transporting compound). Furthermore, the organic light emitting layer 5 may contain other components without departing from the spirit of the present invention. As these materials, from the viewpoint of forming the organic light emitting layer 5 by a wet film formation method as described later, it is preferable to use any low molecular weight materials.

  Any known material can be applied as the light emitting material. For example, a fluorescent material or a phosphorescent material may be used, but a phosphorescent material is preferable from the viewpoint of internal quantum efficiency.

  In order to improve the solubility in a solvent, it is also important to reduce the symmetry and rigidity of the molecules of the luminescent material, or to introduce a lipophilic substituent such as an alkyl group.

  Examples of fluorescent dyes that emit blue light include perylene, pyrene, anthracene, coumarin, p-bis (2-phenylethenyl) benzene, and derivatives thereof. Examples of the green fluorescent dye include quinacridone derivatives and coumarin derivatives. Examples of yellow fluorescent dyes include rubrene and perimidone derivatives. Examples of red fluorescent dyes include DCM (4- (dicyanomethylene) -2-methyl-6- (p-dimethylaminostyryl) -4H-pyran) compounds, benzopyran derivatives, rhodamine derivatives, benzothioxanthene derivatives, azabenzothioxanthene, etc. Can be mentioned.

  As the phosphorescent material, for example, a long-period type periodic table (hereinafter referred to as a long-period type periodic table when referred to as “periodic table” unless otherwise specified) is selected from the seventh to eleventh groups. And an organometallic complex containing a metal.

  Preferred examples of the metal selected from Groups 7 to 11 of the periodic table contained in the phosphorescent organometallic complex include ruthenium, rhodium, palladium, silver, rhenium, osmium, iridium, platinum, and gold. Preferred examples of these organometallic complexes include compounds represented by the following formula (III) or formula (IV).

ML _(q−j) L ′ _j (III)
(In formula (III), M represents a metal, q represents the valence of the metal, L and L ′ represent a bidentate ligand, and j represents a number of 0, 1 or 2. )

（式（IV）中、Ｍ^７は金属を表し、Ｔは炭素原子または窒素原子を表す。Ｒ^９２〜Ｒ^９５は、それぞれ独立に置換基を表す。但し、Ｔが窒素原子の場合は、Ｒ^９４およびＲ^９５は無い。）

(In the formula (IV), M ⁷ represents a metal, T represents a carbon atom or a nitrogen atom. R ^{92 to} R ⁹⁵ each independently represents a substituent. However, when T is a nitrogen atom, R 7 ⁹⁴ and R ⁹⁵ are not.)

Hereinafter, the compound represented by the formula (III) will be described first.
In formula (III), M represents an arbitrary metal, and specific examples of preferable ones include the metals described above as metals selected from Groups 7 to 11 of the periodic table.

（上記Ｌの部分構造において、環Ａ１は、置換基を有していてもよい、芳香族炭化水素基または芳香族複素環基を表す。） Moreover, in formula (III), the bidentate ligand L shows the ligand which has the following partial structures.

(In the partial structure of L, ring A1 represents an aromatic hydrocarbon group or an aromatic heterocyclic group which may have a substituent.)

  Examples of the aromatic hydrocarbon group include a 5- or 6-membered monocyclic ring or a 2-5 condensed ring. Specific examples include monovalent groups derived from a 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, etc. Is mentioned.

  Examples of the aromatic heterocyclic group include a 5- or 6-membered monocyclic ring or a 2-4 condensed ring. Specific examples include 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, thienofuran ring, benzoisoxazole ring, benzisothiazole ring, benzimidazole ring, pyridine ring, pyrazine ring, pyridazine ring, pyrimidine ring, triazine ring, quinoline ring, isoquinoline ring , Sinoline ring, quinoxaline ring, phenanthridine ring, benzimidazole ring, perimidine ring, quinazoline ring, quinazolinone ring, monovalent group derived from an azulene ring, and the like.

  In the partial structure of L, ring A2 represents a nitrogen-containing aromatic heterocyclic group which may have a substituent.

  Examples of the nitrogen-containing aromatic heterocyclic group include groups derived from a 5- or 6-membered monocyclic ring or a 2-4 condensed ring. Specific examples include pyrrole ring, pyrazole ring, imidazole ring, oxadiazole ring, indole ring, carbazole ring, pyrroloimidazole ring, pyrrolopyrazole ring, pyrrolopyrrole ring, thienopyrrole ring, furopyrrole ring, thienofuran ring, benzoisoxazole ring. , Benzisothiazole ring, benzimidazole ring, pyridine ring, pyrazine ring, pyridazine ring, pyrimidine ring, triazine ring, quinoline ring, isoquinoline ring, quinoxaline ring, phenanthridine ring, benzimidazole ring, perimidine ring, quinazoline ring, quinazolinone Examples thereof include a monovalent group derived from a ring.

  Examples of the substituent that each of ring A1 and ring A2 may have include a halogen atom; an alkyl group; an alkenyl group; an alkoxycarbonyl group; an alkoxy group; an aryloxy group; a dialkylamino group; Acyl group; haloalkyl group; cyano group; aromatic hydrocarbon group and the like.

  In the formula (III), the bidentate ligand L ′ represents a ligand having the following partial structure. However, in the following formulae, “Ph” represents a phenyl group.

  Among these, as L ′, the following ligands are preferable from the viewpoint of the stability of the complex.

  More preferable examples of the compound represented by the formula (III) include compounds represented by the following formulas (IIIa), (IIIb), and (IIIc).

（式（IIIａ）中、Ｍ^４は、Ｍと同様の金属を表し、ｗは、上記金属の価数を表し、環Ａ１は、置換基を有していてもよい芳香族炭化水素基を表し、環Ａ２は、置換基を有していてもよい含窒素芳香族複素環基を表す。）

(In formula (IIIa), M ⁴ represents the same metal as M, w represents the valence of the metal, and ring A1 represents an aromatic hydrocarbon group which may have a substituent. Ring A2 represents a nitrogen-containing aromatic heterocyclic group which may have a substituent.

（式（IIIｂ）中、Ｍ^５は、Ｍと同様の金属を表し、ｗは、上記金属の価数を表し、環Ａ１は、置換基を有していてもよい芳香族炭化水素基または芳香族複素環基を表し、環Ａ２は、置換基を有していてもよい含窒素芳香族複素環基を表す。）

(In formula (IIIb), M ⁵ represents the same metal as M, w represents the valence of the metal, and ring A1 represents an aromatic hydrocarbon group or aromatic group which may have a substituent. Represents a heterocyclic group, and ring A2 represents a nitrogen-containing aromatic heterocyclic group which may have a substituent.)

（式（IIIｃ）中、Ｍ^６は、Ｍと同様の金属を表し、ｗは、上記金属の価数を表し、ｊは、０、１または２を表し、環Ａ１および環Ａ１′は、それぞれ独立に、置換基を有していてもよい芳香族炭化水素基または芳香族複素環基を表し、環Ａ２および環Ａ２′は、それぞれ独立に、置換基を有していてもよい含窒素芳香族複素環基を表す。）

(In formula (IIIc), M ⁶ represents the same metal as M, w represents the valence of the metal, j represents 0, 1 or 2, and ring A1 and ring A1 ′ each represent Independently represents an optionally substituted aromatic hydrocarbon group or aromatic heterocyclic group, and ring A2 and ring A2 ′ are each independently a nitrogen-containing aromatic optionally having a substituent. Represents a heterocyclic group.)

In the above formulas (IIIa), (IIIb) and (IIIc), preferred examples of ring A1 and ring A1 ′ include phenyl group, biphenyl group, naphthyl group, anthryl group, thienyl group, furyl group, benzothienyl group, benzofuryl group. Group, pyridyl group, quinolyl group, isoquinolyl group, carbazolyl group and the like.

  In the above formulas (IIIa) to (IIIc), preferred examples of ring A2 and ring A2 ′ include pyridyl group, pyrimidyl group, pyrazyl group, triazyl group, benzothiazole group, benzoxazole group, benzimidazole group, quinolyl group, An isoquinolyl group, a quinoxalyl group, a phenanthridyl group, and the like can be given.

  Examples of the substituent that the compounds represented by the formulas (IIIa) to (IIIc) may have include a halogen atom; an alkyl group; an alkenyl group; an alkoxycarbonyl group; an alkoxy group; an aryloxy group; A diarylamino group; a carbazolyl group; an acyl group; a haloalkyl group; a cyano group, and the like.

  These substituents may be connected to each other to form a ring. As a specific example, a substituent of the ring A1 and a substituent of the ring A2 are bonded, or a substituent of the ring A1 ′ and a substituent of the ring A2 ′ are bonded. Two fused rings may be formed. Examples of such a condensed ring include a 7,8-benzoquinoline group.

  Among these, as a substituent for ring A1, ring A1 ′, ring A2 and ring A2 ′, an alkyl group, alkoxy group, aromatic hydrocarbon group, cyano group, halogen atom, haloalkyl group, diarylamino group, carbazolyl are more preferable. Groups.

In addition, preferable examples of M ^{4 to} M ⁶ in the formulas (IIIa) to (IIIc) include ruthenium, rhodium, palladium, silver, rhenium, osmium, iridium, platinum, or gold.

  Specific examples of the organometallic complexes represented by the above formulas (III) and (IIIa) to (IIIc) are shown below, but are not limited to the following compounds.

  Among the organometallic complexes represented by the above formula (III), in particular, as the ligand L and / or L ′, a 2-arylpyridine-based ligand, that is, 2-arylpyridine, there is an optional substituent. The compound which has what was couple | bonded and the thing formed by arbitrary groups condensing to this is preferable.

  The compounds described in International Patent Publication No. 2005/019373 can also be used as the light emitting material.

Next, the compound represented by formula (IV) will be described.
In formula (IV), M ⁷ represents a metal. Specific examples include the metals described above as the metal selected from Groups 7 to 11 of the periodic table. Among these, ruthenium, rhodium, palladium, silver, rhenium, osmium, iridium, platinum or gold is preferable, and divalent metals such as platinum and palladium are particularly preferable.

In the formula (IV), 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, 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;

Further, when T is carbon ^{atom, R 94} and ^{R 95} each independently ^represents a substituent represented by the same exemplary compounds and ^{R 92} and ^{R 93.} Also, if T is a nitrogen ^{atom, R 94,} and ^{R 95} is not.

R ^{92 to} R ⁹⁵ may further have a substituent. When it has a substituent, there is no restriction | limiting in particular in the kind, Arbitrary groups can be made into a substituent.
Further, any two or more groups of R ^{92 to} R ⁹⁵ may be connected to each other to form a ring.

  Specific examples (T-1, T-10 to T-15) of the organometallic complex represented by the formula (IV) are shown below, but are not limited to the following examples. In the following chemical formulae, Me represents a methyl group, and Et represents an ethyl group.

  In the present invention, the molecular weight of the compound used as the light emitting material is usually 10,000 or less, preferably 5000 or less, more preferably 4000 or less, still more preferably 3000 or less, and usually 100 or more, preferably 200 or more, more preferably 300 or more. More preferably, the range is 400 or more. If the molecular weight is less than 100, the heat resistance is remarkably reduced, gas is generated, the film quality is deteriorated when the film is formed, or the morphology of the organic electroluminescent element is changed due to migration or the like. This is not preferable. If the molecular weight exceeds 10,000, it is not preferable because it is difficult to purify the organic compound or it takes time to dissolve the organic compound in a solvent.

  The light emitting layer may contain any one of the various light emitting materials described above alone, or may contain two or more kinds in any combination and ratio.

  Examples of the low molecular weight hole transporting compound include various compounds exemplified as the hole transporting compound of the hole transporting layer, and 4,4′-bis [N- (1-naphthyl)- N-phenylamino] biphenyl, an aromatic diamine containing two or more tertiary amines and having two or more condensed aromatic rings substituted with nitrogen atoms (Japanese Patent Laid-Open No. 5-234811), 4,4 An aromatic amine compound having a starburst structure such as', 4 "-tris (1-naphthylphenylamino) triphenylamine (Journal of Luminescence, 1997, Vol.72-74, pp.985), Spiro compounds such as aromatic amine compounds comprising tetramers (Chemical Communications, 1996, pp. 2175), 2,2 ′, 7,7′-tetrakis- (diphenylamino) -9,9′-spirobifluorene (Synthetic Metals, 1 997, Vol.91, pp.209).

  Examples of low molecular weight electron transport compounds include 2,5-bis (1-naphthyl) -1,3,4-oxadiazole (BND) and 2,5-bis (6 ′-(2 ′). , 2 "-bipyridyl))-1,1-dimethyl-3,4-diphenylsilole (PyPySPyPy), bathophenanthroline (BPhen), 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline ( BCP, bathocuproine), 2- (4-biphenylyl) -5- (p-tertiarybutylphenyl) -1,3,4-oxadiazole (tBu-PBD), 4,4′-bis (9-carbazole) ) -Biphenyl (CBP) and the like.

  These hole transporting compounds and electron transporting compounds are preferably used as host materials in the light-emitting layer, but specifically, the following compounds can be used as host materials.

  Examples of the method for forming the organic light emitting layer 5 include a wet film forming method and a vacuum evaporation method. As described above, a homogeneous and defect-free thin film can be easily obtained, and the time for formation is short. The wet film-forming method is preferable from the viewpoint that the effect of insolubilization of the hole transport layer 4 by the organic compound of the present invention can be enjoyed. When the organic light emitting layer 5 is formed by a wet film formation method, the above-described material is dissolved in an appropriate solvent to prepare a coating solution, which is applied and formed on the hole transport layer 4 after the above formation. And drying to remove the solvent. The formation method is the same as the formation method of the hole transport layer.

  The film thickness of the organic light emitting layer 5 is usually 3 nm or more, preferably 5 nm or more, and usually 200 nm or less, preferably 100 nm or less.

[6] Hole blocking layer In FIG. 1, the hole blocking layer 6 is provided between the organic light emitting layer 5 and the electron transport layer 7, but the hole blocking layer 6 may be omitted.
The hole blocking layer 6 is laminated on the organic light emitting layer 5 so as to be in contact with the interface of the organic light emitting layer 5 on the cathode 8 side, but the holes moving from the anode 2 reach the cathode 8. And a compound capable of efficiently transporting electrons injected from the cathode 8 toward the organic light emitting layer 5.

  The physical properties required for the material constituting the hole blocking layer 6 include high electron mobility, low hole mobility, a large energy gap (difference between HOMO and LUMO), and excited triplet level (T1). Is high.

  As hole blocking materials satisfying such conditions, mixed materials such as bis (2-methyl-8-quinolinolato), (phenolato) aluminum, bis (2-methyl-8-quinolinolato), (triphenylsilanolato) aluminum, etc. Ligand complexes, metal complexes such as bis (2-methyl-8-quinolato) aluminum-μ-oxo-bis- (2-methyl-8-quinolinato) aluminum binuclear metal complexes, and styryl compounds such as distyrylbiphenyl derivatives (JP-A-11-242996), triazole derivatives such as 3- (4-biphenylyl) -4-phenyl-5 (4-tert-butylphenyl) -1,2,4-triazole (JP-A-7-41759) And phenanthroline derivatives such as bathocuproine (Japanese Patent Laid-Open No. 10-79297). Furthermore, compounds having at least one pyridine ring substituted at the 2,4,6-position described in International Publication No. 2005-022962 are also preferable as the hole blocking material.

Specific examples include the compounds described below.

  Similarly to the hole injection layer 3 and the organic light emitting layer 5, the hole blocking layer 6 can also be formed by a wet film formation method, but is usually formed by a vacuum deposition method. The details of the procedure of the vacuum deposition method are the same as those of the electron injection layer 7 described later.

  The film thickness of the hole blocking layer 6 is usually 0.5 nm or more, preferably 1 nm or more, and usually 100 nm or less, preferably 50 nm or less.

[7] Electron Injection Layer The electron injection layer 7 plays a role of efficiently injecting electrons injected from the cathode 8 into the organic light emitting layer 5.
In order to perform electron injection efficiently, the material for forming the electron injection layer 7 is preferably a metal having a low work function. Examples include alkali metals such as sodium and cesium, and alkaline earth metals such as barium and calcium. The film thickness is usually preferably from 0.1 nm to 5 nm.

  Further, organic electron transport materials represented by metal complexes such as nitrogen-containing heterocyclic compounds such as bathophenanthroline and aluminum complexes of 8-hydroxyquinoline described later are doped with alkali metals such as sodium, potassium, cesium, lithium and rubidium. (Described in JP-A-10-270171, JP-A 2002-1000047, JP-A 2002-1000048, and the like) makes it possible to improve electron injection / transport properties and achieve excellent film quality. Therefore, it is preferable. The film thickness in this case is usually in the range of 5 nm or more, preferably 10 nm or more, and usually 200 nm or less, preferably 100 nm or less.

  The electron injection layer 7 is formed by laminating on the organic light emitting layer 5 or the hole blocking layer 6 thereon by a wet film formation method or a vacuum deposition method.

Details of the wet film forming method are the same as those of the hole injection layer 3 and the organic light emitting layer 5.
On the other hand, in the case of the vacuum vapor deposition method, the vapor deposition source is put into a crucible or a metal boat installed in the vacuum vessel, and the inside of the vacuum vessel is evacuated to about 10 ⁻⁴ Pa with an appropriate vacuum pump, and then the crucible or metal The boat is heated and evaporated to form the electron injection layer 7 on the organic light emitting layer 5 or the hole blocking layer 6 on the substrate placed facing the crucible or the metal boat.

The alkali metal as the electron injection layer is deposited by using an alkali metal dispenser in which nichrome is filled with an alkali metal chromate and a reducing agent. By heating the dispenser in a vacuum container, the alkali metal chromate is reduced and the alkali metal is evaporated. In the case of co-evaporating the organic electron transport material and the alkali metal, the organic electron transport material is put in a crucible installed in a vacuum vessel, and the inside of the vacuum vessel is evacuated to about 10 ⁻⁴ Pa with a suitable vacuum pump. Each crucible and dispenser are simultaneously heated and evaporated to form an electron injection layer 7 on the substrate placed facing the crucible and dispenser.
At this time, co-evaporation is uniformly performed in the film thickness direction of the electron injection layer 7, but there may be a concentration distribution in the film thickness direction.

[8] Cathode The cathode 8 plays a role of injecting electrons into a layer (such as the electron injection layer 7 or the organic light emitting layer 5) on the organic light emitting layer 5 side. As the material of the cathode 8, the material used for the anode 2 can be used. However, in order to perform electron injection efficiently, a metal having a low work function is preferable, and tin, magnesium, indium, calcium, A suitable metal such as aluminum or silver or an alloy thereof is used. Specific examples include low work function alloy electrodes such as magnesium-silver alloy, magnesium-indium alloy, and aluminum-lithium alloy.

  The film thickness of the cathode 8 is usually the same as that of the anode 2.

  For the purpose of protecting the cathode made of a low work function metal, it is preferable to further stack a metal layer having a high work function and stable to the atmosphere because the stability of the device is increased. For this purpose, metals such as aluminum, silver, copper, nickel, chromium, gold, platinum are used.

[9] Others Although the organic electroluminescent element having the layer configuration shown in FIG. 1 has been described above, the organic electroluminescent element of the present invention has another configuration without departing from the gist thereof. Also good. For example, as long as the performance is not impaired, an arbitrary layer may be provided between the anode 2 and the cathode 6 in addition to the layers described above, and an arbitrary layer may be omitted. .

  In the present invention, by using the organic compound of the present invention for the hole transport layer 4, the hole injection layer 3, the hole transport layer 4 and the organic light emitting layer 5 are all laminated by a wet film formation method. be able to. This makes it possible to manufacture a large area display.

  EXAMPLES Next, although an Example demonstrates this invention further more concretely, this invention is not limited to description of a following example, unless the summary is exceeded.

[Synthesis example]
The synthesis example of the organic compound of this invention is shown below.

(Synthesis Example 1)
<Synthesis of Target 1>

  Tris (dibenzylideneacetone) dipalladium in a solution of p-anisidine (5.42 g), 4-bromobiphenyl (9.32 g), sodium tert-butoxy (5.38 g), and toluene (80 ml) in a nitrogen stream. (0) A solution prepared by stirring chloroform complex (0.104 g), bis (triphenylphosphino) ferrocene (0.222 g), and toluene (5 ml) at 60 ° C. for 15 minutes under a nitrogen atmosphere, The mixture was stirred for 10 hours under heating to reflux. After allowing to cool, activated clay and toluene (100 ml) were added, and the mixture was stirred for 15 minutes with heating under reflux. After standing to cool, the insoluble material was filtered off, activated clay was added to the filtrate, and the mixture was stirred for 15 minutes while heating under reflux. After allowing to cool, the insoluble material was filtered off and concentrated, and the resulting precipitate was recrystallized from toluene to give the intended product 1 (6.59 g).

<Synthesis of Target 2>

In a nitrogen stream, 4-bromo-4′-methoxybiphenyl (10.0 g), potassium iodide (63.1 g), copper (I) iodide (36.2 g), and dimethylformamide (64 ml) were heated to reflux. The mixture was stirred for 8 hours. The reaction mixture was added to 0.1N hydrochloric acid (360 ml) and stirred, and then the precipitate was filtered off and washed with ethanol. Chloroform (150 ml) was added to the obtained solid content, and the mixture was stirred for 1 hour under reflux with heating to dissolve the soluble components. Then, the solution components were separated by filtration, and the filtrate was concentrated. The obtained solid was purified by recrystallization from methanol to obtain the desired product 2 (9.56 g).

<Synthesis of Target 3>

  In a nitrogen stream, target 1 (5.78 g), target 2 (7.16 g), copper (1.87 g), potassium carbonate (5.80 g), and tetraglyme (15 ml) were heated to 200 ° C. Stir for 10 hours. After allowing to cool, chloroform (200 ml) was added and stirred, and then insoluble matters were filtered off, and the filtrate was concentrated. The obtained solid was suspended and washed with ethanol to obtain Target 3 (7.10 g).

<Synthesis of Target 4>

The target product 3 (6.86 g) and dichloromethane (100 ml) were cooled to 0 ° C. in a nitrogen stream, and a 1M methylene chloride solution of boron tribromide (35 ml) was added dropwise. The mixture was warmed to room temperature and stirred for 2 hours. After adding sodium bicarbonate water, the mixture was extracted with ethyl acetate, the organic layer was concentrated, and purified by silica gel column chromatography (hexane / ethyl acetate = 1/1) to obtain the desired product 4 (3.68 g). By DEI-MS (m / z = 429 (M ⁺ )), it was confirmed to be the target product 4.

<Synthesis of Target 5>

In a nitrogen stream, potassium hydroxide (3.25 g) and dimethyl sulfoxide (100 ml) were stirred at room temperature for 15 minutes, the target compound 4 (5.00 g) was added, and the mixture was stirred at room temperature for 15 minutes. Bromobutoxymethyl) -3-methyloxetane (6.90 g) was added and stirred at room temperature for 8 hours. After adding methylene chloride (200 ml) and water (200 ml) and stirring, the organic layer was dried over magnesium sulfate, concentrated and purified by silica gel chromatography (hexane / ethyl acetate mixture) to obtain the target compound 5 (4.2 g) was obtained.
It was confirmed to be the target product 5 by DEI-MS (m / z = 741 (M ⁺ )).

(Synthesis Example 2)
<Synthesis of Target 6>

  To a solution of 4,4′-diaminodiphenyl ether (6.44 g), 4-bromobiphenyl (15.0 g), sodium tert-butoxy (8.66 g), and toluene (120 ml) in a nitrogen stream was added tris (dibenzylidene). Acetone) dipalladium (0) chloroform complex (0.166 g), bis (triphenylphosphino) ferrocene (0.356 g), and toluene (5 ml) prepared by stirring at 60 ° C. for 15 minutes in a nitrogen atmosphere Was added and stirred for 4 hours under reflux with heating. After allowing to cool, toluene and activated clay were added, and the mixture was stirred for 15 minutes. The insoluble material was filtered off, the filtrate was concentrated, and ethanol was added. The precipitate was collected by filtration and then suspended and washed in the order of ethanol, methanol, toluene, and methanol to obtain the desired product 6 (7.48 g).

<Synthesis of Target 7>

  To a four-necked flask equipped with a DC stirrer, dropping funnel, and condenser, a mixed solution of 50% by weight aqueous sodium hydroxide (300 g) and hexane (250 mL) was added, and tetra n-butylammonium bromide (TBABr) (4. 98 g, 15.5 mmol) was added. After cooling the mixture to 5 ° C., a mixture of methyl oxetane methanol (31 g) and 1,4-dibromobutane (200 g) was added dropwise with vigorous stirring. After completion of dropping, the mixture was stirred for 15 minutes at room temperature, further stirred for 15 minutes under reflux, and stirred for 15 minutes while being allowed to cool to room temperature. The organic layer is separated, the organic layer is washed with water and dried over magnesium sulfate, the solvent is removed under reduced pressure, and 3- (4-bromobutoxymethyl) -3- is obtained by distillation under reduced pressure (0.42 mmHg, 72 ° C.). Methyl oxetane (52.2 g) was obtained.

  In a nitrogen stream, pulverized potassium hydroxide (8.98 g) was added to a solution of dimethyl sulfoxide (50 ml), then m-bromophenol (6.92 g) was added, and the mixture was stirred for 30 minutes, and then 3- (4-bromobutoxy). Methyl) -3-methyloxetane (12.33 g) was added and stirred at room temperature for 6 hours. The precipitate was collected by filtration, extracted with methylene chloride, the oil layer was concentrated, and purified by silica gel chromatography (hexane / methylene chloride mixture) to give the intended product 7 (11.4 g).

<Synthesis of Target 8>

In a nitrogen stream, a solution of target 6 (2.52 g), target 7 (3.95 g), tert-butoxy sodium (1.15 g), and toluene (50 ml) was added to tris (dibenzylideneacetone) dipalladium ( 0) A solution prepared by stirring chloroform complex (0.207 g), tri-tert-butylphosphine (0.243 g), and toluene (20 ml) at 60 ° C. for 15 minutes in a nitrogen atmosphere was added at 80 ° C. Stir for 4 hours. After allowing to cool, methylene chloride (50 ml) was added, and the mixture was stirred for 30 minutes. The insoluble material was filtered off, and the filtrate was concentrated. The product was purified by silica gel chromatography (methylene chloride / ethyl acetate mixture) and treated with activated clay in a toluene solvent to give the intended product 8 (1.74 g).
It was confirmed to be the target product 8 by DEI-MS (m / z = 1000 (M ⁺ )).

(Synthesis Example 3)
<Synthesis of Target 9>

  Under a nitrogen stream, a dehydrated toluene solution (50 mL) of diphenylphosphinoferrocene (166 mg, 0.30 mmol) and trisdibenzylideneacetone dipalladium chloroform adduct (155 mg, 0.15 mmol) was stirred at 30 ° C. for 10 minutes. Bromo-4′-diphenylaminobiphenyl (6.0 g, 14.99 mmol), 4,4′-diaminodiphenyl ether (1.5 g, 7.49 mmol), tert-butoxy sodium (1.73 g, 18 mmol) were added. The temperature was raised to 100 ° C. and stirred for 8 hours. The reaction mixture was poured into water, the organic layer was separated, washed with a saturated aqueous sodium chloride solution, and dried over magnesium sulfate. The solvent was distilled off under reduced pressure, and the residue was subjected to silica gel column chromatography to obtain the intended product 9 (4.24 g).

<Synthesis of Target Product 10>

Under a nitrogen stream, a dehydrated toluene solution (20 mL) of tri-tert-butylphosphine (174 mg, 0.86 mmol) and trisdibenzylideneacetone dipalladium chloroform adduct (148 mg, 0.14 mmol) was stirred at 30 ° C. for 10 minutes, A catalyst was prepared. To this, target product 9 (4.0 g, 4.77 mmol), target product 7 (3.45 g, 10.5 mmol), and sodium tert-butoxy (1.21 g, 12.6 mmol) were added. The temperature was raised to 90 ° C. and stirred for 8 hours. The reaction mixture was poured into water, the organic layer was separated, washed with a saturated aqueous sodium chloride solution, and dried over magnesium sulfate. The solvent was distilled off under reduced pressure, and the residue was subjected to silica gel column chromatography to obtain the desired product 10 (2.47 g%).
It was confirmed to be the target product 10 by DEI-MS (m / z = 1334 (M ⁺ )).

(Synthesis Example 4)
<Synthesis of Target 11>

  3,4'-diphenylaminoether (24.03 g), bromobenzene (37.68 g), and tert-butoxy sodium (25.37 g) and toluene (190 ml) were charged, and the system was sufficiently purged with nitrogen. Warmed to 50 ° C. (Solution A). Bis (triphenylphosphino) ferrocene (1.35 g) was added to a 10 mL toluene solution of tris (dibenzylideneacetone) dipalladium chloroform complex (0.62 g) and heated to 50 ° C. (solution B). In a nitrogen stream, solution B was added to solution A, and heated and reacted at 100 ° C. for 6 and a half hours. After allowing to cool, the filtrate was concentrated by suction filtration. Purification by silica gel column chromatography (hexane / methylene chloride = 1/1) gave the target product 11 (23.60 g).

<Synthesis of Target 12>

  The target product 11 (7.8 g), 1-benzyloxy-3-bromobenzene (12.88 g), sodium tert-butoxy (9.36 g), and toluene (190 mL) were charged, and the system was sufficiently purged with nitrogen. And heated to 60 ° C. (solution C). Tri-tert-butylphosphine (1.1 g) was added to a 15 mL toluene solution of tris (dibenzylideneacetone) dipalladium chloroform complex (0.92 g) and heated to 60 ° C. (solution D). In a nitrogen stream, solution D was added to solution C and heated to reflux for 5 hours. The mixture was allowed to cool to room temperature, filtered through celite, and the filtrate was concentrated. The resulting crude product was purified by silica gel column chromatography (hexane / methylene chloride = 1/1) to obtain the desired product 12 (14.8 g).

<Synthesis of Target Product 13>

  The target product 12 (14.8 g) was dissolved in tetrahydrofuran (100 mL), 5 wt% palladium on carbon (2.20 g) was added, and the inside of the system was replaced with hydrogen. The reduction reaction was performed at 60 ° C. for 7 hours. After completion of the reaction, the system was purged with nitrogen, the catalyst was filtered off, celite was passed through the filtrate, and the filtrate was concentrated. Purification by silica gel column chromatography (hexane / methylene chloride = 1/1) gave the target product 13 (10.00 g).

<Synthesis of Target Product 14>

The target product 13 (3.05 g), 2-chloroethyl vinyl ether (2.42 g), potassium carbonate (3.53 g), and N, N-dimethylformamide (25 mL) were charged, and a small amount of kalim iodide was added. The reaction was conducted by heating at 100 ° C. for 5 hours and further at 100 ° C. for 2.5 hours. After completion of the reaction, water was added to the reaction solution and extracted with ethyl acetate. The obtained organic layer was washed twice with water and further with saturated saline. Sodium sulfate was added to the organic layer, dried and dried, and concentrated. The crude product was purified by silica gel column chromatography (hexane / methylene chloride = 1/1, 2 times hexane / ethyl acetate = 1/1) to obtain the desired product 14 (1.91 g).
By DEI-MS (m / z = 676 (M ⁺ )), it was confirmed to be the target product 14. The glass transition temperature of this product was 9 ° C.

(Synthesis Example 5)
<Synthesis of Target 15>

The target product 13 (13.1 g), 6-bromo-1-hexane (7.42 g), potassium carbonate (11.44 g), and N, N-dimethylformamide (110 mL) were charged and the mixture was charged at 70 ° C. for 7.5 hours. The reaction was heated. Since the target product 13 as a raw material almost disappeared, water was added to the reaction solution and extracted with methylene chloride. The obtained organic layer was washed with water three times and concentrated. The crude product was purified by silica gel column chromatography (hexane / methylene chloride = 1/1) to obtain the intended product 15 (10.80 g).
By DEI-MS (m / z = 700 (M ⁺ )), it was confirmed to be the target product 15. The glass transition temperature of this product was -11 ° C.

(Synthesis Example 6)
<Synthesis of Target 16>

  Under a nitrogen atmosphere, 3-bromophenol (16.9 g), potassium carbonate (53.8 g), N, N-dimethylformamide (97.4 mL), and 1,4-dibromobutane (63.1 g) were added at room temperature. For 5 and a half hours. The reaction mixture was extracted with toluene, and the organic layer was washed with brine, dried over magnesium sulfate, and concentrated under reduced pressure. The residue was distilled (4.8 mmHg / 60 ° C.) to remove 1,4-dibromobutane, and then purified by silica gel column chromatography (hexane / methylene chloride = 3/1) to obtain the target product 16 (9. 7 g) was obtained.

<Synthesis of Target 17>

  Under a nitrogen atmosphere, m-hydroxybenzaldehyde (4.06 g), potassium carbonate (17.5 g), N, N-dimethylformamide (38.5 mL), and target product 16 (9.77 g) were added, and 5 ° C. was added. Stir for half an hour. After cooling to room temperature, the reaction mixture was extracted with toluene, and the organic layer was washed with brine, dried over magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (hexane / methylene chloride = 5/1) to give the intended product 17 (10.3 g).

<Synthesis of Target 18>

  The target product 11 (3 g), target product 17 (5.94 g), cesium carbonate (13.8 g), and toluene (38 mL) were added in a nitrogen stream, and the mixture was stirred at 60 ° C. Tri-tert-butylphosphine (1.1 g) was added to a toluene solution (20 mL) of palladium (II) acetate (0.304 g), and a solution heated to 50 ° C. was added, and the mixture was refluxed for 7 hours. After cooling to room temperature, the reaction mixture was filtered and the filtrate was concentrated under reduced pressure. The residue was purified by silica gel column chromatography (methylene chloride / ethyl acetate = 70/1) to give the intended product 18 (2.99 g).

<Synthesis of Target 19>

In a nitrogen stream, target product 18 (2.52 g), methyltriphenylphosphonium iodide (2.41 g), and dehydrated tetrahydrofuran (50 mL) were added, and the mixture was stirred at 0 ° C. to t-butoxy potassium (0. 67 g) was added, and the mixture was stirred for 4 hours and then stirred at room temperature for 1 hour. While cooling with ice, water was added to the reaction mixture, and the mixture was extracted with ethyl acetate. The organic layer was washed with water, dried over magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (hexane / methylene chloride = 1/2) to give the intended product 19 (1.7 g).
It was confirmed to be the target product 19 by DEI-MS (m / z = 884 (M ⁺ )). This had a glass transition temperature of 73 ° C. and a weight loss starting temperature under a nitrogen stream of 447 ° C.

[Insolubilization test on hole injection layer]
(Reference Example 1)
A glass substrate having a size of 25 mm × 37.5 mm was washed with ultrapure water, dried with dry nitrogen, and subjected to UV / ozone cleaning. A hole transporting polymer of the following structural formula (P1) (homopolymer. Mw = 27,000, Mn = 13,000) and 4 of the following structural formula (B1) at the concentrations described in the following composition preparation conditions. -A composition containing isopropyl-4'-methyldiphenyliodonium tetrakis (pentafluorophenyl) borate (additive: electron-accepting compound) and ethyl benzoate (solvent) was prepared, and the composition was washed on a glass substrate. A film was formed by spin coating.

＜組成物調製条件＞
溶媒：安息香酸エチル
正孔輸送性高分子（Ｐ１）濃度：２重量％
電子受容性化合物（Ｂ１）濃度：０．８０重量％

<Composition preparation conditions>
Solvent: Ethyl benzoate Hole transporting polymer (P1) Concentration: 2% by weight
Electron accepting compound (B1) concentration: 0.80% by weight

  The spin coating was performed in an air atmosphere at a temperature of 23 ° C. and a relative humidity of 60%, the spinner rotation speed was 1500 rpm, and the spinner rotation time was 30 seconds. After the film formation, the film was heated on the hot plate under the following heating conditions in the atmosphere, and then the film was scraped to a width of about 1 mm, and the film thickness L1 (nm) was measured with a film thickness meter (Tencor P-15).

<Heating conditions>
After drying for 1 minute at 80 ° C on a hot plate, heat drying for 180 minutes at 230 ° C in an oven

  Then, this substrate is set on a spinner, and the xylene is dropped on the position where the film thickness is measured, and after 10 seconds, spin processing is performed at a spinner rotation speed of 1500 rpm and a spinner time of 30 seconds. The reduced film thickness L1-L2 (nm) after xylene spin treatment was calculated to evaluate the degree of insolubilization.

  As a result, the film thickness L1 before the xylene spin treatment is 34 nm, and the reduced film thickness L1-L2 after the xylene spin treatment is 2 nm or less. Therefore, the film after coating and drying is insoluble in xylene. Was confirmed.

(Reference Example 2)
The insolubilization degree was evaluated by performing film formation and film thickness measurement in the same manner as in Reference Example 1, except that toluene spin treatment was performed instead of xylene spin treatment after film formation and drying. It was confirmed that the later film was insoluble in toluene.

(Example 1)
On the thin film of the mixture of the hole transporting polymer (P1) and the electron accepting compound (B1) formed in the same manner as in Reference Example 1, the organic compound (H1) of the present invention having the following structure (in Synthesis Example 1) An organic electroluminescent element composition prepared by dissolving the synthesized target compound 5) in xylene (solvent) at a concentration of 2.0% by weight was spin-coated to form a film. The spin coating was performed in an air atmosphere at a temperature of 23 ° C. and a relative humidity of 60%, the spinner rotation speed was 1500 rpm, and the spinner rotation time was 30 seconds. After film formation, heat drying was performed at 130 ° C. for 1 hour under reduced pressure on a hot plate.

About the formed film | membrane, it carried out similarly to the reference example 1, the film thickness before and behind xylene spin processing was measured, and the degree of insolubilization was similarly evaluated.
As a result, the reduction rate (L3) of the film thickness L4 of the hole transport material film after xylene spin treatment with respect to the film thickness L3 of the hole transport material film formed using the organic compound (H1) before xylene spin treatment -L4 / L3) was 1% or less, and it was confirmed that the hole transport material film formed using this organic compound (H1) was insoluble in xylene.

  The film thicknesses L3 and L4 of the hole transport material film were formed by wiping the hole transport material film with a width of about 1 mm with a xylene solvent after film formation of the hole transport material, and the film thickness with a film thickness meter (Tencor P-15). L3 and L4 (nm) were measured and determined.

(Example 2)
The organic electroluminescent element composition containing the organic compound (H1) of the present invention was formed as a spin coat, and then the heating and drying temperature was set to 150 ° C., and the heating and drying atmosphere was changed to the atmosphere. The film and film thickness were measured to evaluate the degree of insolubilization.
As a result, the reduction rate of the film thickness before and after the xylene spin treatment was 2% or less, and it was confirmed that the film formed using the organic compound (H1) was insoluble in xylene.

(Example 3)
The degree of insolubilization was the same as in Example 2 except that the organic compound (H2) of the present invention having the following structure (target compound 8 synthesized in Synthesis Example 1) was used instead of the organic compound (H1). Evaluation was performed.

  As a result, the decrease rate of the film thickness before and after the xylene spin treatment was 1% or less, and it was confirmed that the film formed using the organic compound (H2) was insoluble in xylene.

(Comparative Example 1)
The degree of insolubilization in the same manner as in Example 2 except that 1.5 wt% toluene of the comparative compound (J1) having the following structure was used instead of the 2.0 wt% xylene solution of the organic compound (H1). Was evaluated.

  As a result, the reduction rate of the film thickness before and after the xylene spin treatment was 9% or more, and the film formed using the comparative compound (J1) was not sufficiently insoluble in xylene.

(Reference Example 3)
The degree of insolubilization was evaluated in the same manner as in Comparative Example 1 except that the organic electroluminescent element composition containing the comparative compound (J1) was heated and dried at 200 ° C.
As a result, the reduction rate of the film thickness before and after the xylene spin treatment is 2% or less, and when the heat drying temperature is high, the film formed using the comparative compound (J1) is insoluble in xylene. confirmed.

  Table 1 shows the results of the insolubilization test on the hole injection layer.

  As shown in Table 1, the organic compound of the present invention could be insolubilized under mild conditions as compared with the comparative compound (J1).

[Production of organic electroluminescence device]
Example 4
The organic electroluminescent element shown in FIG. 1 was produced.
An indium tin oxide (ITO) transparent conductive film deposited on a glass substrate 1 with a thickness of 120 nm (manufactured by Sanyo Vacuum Co., Ltd., sputtered film product) using ordinary photolithography technology and hydrochloric acid etching Then, the anode 2 was formed by patterning into stripes having a width of 2 mm. The patterned ITO substrate is cleaned in the order of ultrasonic cleaning with an aqueous surfactant solution, water cleaning with ultrapure water, ultrasonic cleaning with ultrapure water, and water cleaning with ultrapure water, followed by drying with compressed air, and finally UV irradiation. Ozone cleaning was performed.

  First, 2% by weight of a hole transporting polymer having a repeating structure represented by the above structural formula (P1) and 4-isopropyl-4′-methyldiphenyliodonium tetrakis (pentafluorophenyl) borate represented by the structural formula (B1) After 0.8% by weight was dissolved in ethyl benzoate as a solvent, it was filtered using a PTFE (polytetrafluoroethylene) membrane filter having a pore size of 0.2 μm to prepare a coating composition. This coating composition was spin-coated on the glass substrate. The spin coating was performed in an air atmosphere at a temperature of 23 ° C. and a relative humidity of 60%, the spinner rotation speed was 1500 rpm, and the spinner time was 30 seconds. After spin coating, it was heated and dried on a hot plate at 80 ° C. for 1 minute, and then heated in an oven at 230 ° C. for 180 minutes in an atmospheric atmosphere. In this way, a hole injection layer 3 having a thickness of 34 nm was formed.

Subsequently, an organic electroluminescent element composition containing the organic compound (H1) of the present invention was prepared under the conditions shown below, filtered using a 0.2 μm-pore PTFE membrane filter, and spin coated on the hole injection layer 3. did. The spin coating was performed in a nitrogen atmosphere glove box, the spinner rotation speed was 1500 rpm, and the spinner time was 30 seconds.
<Composition preparation conditions>
Solvent: Xylene Concentration of organic compound (H1) of the present invention: 0.80% by weight

After spin coating, heat drying was performed under the following conditions. In this way, a hole transport layer 4 having a film thickness of 18 nm was formed.
<Heat drying conditions>
Atmosphere: Under reduced pressure (vacuum degree 0.01 MPa)
Heating temperature: 130 ° C
Heating time: 1 hour

  Next, 20 mg of a compound represented by the following structural formula (C-1), 20 mg of a compound represented by the following structural formula (C-2), and 2 mg of a compound represented by the following structural formula (C-3) Then, it was dissolved in 2.0 g of xylene to prepare a light emitting layer solution. This light emitting layer solution was applied on the hole transporting layer 4 by spin coating to a thickness of 40 nm to form the light emitting layer 5. Spin coating was performed in a nitrogen atmosphere glove box, the spinner rotation speed was 1500 rpm, and the spinner time was 30 seconds. After the application, it was dried by heating at a vacuum of 0.01 MPa and 130 ° C. for 1 hour.

Next, the substrate on which the hole injection layer 3, the hole transport layer 4 and the light emitting layer 5 are coated is carried into a multi-chamber vacuum deposition apparatus connected to a glove box without being exposed to the atmosphere, and an oil rotary pump After roughly evacuating the apparatus by the above, the apparatus is evacuated using a cryopump until the degree of vacuum in the apparatus becomes 3.8 × 10 ⁻⁵ Pa, and the compound represented by the following structural formula (C-4) is evacuated. The hole blocking layer 6 was obtained by laminating by vapor deposition. The degree of vacuum during deposition is 2.8 × 10 ^{−5 to} 3.6 × 10 ⁻⁵ Pa, the deposition rate is controlled in the range of 0.8 to 1.2 liters / second, and a film with a thickness of 5 nm The hole blocking layer 6 was formed by laminating on the top.

Next, deposition was performed by heating tris (8-hydroxyquinolinato) aluminum placed in a ceramic crucible disposed in the apparatus. The degree of vacuum during deposition is 2.7 × 10 ^{−5 to} 3.4 × 10 ⁻⁵ Pa, the deposition rate is controlled within the range of 0.8 to 1.2 liters / second, and a hole with a thickness of 30 nm is blocked An electron transport layer 7 was formed by laminating on the layer 6.

Here, the element that has been vapor-deposited up to the electron transport layer 7 is transported in vacuum from the organic layer vapor-deposition chamber on which the electron-transport layer is vapor-deposited to a metal vapor deposition chamber, and is used as a mask for cathode vapor deposition in a 2 mm wide stripe shape. The shadow mask is placed in close contact with the element so as to be orthogonal to the ITO stripe of the anode 2 and installed in another vacuum deposition apparatus, and the degree of vacuum in the apparatus is 6.3 × 10 6 as in the organic layer deposition. ^It exhausted until it became ^-5 Pa or less.

First, lithium fluoride (LiF) is used as the cathode 8 at a deposition rate of 0.09 to 0.15 liters / second and a degree of vacuum of 4.1 × 10 ^{−5 to} 7.8 × 10 ⁻⁵ Pa using a molybdenum boat. Controlled, a film was formed on the electron transport layer with a film thickness of 0.5 nm. Next, aluminum was similarly heated by a molybdenum boat, and the deposition rate was controlled to 0.6 to 7.0 liters / second and the degree of vacuum 2.4 × 10 ^{−5 to} 12 × 10 ⁻⁵ Pa, and the film thickness was 80 nm. A cathode 8 was formed by forming an aluminum layer. The substrate temperature at the time of vapor deposition of the above two-layer cathode was kept at room temperature.

Subsequently, in order to prevent the element from being deteriorated by moisture in the atmosphere during storage, a sealing process was performed by the method described below.
In a nitrogen glove box connected to a vacuum deposition apparatus, a photocurable resin (30Y-437 manufactured by ThreeBond Co., Ltd.) is applied to the outer periphery of a 23 mm × 23 mm size glass plate with a width of about 1 mm, and is applied to the center. A moisture getter sheet (manufactured by Dynic Co., Ltd.) was installed. On this, the board | substrate which complete | finished cathode formation was bonded together so that the vapor-deposited surface might oppose a desiccant sheet. Thereafter, only the region where the photocurable resin was applied was irradiated with ultraviolet light to cure the resin.
As described above, an organic electroluminescent element having a light emitting area portion having a size of 2 mm × 2 mm was obtained.
Table 2 shows the light emission characteristics of the obtained organic electroluminescent device.
In addition, Table 3 shows the results of a drive life test performed on the obtained organic electroluminescent element under the following conditions.

<Driving conditions>
Temperature Room temperature Drive method DC drive (DC drive)
Initial luminance 2,500 cd / m ²

(Example 5)
Using the organic compound (H2) of the present invention instead of the organic compound (H1), an organic electroluminescent element composition for forming the hole transport layer 4 was prepared as follows, and after spin coating, under the following conditions: An organic electroluminescent device was prepared in the same manner as in Example 4 except that a 19 nm-thick hole transport layer was formed by heating and drying. Similarly, evaluation of light emission characteristics and driving life test were performed, and the results are shown. 2 and shown in Table 3.
<Composition preparation conditions>
Solvent: Xylene Concentration of organic compound (H2) of the present invention: 0.90% by weight
<Heat drying conditions>
Atmosphere: Nitrogen Heating temperature: 150 ° C
Heating time: 1 hour

(Comparative Example 2)
A comparative compound (J1) is used in place of the organic compound (H1), an organic electroluminescent element composition for forming the hole transport layer 4 is prepared as follows, spin-coated, and then heated and dried under the following conditions. An organic electroluminescence device was prepared in the same manner as in Example 4 except that a 21 nm-thick hole transport layer was formed. The emission characteristics were evaluated and the drive life test was conducted in the same manner. It was shown in 3.
<Composition preparation conditions>
Solvent: Toluene Comparative compound (J1) Concentration: 0.5% by weight
<Heat drying conditions>
Atmosphere: Nitrogen Heating temperature: 200 ° C
Heating time: 1 hour

  As shown in Tables 2 and 3, it was clear that by using the organic compounds (H1) and (H2) of the present invention, a high-luminance and high-efficiency device was obtained, and that the lifetime of the device was extended. It is.

  The present invention relates to various fields in which organic electroluminescent elements are used, for example, light sources (for example, light sources of copiers, flat panel displays (for example, for OA computers and wall-mounted televisions) and surface light emitters). It can be suitably used in the fields of liquid crystal displays and backlights of instruments), display panels, indicator lamps and the like.

It is sectional drawing which shows typically an example of the structure of the organic electroluminescent element of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate 2 Anode 3 Hole injection layer 4 Hole transport layer 5 Organic light emitting layer 6 Hole blocking layer 7 Electron injection layer 8 Cathode

Claims (12)

An organic compound represented by the following formula (I).

[In formula (I), n represents 0, 1 or 2.
T ¹ and T ² each independently represent a crosslinking group.
G ^{1 to} G ³ are each independently formed by linking 1 to 30 groups selected from the group consisting of a phenylene group, —O— group, —C (═O) — group, and —CH ₂ — group. Represents a valent group. In addition, the phenylene group and the —CH ₂ — group may have a substituent. However, G ¹ and G ² are each independently a group containing at least one —CH ₂ — group.
A ¹ and A ² each independently represent a divalent group represented by the following formula (I-1).

(In the formula (I-1), m represents 0 or 1.
Ar ^{1 to} Ar ⁵ each independently represents an aromatic hydrocarbon group which may have a substituent or an aromatic heterocyclic group which may have a substituent. However, in the formula (I-1) in ^{A 1,} Ar ¹ and Ar ² are not the same. Further, when a plurality of Ar ^{1 to} Ar ⁵ are present in one molecule, Ar ^{1 to} Ar ⁵ may be the same or different. )
When n = 2, the two G ³ and A ² may be the same or different. ]   The organic compound according to claim 1, wherein n is 0 in the formula (I). In the above formula (I), n is 1 or 2, ^{G 3} is -O- group, an organic compound according to claim 1.   The organic compound according to any one of claims 1 to 3, wherein m is 0 in the formula (I-1). 5. The organic compound according to claim 1, wherein, in the formula (I), T ¹ and T ² are each independently a crosslinking group selected from the following crosslinking group group T. 6.
<Crosslinking group T>

(In formula, R < ¹ > -R < ⁵ > represents a hydrogen atom or an alkyl group each independently.
Ar ¹¹ represents an aromatic hydrocarbon group which may have a substituent or an aromatic heterocyclic group which may have a substituent. )   The organic electroluminescent element material which consists of an organic compound of any one of Claim 1 thru | or 5.   The composition for organic electroluminescent elements containing the organic compound of any one of Claim 1 thru | or 5.   A polymer compound obtained by polymerizing the organic compound according to claim 1.   6. An organic electroluminescence device having an anode, a cathode, and one or more organic layers sandwiched between the anode and the cathode on a substrate, wherein at least one of the organic layers is the one according to claim 1-5. The organic electroluminescent element containing the organic compound of any one, and / or the high molecular compound of Claim 8.   The organic electroluminescent element according to claim 9, wherein the layer containing the organic compound and / or polymer compound is a hole transport layer.   The organic electroluminescent element according to claim 10, further comprising a light emitting layer on the hole transport layer.   The organic layer has a hole injection layer, a hole transport layer, and a light emitting layer, and all of the hole injection layer, the hole transport layer, and the light emitting layer are formed by a wet film forming method. The organic electroluminescent element of any one of Claims 1.

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