JP2017119793A - Copolymer, organic electroluminescent element material, composition for the production of organic electroluminescent element and organic electroluminescent element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a novel and improved copolymer which can improve the emission lifetime of an organic EL element, an organic electroluminescent element material comprising the copolymer, a composition for the production of an organic electroluminescent element, and an organic electroluminescent element prepared with the material.SOLUTION: The present invention provides a copolymer comprising a unit having a fluorene structure or an azafluorene structure represented by a specific general structural formula, and a unit having a carbazole structure or an azacarbazole structure represented by a specific general structural formula.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a copolymer, an organic electroluminescence element material, a composition for producing an organic electroluminescence element, and an organic electroluminescence element.

  In recent years, display devices and lighting devices using organic electroluminescence elements (organic EL elements) which are self-luminous light emitting elements have been actively developed.

  In such an organic EL element, in order to manufacture a large-area element at a lower cost (cost), it is considered to use a solution coating method instead of the vacuum deposition method. Compared with the vacuum deposition method, the solution coating method has a higher material utilization efficiency, can easily form a large area, and does not require an expensive vacuum device. It is expected as a device manufacturing method.

  As materials for organic EL elements used for the solution coating method, for example, low molecular weight materials and high molecular weight materials have been studied. Among these, high molecular weight materials are particularly developed because of high coating uniformity and easy lamination. In particular, development of a polymer-based hole transport material that can be used in displays and lighting devices is desired.

  For example, the following Patent Documents 1 to 10 disclose organic EL device materials in which a part of a low-molecular material is substituted with a vinyl group and polymerized by polymerization.

JP-A-7-90255 JP-A-8-54833 JP-A-8-269133 JP 2001-098023 A JP 2002-110359 A JP 2003-313240 A JP 2004-059743 A Japanese Patent Laid-Open No. 2006-237592 JP 2008-198989 A JP 2008-218983 A

  However, the organic EL element manufactured by the solution coating method using the organic EL element material disclosed in Patent Documents 1 to 10 has a problem that the light emission lifetime is not sufficient.

  Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to provide a novel and improved copolymer capable of improving the light emission lifetime of an organic EL device, An object of the present invention is to provide an organic electroluminescence device material containing a copolymer, a composition for producing an organic electroluminescence device, and an organic electroluminescence device using the material.

上記式中、
Ｒ^１〜Ｒ^７は、水素原子、重水素原子、ハロゲン（ｈａｌｏｇｅｎ）原子、ヒドロキシ（ｈｙｄｒｏｘｙ）基、アミノ（ａｍｉｎｏ）基、ニトロ（ｎｉｔｒｏ）基、シアノ（ｃｙａｎｏ）基、置換もしくは無置換のシリル（ｓｉｌｙｌ）基、置換もしくは無置換の炭素数１〜２０のアルキル（ａｌｋｙｌ）基、置換もしくは無置換の環形成炭素数３〜１６のシクロアルキル（ｃｙｃｌｏａｌｋｙｌ）基、置換もしくは無置換の環形成炭素数６〜３０のアリール（ａｒｙｌ）基、置換もしくは無置換の炭素数１〜２０のアルコキシ（ａｌｋｏｘｙ）基、置換もしくは無置換の環形成炭素数３〜１６のシクロアルコキシ（ｃｙｃｌｏａｌｋｏｘｙ）基、置換もしくは無置換の環形成炭素数６〜３０のアリールオキシ（ａｒｙｌｏｘｙ）基、置換もしくは無置換の炭素数７〜４０のアラルキル（ａｒａｌｋｙｌ）基、置換もしくは無置換の環形成炭素数５〜３０のヘテロアリール（ｈｅｔｅｒｏａｒｙｌ）基、置換もしくは無置換の炭素数１〜２０のアルキルアミノ（ａｌｋｙｌａｍｉｎｏ）基、置換もしくは無置換の環形成炭素数６〜３０のアリールアミノ（ａｒｙｌａｍｉｎｏ）基であり、
Ｌ^１およびＬ^２は、互いに独立して、単結合、置換もしくは無置換の炭素数１〜１０のアルキレン（ａｌｋｙｌｅｎｅ）基、置換もしくは無置換の炭素数５〜３０のシクロアルキレン（ｃｙｃｌｏａｌｋｙｌｅｎｅ）基、置換もしくは無置換の環形成炭素数６〜３０のアリーレン（ａｒｙｌｅｎｅ）基、環形成原子数６〜３０のヘテロアリーレン（ｈｅｔｅｒｏａｒｙｌｅｎｅ）基または置換もしくは無置換のアミノ基であり、
Ｃｚは、カルバゾール（ｃａｒｂａｚｏｌｅ）構造またはアザカルバゾール（ａｚａｃａｒｂａｚｏｌｅ）構造を有する基であり、
Ｍは、−（Ａ−Ｂ）_ｎ−Ａ_ｍ−または−（Ｂ−Ａ）_ｎ−Ｂ_ｍ−で表される基であり、
ここで、
ｎは、１〜２０の整数であり、
ｍは、０または１であり、
ｐは、１〜１０の整数であり、
Ａは、フルオレン（ｆｌｕｏｒｅｎｅ）構造またはアザフルオレン（ａｚａｆｌｕｏｒｅｎｅ）構造を有する基であり、
Ｂは、一般式（３）で表される基であり、

上記一般式（３）中、
Ｌ^３およびＬ^４は、互いに独立して、単結合、置換もしくは無置換の炭素数１〜２０のアルキレン基、置換もしくは無置換の環形成炭素数３〜１６のシクロアルキレン基、置換もしくは無置換の環形成炭素数６〜３０のアリーレン基、置換もしくは無置換の炭素数１〜２０のオキシアルキレン（ｏｘｙａｌｋｙｌｅｎｅ）基、置換もしくは無置換の環形成炭素数３〜１６のオキシシクロアルキレン（ｏｘｙｃｙｃｌｏａｌｋｙｌｅｎｅ）基、置換もしくは無置換の環形成炭素数６〜３０のオキシアリーレン（ｏｘｙａｒｙｌｅｎｅ）基、置換もしくは無置換の炭素数７〜４０のアラルキレン（ａｒａｌｋｙｌｅｎｅ）基、置換もしくは無置換の環形成炭素数５〜３０のヘテロアリーレン基、置換もしくは無置換の炭素数１〜２０のアミノアルキレン（ａｍｉｎｏａｌｋｙｌｅｎｅ）基、置換もしくは無置換の環形成炭素数６〜３０のアミノアリーレン（ａｍｉｎｏａｒｙｌｅｎｅ）基、またはアルキル基もしくはアリール基で置換されたシリレン（ｓｉｌｙｌｅｎｅ）基であり、
Ｒ^８は、水素原子、置換もしくは無置換の炭素数１〜２０のアルキル基、置換もしくは無置換の環形成炭素数３〜１６のシクロアルキル基、置換もしくは無置換の環形成炭素数６〜３０のアリール基、置換もしくは無置換の炭素数１〜２０のアルコキシ基、置換もしくは無置換の環形成炭素数３〜１６のシクロアルコキシ基、置換もしくは無置換の環形成炭素数６〜３０のアリールオキシ基、置換もしくは無置換の炭素数７〜４０のアラルキル基、置換もしくは無置換の環形成炭素数５〜３０のヘテロアリール基、置換もしくは無置換の炭素数１〜２０のアルキルアミノ基、置換もしくは無置換の環形成炭素数６〜３０のアリールアミノ基、またはこれらの基と前記Ｌ_３もしくは前記Ｌ_４とが結合して形成された環状基であり、
＊は、他の基との結合部位である。 In order to solve the above problems, according to an aspect of the present invention, there is provided a copolymer including a unit represented by the following general formula (1) and a unit represented by the following general formula (2). The

In the above formula,
R ^{1 to} R ⁷ are each a hydrogen atom, a deuterium atom, a halogen atom, a hydroxy group, an amino group, a nitro group, a cyano group, a substituted or unsubstituted silyl group. (Silyl) group, substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl group having 3 to 16 ring carbon atoms, substituted or unsubstituted ring forming carbon atom An aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkoxy group having 3 to 16 ring carbon atoms, substituted, or Unsubstituted aryloxy group having 6 to 30 ring carbon atoms, substituted Or an unsubstituted aralkyl group having 7 to 40 carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 30 ring carbon atoms, or a substituted or unsubstituted alkylamino group having 1 to 20 carbon atoms. An (alkylamino) group, a substituted or unsubstituted arylamino group having 6 to 30 ring carbon atoms,
L ¹ and L ² are each independently a single bond, a substituted or unsubstituted alkylene group having 1 to 10 carbon atoms, a substituted or unsubstituted cycloalkylene group having 5 to 30 carbon atoms, A substituted or unsubstituted arylene group having 6 to 30 ring carbon atoms, a heteroarylene group having 6 to 30 ring atoms, or a substituted or unsubstituted amino group,
Cz is a group having a carbazole structure or an azacarbazole structure;
M is a group represented by-(AB) _n -A _m -or-(BA) _n -B _m- ;
here,
n is an integer of 1 to 20,
m is 0 or 1,
p is an integer of 1 to 10,
A is a group having a fluorene structure or an azafluorene structure;
B is a group represented by the general formula (3),

In the general formula (3),
L ³ and L ⁴ each independently represent a single bond, a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkylene group having 3 to 16 ring carbon atoms, substituted or unsubstituted. An arylene group having 6 to 30 ring carbon atoms, a substituted or unsubstituted oxyalkylene group having 1 to 20 carbon atoms, and a substituted or unsubstituted oxycycloalkylene group having 3 to 16 ring carbon atoms. Substituted or unsubstituted oxyarylene groups having 6 to 30 ring carbon atoms, substituted or unsubstituted aralkylene groups having 7 to 40 carbon atoms, substituted or unsubstituted ring carbon atoms having 5 to 30 carbon atoms A heteroarylene group, a substituted or unsubstituted amino group having 1 to 20 carbon atoms Killen (aminoalkylene) group, a substituted or unsubstituted ring forming amino arylene having from 6 to 30 carbon atoms (aminoarylene) group or a silylene substituted with an alkyl group or aryl group, (silylene) group,
R ⁸ represents a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 16 ring carbon atoms, or a substituted or unsubstituted ring carbon number 6 to 30. Aryl group, substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkoxy group having 3 to 16 ring carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 ring carbon atoms Group, substituted or unsubstituted aralkyl group having 7 to 40 carbon atoms, substituted or unsubstituted heteroaryl group having 5 to 30 ring carbon atoms, substituted or unsubstituted alkylamino group having 1 to 20 carbon atoms, substituted or An unsubstituted arylamino group having 6 to 30 carbon atoms, or a cyclic group formed by combining these groups with the L ₃ or the L ₄ ;
* Represents a binding site with another group.

  According to this viewpoint, it is possible to improve the light emission lifetime of the organic EL element.

上記一般式（４）において、
Ｒ^９〜Ｒ^１２は、互いに独立して、水素原子、ハロゲン原子、ヒドロキシ基、アミノ基、ニトロ基、シアノ基、置換もしくは無置換のシリル基、置換もしくは無置換の炭素数１〜２０のアルキル基、置換もしくは無置換の環形成炭素数３〜１６のシクロアルキル基、置換もしくは無置換の環形成炭素数６〜３０のアリール基、置換もしくは無置換の炭素数１〜２０のアルコキシ基、置換もしくは無置換の環形成炭素数３〜１６のシクロアルコキシ基、置換もしくは無置換の環形成炭素数６〜３０のアリールオキシ基、置換もしくは無置換の炭素数７〜４０のアラルキル基、置換もしくは無置換の環形成炭素数５〜３０のヘテロアリール基、置換もしくは無置換の炭素数１〜２０のアルキルアミノ基、置換もしくは無置換の環形成炭素数６〜３０のアリールアミノ基、置換もしくは無置換の環形成炭素数６〜３０のアリールスルホキシ（ａｒｙｌｓｕｌｆｏｘｙ）基または隣接したこれらの基が互いに結合して形成された環状基であり、
ａおよびｂは、互いに独立して、１〜４の整数であり、
Ｘ^１〜Ｘ^８は、互いに独立して、メチン（ｍｅｔｈｉｎｅ）基または窒素原子である。 Said A is group represented by following General formula (4), and may couple | bond with another group in any substitution position.

In the general formula (4),
R ^{9 to} R ¹² are each independently a hydrogen atom, a halogen atom, a hydroxy group, an amino group, a nitro group, a cyano group, a substituted or unsubstituted silyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms. Group, substituted or unsubstituted cycloalkyl group having 3 to 16 ring carbon atoms, substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, substituted Or an unsubstituted cycloalkoxy group having 3 to 16 ring carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 30 ring carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 40 carbon atoms, substituted or unsubstituted Substituted heteroaryl group having 5 to 30 ring carbon atoms, substituted or unsubstituted alkylamino group having 1 to 20 carbon atoms, substituted or unsubstituted ring carbon atoms having 6 to 20 carbon atoms 0 arylamino group, a substituted or unsubstituted ring formed C6-30 aryl sulfoxide (arylsulfoxy) group or adjacent cyclic group these groups are bonded to each other to form,
a and b are each independently an integer of 1 to 4,
X ^{1 to} X ⁸ are each independently a methine group or a nitrogen atom.

  According to this viewpoint, it is possible to further improve the light emission lifetime of the organic EL element.

X ^{1 to} X ⁸ have a methine group,
R ⁹ and R ¹⁰ may be independently of each other a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms.

  According to this viewpoint, it is possible to further improve the light emission lifetime of the organic EL element.

L ¹ represents a single bond, a substituted or unsubstituted cycloalkylene group having 5 to 30 carbon atoms, a substituted or unsubstituted arylene group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted ring atom having 6 to 30 ring atoms. Or a heteroarylene group of

  According to this viewpoint, it is possible to further improve the light emission lifetime of the organic EL element.

上記式中
Ｙ^１〜Ｙ^８は、互いに独立して、窒素原子またはメチン基であり、
Ｒ^１３〜Ｒ^１５は、互いに独立して、水素原子、ハロゲン原子、ヒドロキシ基、アミノ基、ニトロ基、シアノ基、置換もしくは無置換のシリル基、置換もしくは無置換の炭素数１〜２０のアルキル基、置換もしくは無置換の炭素数１〜２０のアミノアルキル基、置換もしくは無置換の環形成炭素数３〜１６のシクロアルキル基、置換もしくは無置換の環形成炭素数６〜３０のアリール基、置換もしくは無置換の環形成炭素数６〜３０のアミノアリール基、置換もしくは無置換の環形成炭素数５〜３０のヘテロアリール基、置換もしくは無置換の炭素数１〜２０のアルコキシ基、置換もしくは無置換の環形成炭素数３〜１６のシクロアルコキシ基、置換もしくは無置換の環形成炭素数６〜３０のアリールオキシ基、置換もしくは無置換の炭素数７〜４０のアラルキル基、置換もしくは無置換の炭素数１〜２０のアルキルアミノ基、置換もしくは無置換の環形成炭素数６〜３０のアリールアミノ基、または隣接したこれらの基が互いに結合して形成された環状基、あるいは他の基との結合であり、
ｃ、ｄは、互いに独立して、０〜４の整数である。 The Cz may be a group represented by the following general formula (5) or a group in which a plurality of groups represented by the general formula (5) are connected.

In the above formula, Y ^{1 to} Y ⁸ are each independently a nitrogen atom or a methine group,
R ^{13 to} R ¹⁵ are each independently a hydrogen atom, a halogen atom, a hydroxy group, an amino group, a nitro group, a cyano group, a substituted or unsubstituted silyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms. Group, substituted or unsubstituted aminoalkyl group having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl group having 3 to 16 ring carbon atoms, substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, A substituted or unsubstituted aminoaryl group having 6 to 30 ring carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 30 ring carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, substituted or Unsubstituted cycloalkoxy group having 3 to 16 ring carbon atoms, substituted or unsubstituted aryloxy group having 6 to 30 ring carbon atoms, substituted or unsubstituted carbon A 7 to 40 aralkyl group, a substituted or unsubstituted alkylamino group having 1 to 20 carbon atoms, a substituted or unsubstituted arylamino group having 6 to 30 ring carbon atoms, or adjacent groups bonded to each other; A formed cyclic group, or a bond with another group,
c and d are each independently an integer of 0 to 4.

式中、＊は、他の基との結合部位である。 The Cz may be a group represented by the following general formula (6) or (7) or a group in which a plurality of groups represented by the general formula (6) or (7) are connected.

In the formula, * is a binding site with another group.

  According to this viewpoint, it is possible to further improve the light emission lifetime of the organic EL element.

上記の架橋基群において、
Ｒ^１５〜Ｒ^２１は、水素原子、または置換もしくは無置換の炭素数１〜１０のアルキル基であり、
ｐは、１〜１０の整数である。 Furthermore, a polymerizable comonomer having at least one cross-linking group selected from the following cross-linking group group may be included as a polymerization unit.

In the above crosslinking group group,
R ^{15 to} R ²¹ are a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms,
p is an integer of 1-10.

  According to this viewpoint, it is possible to further improve the light emission lifetime of the organic EL element.

上記一般式（８）において、
Ｒ^２２〜Ｒ^２４は、互いに独立して、水素原子、置換もしくは無置換の炭素数１〜１０のアルキル基、または置換もしくは無置換の環形成炭素数６〜３０のアリール基であり、
Ｒ^２５〜Ｒ^２９は、互いに独立して、水素原子、ハロゲン原子、ヒドロキシ基、アミノ基、ニトロ基、シアノ基、置換もしくは無置換のシリル基、置換もしくは無置換の炭素数１〜２０のアルキル基、置換もしくは無置換の環形成炭素数３〜１６のシクロアルキル基、置換もしくは無置換の環形成炭素数６〜３０のアリール基、置換もしくは無置換の炭素数１〜２０のアルコキシ基、置換もしくは無置換の環形成炭素数３〜１６のシクロアルコキシ基、置換もしくは無置換の環形成炭素数６〜３０のアリールオキシ基、置換もしくは無置換の炭素数７〜４０のアラルキル基、置換もしくは無置換の環形成炭素数５〜３０のヘテロアリール基、置換もしくは無置換の炭素数１〜２０のアルキルアミノ基、置換もしくは無置換の環形成炭素数６〜３０のアリールアミノ基、または隣接したこれらの基が互いに結合して形成された環状基であり、
Ｌ^５は、単結合、置換もしくは無置換の炭素数１〜２０のアルキレン基、置換もしくは無置換の環形成炭素数３〜１６のシクロアルキレン基、置換もしくは無置換の環形成炭素数６〜３０のアリーレン基、置換もしくは無置換の炭素数１〜２０のオキシアルキレン基、置換もしくは無置換の環形成炭素数３〜１６のオキシシクロアルキレン基、置換もしくは無置換の環形成炭素数６〜３０のオキシアリーレン基、置換もしくは無置換の炭素数７〜４０のアラルキレン基、置換もしくは無置換の環形成炭素数５〜３０のヘテロアリーレン基、置換もしくは無置換の炭素数１〜２０のアミノアルキレン基、置換もしくは無置換の環形成炭素数６〜３０のアミノアリーレン基、またはアルキル基もしくはアリール基で置換されたシリレン基であり、
前記Ｒ^２５〜Ｒ^２９のうち、少なくとも１つ以上は、前記架橋基群から選択された架橋基である。 The polymerizable comonomer may be a compound represented by the following general formula (8).

In the general formula (8),
R ^{22 to} R ²⁴ are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms,
R ^{25 to} R ²⁹ are each independently a hydrogen atom, a halogen atom, a hydroxy group, an amino group, a nitro group, a cyano group, a substituted or unsubstituted silyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms. Group, substituted or unsubstituted cycloalkyl group having 3 to 16 ring carbon atoms, substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, substituted Or an unsubstituted cycloalkoxy group having 3 to 16 ring carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 30 ring carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 40 carbon atoms, substituted or unsubstituted Substituted heteroaryl group having 5 to 30 ring carbon atoms, substituted or unsubstituted alkylamino group having 1 to 20 carbon atoms, substituted or unsubstituted ring carbon number 6 30 arylamino group or an adjacent cyclic group these groups are bonded to each other to form,
L ⁵ is a single bond, a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkylene group having 3 to 16 ring carbon atoms, a substituted or unsubstituted ring forming carbon atom having 6 to 30 carbon atoms. An arylene group, a substituted or unsubstituted oxyalkylene group having 1 to 20 carbon atoms, a substituted or unsubstituted oxycycloalkylene group having 3 to 16 ring carbon atoms, a substituted or unsubstituted ring forming carbon atom having 6 to 30 carbon atoms An oxyarylene group, a substituted or unsubstituted aralkylene group having 7 to 40 carbon atoms, a substituted or unsubstituted heteroarylene group having 5 to 30 ring carbon atoms, a substituted or unsubstituted aminoalkylene group having 1 to 20 carbon atoms, A substituted or unsubstituted aminoarylene group having 6 to 30 ring carbon atoms, or a silylene group substituted with an alkyl group or an aryl group,
At least one of R ^{25 to} R ²⁹ is a crosslinking group selected from the group of crosslinking groups.

  According to this viewpoint, it is possible to further improve the light emission lifetime of the organic EL element.

上記一般式（９）において、
Ａ’は、前記一般式（３）で表される基であり、
Ｂ’は、フルオレン構造またはアザフルオレン構造を有する基であり、
ｒは、１〜２０の整数であり、
＊は、フルオレニレン基との結合部位である。 The L ⁵ may be a group represented by the following general formula (9).

In the general formula (9),
A ′ is a group represented by the general formula (3),
B ′ is a group having a fluorene structure or an azafluorene structure;
r is an integer of 1 to 20,
* Is a binding site with a fluorenylene group.

The L ⁵ may be a group represented by the general formula (3).

    According to this viewpoint, it is possible to further improve the light emission lifetime of the organic EL element.

In order to solve the above problem, according to another aspect of the present invention, a pair of electrodes,
And at least one organic layer disposed between the pair of electrodes,
There is provided an organic electroluminescence device in which at least one of the organic layers contains the copolymer described above.

  According to this viewpoint, it is possible to improve the light emission lifetime of the organic EL element.

  At least one layer of the organic layer may be a hole transport layer containing the copolymer.

  According to this viewpoint, it is possible to further improve the light emission lifetime of the organic EL element.

  At least one of the organic layers may be a light emitting layer containing a light emitting material capable of emitting light from triplet excitons.

  According to this viewpoint, it is possible to improve the light emission efficiency and the light emission lifetime of the organic EL element.

  Moreover, in order to solve the said subject, according to another viewpoint of this invention, the organic electroluminescent element material containing the said copolymer is provided.

  According to this viewpoint, it is possible to improve the light emission efficiency and the light emission lifetime of the organic EL element.

  Moreover, in order to solve the said subject, according to another viewpoint of this invention, the composition for organic electroluminescent element manufacture containing the said copolymer and a liquid medium is provided.

  According to this aspect, it is possible to provide a composition suitable for the solution coating method and improve the light emission lifetime of the organic EL element.

  As described above, according to the present invention, it is possible to improve the light emission lifetime of the organic EL element.

It is a schematic diagram which shows an example of the organic EL element which concerns on one Embodiment of this invention.

  Exemplary embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In addition, in this specification and drawing, about the component which has the substantially same function structure, duplication description is abbreviate | omitted by attaching | subjecting the same code | symbol.

<1. Copolymer>
First, the copolymer according to this embodiment will be described.
The copolymer according to this embodiment includes a unit represented by the following general formula (1) (hereinafter also referred to as “aminofluorene unit”) and a unit represented by the following general formula (2) (hereinafter referred to as “aminofluorene unit”). , Also referred to as “carbazole unit”).

In the above formula,
R ^{1 to} R ⁷ are a hydrogen atom, deuterium atom, halogen atom, hydroxy group, amino group, nitro group, cyano group, substituted or unsubstituted silyl group, substituted or unsubstituted alkyl group having 1 to 20 carbon atoms. Substituted or unsubstituted cycloalkyl group having 3 to 16 ring carbon atoms, substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, substituted or Unsubstituted cycloalkoxy group having 3 to 16 carbon atoms, substituted or unsubstituted aryloxy group having 6 to 30 ring carbon atoms, substituted or unsubstituted aralkyl group having 7 to 40 carbon atoms, substituted or unsubstituted A heteroaryl group having 5 to 30 ring carbon atoms, a substituted or unsubstituted alkylamino group having 1 to 20 carbon atoms, a substituted or unsubstituted ring structure having 6 to 30 carbon atoms An arylamino group,
L ¹ and L ² are each independently a single bond, a substituted or unsubstituted alkylene group having 1 to 10 carbon atoms, a substituted or unsubstituted cycloalkylene group having 5 to 30 carbon atoms, a substituted or unsubstituted ring. An arylene group having 6 to 30 carbon atoms, a heteroarylene group having 6 to 30 ring atoms, or a substituted or unsubstituted amino group,
Cz is a group having a carbazole structure or an azacarbazole structure;
M is a group represented by-(AB) _n -A _m -or-(BA) _n -B _m- ;
here,
n is an integer of 1 to 20,
m is 0 or 1,
p is an integer of 1 to 10,
A is a group having a fluorene structure or an azafluorene structure,
B is a group represented by the general formula (3),

In the general formula (3),
L ³ and L ⁴ each independently represent a single bond, a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkylene group having 3 to 16 ring carbon atoms, substituted or unsubstituted. An arylene group having 6 to 30 ring carbon atoms, a substituted or unsubstituted oxyalkylene group having 1 to 20 carbon atoms, a substituted or unsubstituted oxycycloalkylene group having 3 to 16 ring carbon atoms, a substituted or unsubstituted group. Oxyarylene group having 6 to 30 ring carbon atoms, substituted or unsubstituted aralkylene group having 7 to 40 carbon atoms, substituted or unsubstituted heteroarylene group having 5 to 30 ring carbon atoms, substituted or unsubstituted carbon number An aminoalkylene group having 1 to 20 amino acids, a substituted or unsubstituted aminoarylene group having 6 to 30 ring carbon atoms, an alkyl group or an aryl group; A conversion has been silylene group,
R ⁸ represents a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 16 ring carbon atoms, or a substituted or unsubstituted ring carbon number 6 to 30. Aryl group, substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkoxy group having 3 to 16 ring carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 ring carbon atoms Group, substituted or unsubstituted aralkyl group having 7 to 40 carbon atoms, substituted or unsubstituted heteroaryl group having 5 to 30 ring carbon atoms, substituted or unsubstituted alkylamino group having 1 to 20 carbon atoms, substituted or An unsubstituted arylamino group having 6 to 30 carbon atoms or a cyclic group formed by combining these groups with L ₃ or L ₄ ;
* Represents a binding site with another group.

  Thereby, the light emission lifetime of the organic EL element containing the said copolymer can be improved. More specifically, in the copolymer, the carbazole unit contributes to improvement of the glass transition point of the copolymer. Therefore, the above-described copolymer has a relatively high glass transition temperature and excellent thermal stability. Therefore, the organic EL element configured to contain the copolymer is relatively stable against driving heat. And as a result of suppressing deterioration and deformation | transformation by the drive heat of an organic EL element, the light emission lifetime of the organic EL element containing the said copolymer can be lengthened compared with the conventional organic EL element.

  Further, as described above, the copolymer has a relatively high glass transition temperature, and is hardly deteriorated or deformed by heat when the solvent is removed after film formation. Moreover, when forming another layer after film-forming with the said copolymer, the said copolymer with a comparatively high glass transition temperature is comparatively hard to melt | dissolve in a solvent. In the solution coating method, it is suitable for forming a laminated film. As described above, the copolymer can be suitably applied to a solution coating method. In addition, the organic layer formed by the solution coating method using the copolymer as a material has no thickness unevenness and is uniform. Further, the organic layer has a smooth surface. Therefore, in the organic EL element manufactured using the above-mentioned copolymer as a material by a solution coating method, uneven application of driving voltage and uneven light emission are suppressed.

  Further, when the bond dissociation energy (energy) between carbons of a vinyl polymer in a cation radical state is calculated, fluorenyl (polymer) has a fluorenyl group at the polymerization site rather than a vinyl polymer having a phenyl group at the polymerization site. A vinyl polymer having a fluorenyl group has a carbon-bond dissociation energy about three times higher. As a result, the above copolymer having a fluorenyl group at the polymerization site is chemically stable, and therefore, the light emission lifetime of the organic EL device containing the copolymer is improved.

The copolymer has excellent hole transporting ability and hole injecting ability. Therefore, it can be suitably used as a hole transport material, a hole injection material, and a host material of a light emitting layer.
Hereinafter, it demonstrates in detail for every unit of the said copolymer.

(Aminofluorene unit)
Hereinafter, the aminofluorene unit represented by the general formula (1) will be described.

As described above, R ^{1 to} R ⁴ of the aminofluorene unit are independently of each other hydrogen atom, deuterium atom, halogen atom, hydroxy group, amino group, nitro group, cyano group, substituted or unsubstituted silyl group. Substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl group having 3 to 16 ring carbon atoms, substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, substituted or An unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkoxy group having 3 to 16 ring carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 30 ring carbon atoms, substituted or unsubstituted An aralkyl group having 7 to 40 carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 30 ring carbon atoms, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms. Amino group, a substituted or unsubstituted ring forming an arylamino group having 6 to 30 carbon atoms. In the present specification, “hydrogen atom” is a concept including “deuterium atom” even when there is no special description about “deuterium atom” and exists in each group. The hydrogen atom can optionally be a deuterium atom.

  The alkyl group can be a linear or branched alkyl group. The linear or branched alkyl group is not particularly limited, and examples thereof include a methyl group, an ethyl group, a propyl group, a butyl group, an octyl group, a decyl group. decyl) group, linear alkyl group such as pentadecyl group, and branched alkyl group such as t-butyl group. The number of carbon atoms of the linear or branched alkyl group is preferably 1 to 15, more preferably 1 to 10, and more preferably 2 to 9. The number of carbon atoms of the cyclic alkyl group is not particularly limited, but is preferably 3 to 12, more preferably 3 to 10, and further preferably 4 to 7.

  Examples of the cycloalkyl group include a monocyclic hydrocarbon group such as a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a bicycloalkyl group, and a tricycloalkyl group. Examples thereof include a bridged cyclic hydrocarbon group.

  Examples of the aryl group include a monocyclic aromatic group such as a phenyl group, a biphenyl group, a terphenyl group, a quaterphenyl group, a quinquephenyl group, Non-condensed polycyclic aromatic groups such as sexiphenyl group, fluoranthenyl group, triphenylenyl group, naphthyl group, anthryl group, phenanthryl group, phenanthryl group fluorenyl group, indenyl group, pyrenyl group, acetonaphten l) such as condensed polycyclic aromatic group such as a group can be exemplified. The number of ring-forming carbon atoms of the aryl group is preferably 6-18, more preferably 6-12.

  Examples of the heteroaryl group include a pyrrolyl group, an imidazolyl group, a pyrazolyl group, an oxazolyl group, an isoxazolyl group, an oxadiazolyl group, and an oxadiazolyl group. Furanyl group, pyranyl group, thienyl group, pyridyl group, pyrazyl group, pyrimidinyl group, pyridazinyl group, triazinyl group, triazinyl group, triazinyl group monocyclic groups such as quinolyl and isoquinolyl groups. Loaryl group, benzo (pyridyl) furanyl group, benzofuranyl group, benzothienyl group, indolyl group, carbazolyl group, carbolinyl group, phenanthridinyl group (phenanthridinyl group) , An acridinyl group, a perimidinyl group, a phenanthrolinyl group, a benzoxazolyl group, a benzothiazolyl group, a quinoxalyl group, and a quinoxalyl group. (Pyrazol l) group, and dibenzofuranyl (dibenzofuranyl) groups, and polycyclic heteroaryl groups such as dibenzothienyl (dibenzothienyl) group. The number of ring-forming atoms of the heteroaryl group is preferably 3-24, more preferably 5-12.

Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
Examples of the alkoxy group, the cycloalkoxy group, and the aryloxy group include groups in which an oxygen atom is inserted into the bonding site with the above-described alkyl group or other group of the cycloalkoxy group.
Furthermore, examples of the alkylamino group and arylamino group include amino groups in which the alkyl group and aryl group described above are substituted with 1, 2, or 3 substituents.
Examples of the aralkyl group include groups in which the above-described alkyl group is substituted with one or more aryl groups described above.

  Substituents that can be substituted for the above-described groups such as an aryl group and an alkyl group are not particularly limited, and examples thereof include a cyano group, a silyl group, and mono-mono having 1 to 10 carbon atoms. ), Di (di-) or trialkylsilyl group, straight chain, branched or cyclic alkyl group having 1 to 10 carbon atoms, straight chain having 1 to 10 carbon atoms Alternatively, a branched alkoxy group, an aryl group having 6 to 15 ring carbon atoms, an aryloxy group having 6 to 15 ring carbon atoms, an arylcarbonyl group having 6 to 15 ring carbon atoms ( arylcarbonyl group, heterocyclyl group having 3 to 32 ring carbon atoms, and 1 to 10 carbon atoms. Roh (mono-) or di (di-) such as an alkylamino group and cyclization mono (mono-) or di (di-) arylamino group having a carbon number of 6 to 15 and the like. Unless otherwise stated, when “substituted” is simply described, it can be substituted with the above substituent.

R ^{1 to} R ³ are preferably a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, and more preferably a hydrogen atom or an unsubstituted alkyl group having 1 to 5 carbon atoms. More preferably, it is a hydrogen atom.

R ⁴ is preferably a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 16 ring carbon atoms, or a substituted or unsubstituted ring. It is an aryl group having 6 to 30 carbon atoms formed.

R ⁴ is more preferably a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, and further preferably a hydrogen atom or an unsubstituted alkyl group having 1 to 5 carbon atoms.

L ¹ is a group as described above.
Examples of the alkylene group include linear or branched alkylene groups having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms, and more preferably 1 to 3 carbon atoms. Examples of the alkylene group include a methylene group, an ethylene group, an n-propylene group, an n-butylene group, and the like.

  Examples of the arylene group include a phenylene group, a biphenylene group, a terphenylene group, a naphthylene group, etc. The arylene group may have 6 to 30 ring carbon atoms. However, it is preferably 6 to 24, more preferably 6 to 12.

  Examples of the cycloalkylene group include a monocyclic group such as a cyclopropylene group, a cyclobutylene group, a cyclopentylene group, a cyclohexylene group, and a decahydronaphthalenediphthalyl group. And a polycyclic group such as bicycloundecane diyl, a bridged ring hydrocarbon group such as a bicycloalkylene group, a tricycloalkylene group, and the like. The ring-forming carbon number of the cycloalkylene group may be 5-30, but is preferably 5-24, more preferably 5-12.

  Examples of the heteroarylene group include a pyrrole diyl group, a thiophene diyl group, a furan diyl group, a pyrazole diyl group, an imidazoldiyl group, and an oxazole diyl group. oxazole diyl group, isoxazole diyl group, oxadiazole diyl group, triazole diyl group, thiadiazole diyl group, isothiol diyl group, isothiol diyl group, isothiol diyl group A 5-membered aromatic heterocyclic group of pyridinediyl yl) group, pyridazine diyl group, pyrimidine diyl group, pyrazine diyl group and the like 6-membered aromatic heterocyclic ring, indole diyl group, isoindole diyl group Group, benzothiophene diyl group, isobenzothiophene diyl group, benzofuran diyl group, isobenzofuran diyl group, indazole diol group, indazole diol group benzimidazole diyl) group Imidazopyridine diyl (imidazopyridine diyl) group, benzothiazole-diyl (benzothiazole diyl) group, quinolinediyl (quinoline diyl) group, and bicyclic aromatic heterocyclic groups such as isoquinoline-diyl (isoquinoline diyl) group. Although the ring-forming carbon number of a heteroarylene group should just be 5-30, Preferably it is 5-24, More preferably, it is 5-12.

Among the above, L ¹ is a single bond, a substituted or unsubstituted cycloalkylene group having 5 to 30 carbon atoms, a substituted or unsubstituted arylene group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted ring forming atom. It is preferably a heteroarylene group of several 6 to 30, more preferably a single bond, a substituted or unsubstituted arylene group or a cycloalkylene group, and further preferably a single bond or an unsubstituted arylene group. A single bond, a phenylene group or a naphthylene group is even more preferable.

As described above, M is a group represented by-(AB) _n -A _m -or-(BA) _n -B _m- .

In M, A is a group having a fluorene structure or an azafluorene structure.
A can be, for example, a group represented by the following general formula (4). When A is a compound represented by the following general formula (4), it can be bonded to another group at any substitution position.

In the general formula (4),
R ^{9 to} R ¹² are each independently a hydrogen atom, a halogen atom, a hydroxy group, an amino group, a nitro group, a cyano group, a substituted or unsubstituted silyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms. Group, substituted or unsubstituted cycloalkyl group having 3 to 16 ring carbon atoms, substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, substituted Or an unsubstituted cycloalkoxy group having 3 to 16 ring carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 30 ring carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 40 carbon atoms, substituted or unsubstituted Substituted heteroaryl group having 5 to 30 ring carbon atoms, substituted or unsubstituted alkylamino group having 1 to 20 carbon atoms, substituted or unsubstituted ring carbon atoms having 6 to 20 carbon atoms 0 arylamino group, a substituted or unsubstituted ring formed C6-30 aryl sulfoxide group or adjacent cyclic group these groups are bonded to each other to form,
a and b are each independently an integer of 1 to 4,
X ^{1 to} X ⁸ are each independently a methine group or a nitrogen atom.

R ⁹ and R ¹⁰ are not particularly limited as long as they are the groups described above, but are a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms. It is preferably a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, more preferably a hydrogen atom or an unsubstituted linear alkyl group having 1 to 20 carbon atoms. preferable. As the alkyl group and aryl group in this case, for example, it includes the same groups as R ¹ to R ⁴ described above.

R ¹¹ and R ¹² are not particularly limited as long as they are the groups described above, but are a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms. Alternatively, it is preferably a substituted or unsubstituted heteroaryl group having 5 to 30 ring carbon atoms, more preferably a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a hydrogen atom or carbon More preferably, it is a linear alkyl group having a number of 1 to 20. As the alkyl group and aryl group in this case, for example, it includes the same groups as R ¹ to R ⁴ described above.

When R ¹¹ and R ¹² are an aryl group or a heteroaryl group, they may be condensed with the fluorene structure or azafluorene structure in the general formula (4) to form a condensed ring.

Further, X ¹ to X ⁴ is preferably but one 0 or one of them is a nitrogen atom, and more preferably are all methine groups. In X ^{5 to} X ⁸ , 0 or 1 of these is preferably a nitrogen atom, and more preferably all are methine groups.

Further, a is equal to or less than the number of methine groups respectively in ^X 1 to X ^4. Similarly, b is equal to or less than the number of methine groups in X ^{5 to} X ⁸ , respectively.

Specific examples of the group represented by the general formula (4) are shown below.

As described above, B is a group represented by the following general formula (3).

In general formula (4), L ³ and L ⁴ may be groups as described above, but are preferably a single bond or a substituted or unsubstituted arylene group having 6 to 30 ring carbon atoms, More preferred are a single bond, a phenylene group, a bilenifene group, and a naphthylene group, and even more preferred is a single bond or a phenylene group.

In addition, it is preferable that one of L ³ and L ⁴ is a single bond and the other is a substituted or unsubstituted arylene group having 6 to 30 ring carbon atoms.

R ⁸ may be a group as described above, but is preferably a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms. More preferably, it is a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, and more preferably an alkyl group-substituted aryl group having 6 to 12 ring carbon atoms. As the alkyl group and aryl group in this case, for example, it includes the same groups as R ¹ to R ⁴ described above.

  In particular, the aryl group having 6 to 12 ring carbon atoms substituted with an alkyl group is preferably a methylphenyl group or an ethylphenyl group.

  Moreover, in the said General formula (4), n should just be an integer of 1-20, Preferably, it is 1-10, More preferably, it is 1-5, More preferably, it is 1 or 2 is there.

  Specific examples of the aminofluorene unit represented by the general formula (1) described above are shown below. However, the present invention is not limited to these structures.

(Carbazole unit)
Next, the carbazole unit represented by the general formula (2) will be described.

In the above formula, specific groups and preferred groups of R ^{5 to} R ^{7 can be} the same as the specific groups and preferred groups of R ^{1 to} R ⁴ described above.

Further, the carbazole unit of the general formula (2) has a chain group in which p L ² and Cz are alternately polymerized. The specific group for L ² can be the same as the specific group for L ¹ described above. Among the above, L ² represents a single bond, a substituted or unsubstituted cycloalkylene group having 5 to 30 carbon atoms, a substituted or unsubstituted arylene group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted ring forming atom. It is preferably a heteroarylene group of several 6-30, more preferably a single bond, a substituted or unsubstituted arylene group, more preferably a single bond or a substituted or unsubstituted arylene group, Or a substituted or unsubstituted phenylene group or fluorenediyl group.

  Cz is a group having a carbazole structure or an azacarbazole structure. For example, Cz may be a group in which Cz is a group represented by the following general formula (5) or a plurality of groups represented by the general formula (5).

In the above formula, Y ^{1 to} Y ⁸ are each independently a nitrogen atom or a methine group,
R ^{13 to} R ¹⁵ are each independently a hydrogen atom, a halogen atom, a hydroxy group, an amino group, a nitro group, a cyano group, a substituted or unsubstituted silyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms. Group, substituted or unsubstituted aminoalkyl group having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl group having 3 to 16 ring carbon atoms, substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, A substituted or unsubstituted aminoaryl group having 6 to 30 ring carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 30 ring carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, substituted or Unsubstituted cycloalkoxy group having 3 to 16 ring carbon atoms, substituted or unsubstituted aryloxy group having 6 to 30 ring carbon atoms, substituted or unsubstituted carbon A 7 to 40 aralkyl group, a substituted or unsubstituted alkylamino group having 1 to 20 carbon atoms, a substituted or unsubstituted arylamino group having 6 to 30 ring carbon atoms, or adjacent groups bonded to each other; A formed cyclic group, or a bond with another group,
c and d are each independently an integer of 0 to 4.

Y ^{1 to} Y ⁴ may be in the above-described range, but 0 or 1 of these is preferably a nitrogen atom, and more preferably all are methine groups. In Y ^{5 to} Y ⁸ , 0 or 1 of these is preferably a nitrogen atom, and more preferably all are methine groups.

Further, a is equal to or less than the number of methine groups respectively in ^Y 1 to Y ^4. Similarly, b is equal to or less than the number of methine groups in Y ^{5 to} Y ⁸ , respectively.

  Cz is preferably a group represented by the following general formula (6) or (7) or a group in which a plurality of groups represented by the general formula (6) or (7) are connected.

R ^{13 to} R ¹⁵ may be any of the groups described above, but are preferably a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms. Group, substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms or substituted or unsubstituted aminoaryl group having 6 to 30 ring carbon atoms, more preferably a hydrogen atom, substituted or unsubstituted carbon atom 1 Or a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, and more preferably a hydrogen atom, an unsubstituted linear alkyl group having 1 to 15 carbon atoms, or a substituted or unsubstituted group. A phenyl group or a fluorenyl group.

Also, if R ¹³ or R ¹⁴ is present in plurality adjacent plurality of R ¹³ or R ¹⁴ also form a fused ring with the carbazole skeleton represented by the general formula (5) (or aza carbazole skeleton) Good. Such cyclic groups include indolocarbazole rings.

Moreover, when R < ¹³ > -R < ¹⁵ > is an unsubstituted C1-C15 linear alkyl group, it is more preferable that carbon number is 1-12.

  Moreover, although p is an integer of 1-10 as mentioned above, Preferably, it is 1-5, More preferably, it is an integer of 1 or 2.

  Specific examples of the carbazole unit represented by the general formula (2) described above are shown below. However, the present invention is not limited to these structures.

(Other units)
The copolymer which concerns on this embodiment may have units other than the unit mentioned above.
For example, a polymerizable comonomer having at least one crosslinking group selected from the following crosslinking group group may be included as a polymerization unit.

In the above crosslinking group group,
R ^{15 to} R ²¹ are a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms,
p is an integer of 1-10.

  Such a polymerizable comonomer can be, for example, a compound represented by the following general formula (8).

In the general formula (8),
R ^{22 to} R ²⁴ are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms,
R ^{25 to} R ²⁹ are each independently a hydrogen atom, a halogen atom, a hydroxy group, an amino group, a nitro group, a cyano group, a substituted or unsubstituted silyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms. Group, substituted or unsubstituted cycloalkyl group having 3 to 16 ring carbon atoms, substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, substituted Or an unsubstituted cycloalkoxy group having 3 to 16 ring carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 30 ring carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 40 carbon atoms, substituted or unsubstituted Substituted heteroaryl group having 5 to 30 ring carbon atoms, substituted or unsubstituted alkylamino group having 1 to 20 carbon atoms, substituted or unsubstituted ring carbon number 6 30 arylamino group or an adjacent cyclic group these groups are bonded to each other to form,
L ⁵ is a single bond, a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkylene group having 3 to 16 ring carbon atoms, a substituted or unsubstituted ring forming carbon atom having 6 to 30 carbon atoms. An arylene group, a substituted or unsubstituted oxyalkylene group having 1 to 20 carbon atoms, a substituted or unsubstituted oxycycloalkylene group having 3 to 16 ring carbon atoms, a substituted or unsubstituted ring forming carbon atom having 6 to 30 carbon atoms An oxyarylene group, a substituted or unsubstituted aralkylene group having 7 to 40 carbon atoms, a substituted or unsubstituted heteroarylene group having 5 to 30 ring carbon atoms, a substituted or unsubstituted aminoalkylene group having 1 to 20 carbon atoms, A substituted or unsubstituted aminoarylene group having 6 to 30 ring carbon atoms, or a silylene group substituted with an alkyl group or an aryl group,
At least one of R ^{25 to} R ²⁹ is a crosslinking group selected from the group of crosslinking groups.

Specific examples and preferred groups of R ^{15 to} R ²⁹ described above can be the same as those of R ^{1 to} R ⁴ described above.
L ⁵ can be, for example, a group represented by the following general formula (9).

In the general formula (9),
A ′ is a group represented by the general formula (3),
B ′ is a group having a fluorene structure or an azafluorene structure;
r is an integer of 1 to 20,
* Is a binding site with a fluorenylene group.

L ⁵ may be a group represented by the general formula (3).
Here, specific examples of structural units (repeating units) corresponding to the polymerizable copolymer having at least one crosslinking group are shown below. However, the constitutional unit corresponding to the polymerizable copolymer having at least one crosslinking group is not limited to the structures exemplified below. In the following, m and n are integers of 1 to 10, for example.

  The specific example of the combination of each unit of the copolymer which concerns on this embodiment demonstrated above is shown. However, the copolymer is not limited to these.

  The polymerization mode of the copolymer is not particularly limited, and can be, for example, random copolymerization, alternating copolymerization, or block copolymerization.

  In addition, the number average molecular weight of the copolymer which concerns on this embodiment is not specifically limited, For example, they are 10,000 or more and 100,000 or less.

  According to the copolymer according to this embodiment as described above, it is possible to improve the light emission lifetime of the organic EL element. In addition, since the copolymer according to this embodiment can be further improved in coating film stability by being formed as a copolymer with a polymerizable comonomer having a crosslinking group, the organic EL device has a laminated structure. The emission characteristics and stability when formed in this manner can be improved.

  The copolymer according to this embodiment can be synthesized by using a known organic synthesis method. For example, the copolymer according to this embodiment can be easily produced using a radical polymerization method. A specific method for synthesizing the copolymer according to this embodiment can be easily understood by those skilled in the art with reference to the examples described later.

<2. Organic Electroluminescence Element Material (Organic EL Element Material)>
The organic EL element material according to this embodiment includes the above-described copolymer. The copolymer can be applied as an organic EL element material. Further, the copolymer has a hole transport ability and a hole injection ability. Therefore, the organic EL element material can be used as a material for a hole transport layer, a hole injection layer, and a light emitting layer, for example.

  In addition, when the organic EL element material is a material of the light emitting layer, the above-described copolymer can be a host material. In this case, the organic EL element material may further include a compound having a hole transporting ability.

  The compound having such hole transporting ability is not particularly limited, and examples thereof include known hole injecting materials, hole transporting materials, and host materials described later.

  When the organic EL element material is a material for the light emitting layer, the organic EL element material may contain a light emitting material. Examples of such a material include a light emitting material described later.

<3. Composition for Manufacturing Organic Electroluminescence Device>
The composition for manufacturing an organic electroluminescence element according to this embodiment is used for forming each layer of an organic EL element by a solution coating method, for example.

  The composition for manufacturing an organic electroluminescence element according to this embodiment includes a compound represented by the general formula (1) and a liquid medium. Usually, the composition for manufacturing an organic electroluminescence device according to the present embodiment includes the above-described organic EL device material and a liquid medium.

  Although it does not specifically limit as a liquid medium, It is preferable that the organic EL element material mentioned above can be melt | dissolved. That is, the composition for producing an organic electroluminescence device is preferably a solution composition.

  Such a liquid medium is not particularly limited, and examples thereof include toluene, xylene, ethylbenzene, diethylbenzene, mesitylene, propylbenzene, and cyclohexylbenzene (propylene). cyclohexylbenzene, dimethoxybenzene, anisole, ethoxytoluene, phenoxytoluene, isopropylbiphenyl, dimethyl anisole henyl acetate), phenyl propionic acid (phenyl propionate), methyl benzoate (methyl benzoate), an aromatic solvent such as ethyl benzoate (ethyl benzoate).

<4. Organic EL device>
Then, with reference to FIG. 1, the organic EL element which concerns on this embodiment is demonstrated in detail. FIG. 1 is a schematic view showing an example of an organic EL element according to this embodiment.

  As shown in FIG. 1, the organic EL device 100 according to this embodiment includes a substrate 110, a first electrode 120 disposed on the substrate 110, a hole injection layer 130 disposed on the first electrode 120, and , A hole transport layer 140 disposed on the hole injection layer 130, a light emitting layer 150 disposed on the hole transport layer 140, an electron transport layer 160 disposed on the light emitting layer 150, and an electron transport layer The electron injection layer 170 disposed on the electrode 160 and the second electrode 180 disposed on the electron injection layer 170 are provided.

  Here, the copolymer according to the present embodiment is included in, for example, any organic layer disposed between the first electrode 120 and the second electrode 180. Specifically, the copolymer according to this embodiment is preferably included in the hole transport layer 140 as a hole transport material. The copolymer according to this embodiment may be contained in the light emitting layer 150 as a host material and in the hole injection layer 130 as a hole injection material.

  Moreover, the organic layer containing the copolymer according to the present embodiment is formed by a solution coating method. Specifically, the organic layer including the copolymer according to the present embodiment is formed by a spin coat method, a casting method, a micro gravure coat method, or a gravure coat method. A bar coat method, a roll coat method, a wire bar coat method, a dip coat method, a spray coat method, a screen printing method, The film is formed using a solution coating method such as a flexographic printing method, an offset printing method, or an ink jet printing method. In addition, as long as the solvent used for the solution coating method can dissolve the copolymer according to the present embodiment, any solvent can be used.

  In addition, it does not specifically limit about the film-forming method of layers other than the organic layer containing the copolymer which concerns on this embodiment. Layers other than the organic layer containing the copolymer according to the present embodiment may be formed by, for example, a vacuum deposition method or a solution coating method.

  As the substrate 110, a substrate used in a general organic EL element can be used. For example, the substrate 110 may be a semiconductor substrate such as a glass substrate or a silicon substrate, or a transparent plastic substrate.

  A first electrode 120 is formed on the substrate 110. Specifically, the first electrode 120 is an anode, and is formed of a metal, an alloy, a conductive compound, or the like having a high work function. For example, the first electrode 120 is transmissive by indium tin oxide (In 2 O 3 -SnO 2: ITO), indium zinc oxide (In 2 O 3 -ZnO), tin oxide (SnO 2), zinc oxide (ZnO), etc., which are excellent in transparency and conductivity. It may be formed as an electrode. The first electrode 120 may be formed as a reflective electrode by stacking magnesium (Mg), aluminum (Al), or the like on the transparent conductive film.

  A hole injection layer 130 is formed on the first electrode 120. The hole injection layer 130 is a layer that facilitates injection of holes from the first electrode 120, and specifically has a thickness of about 10 nm to about 1000 nm, more specifically about 10 nm to about 100 nm. May be formed.

  The hole injection layer 130 can be formed of a known hole injection material. Known hole injection materials for forming the hole injection layer 130 include, for example, triphenylamine-containing polyether ketone (poly (ether ketone) -conting triphenylamine: TCAPEK), 4-isopropyl-4′-methyldiphenyliodonium tetrakis. (Pentafluorophenyl) borate (4-isopropyl-4′-methyldiphenylondium tetrakis (pentafluorophenyl) borate (PPBI)), N, N′-diphenyl-N, N′-bis- [4- (phenyl-m-tolyl-amino) -Phenyl] -biphenyl-4,4′-diamine (N, N′-diphenyl-N, N′-bis- [4- (phenyl-m-tolyl-a ino) -phenyl] -biphenyl-4,4′-diamin: DNTPD), copper phthalocyanine, 4,4 ′, 4 ″ -tris (3-methylphenylphenylamino) triphenylamine (4,4 ′) , 4 "-tris (3-methylphenylphenyl) triphenylamine: m-MTDATA), N, N'-di (1-naphthyl) -N, N'-diphenylbenzidine (N, N'-di (1-naphthyl) -N , N′-diphenylbenzidine: NPB), 4,4 ′, 4 ″ -tris (diphenylamino) triphenylamine (4,4 ′, 4 ″ -tris (diphenylamino) triphenylamine: TDAT A), 4,4 ′, 4 ″ -tris (N, N-2-naphthylphenylamino) triphenylamine (4,4 ′, 4 ″ -tris (N, N-2-naphthylphenylamino) triphenylamine: 2-TNATA ), Polyaniline / dodecylbenzenesulfonic acid, poly (3,4-ethylenedioxythiophene) / poly (4-styrenesulfonate) / poly (4-styreneenesulfone) / poly (4-styrenesulfonate) ), And polyaniline / 10-camphorsulphonic acid Can do.

  A hole transport layer 140 is formed on the hole injection layer 130. The hole transport layer 140 is a layer having a function of transporting holes, and may be formed with a thickness of about 10 nm to about 150 nm, for example. The hole transport layer 140 is preferably formed by a solution coating method using the copolymer according to the present embodiment. According to this method, a copolymer capable of improving the light emission lifetime of the organic EL element 100 can be efficiently formed in a large area.

  However, when any other organic layer of the organic EL element 100 includes the copolymer according to the present embodiment, the hole transport layer 140 may be formed of a known hole transport material. Not too long. Known hole transport materials include, for example, 1,1-bis [(di-4-tolylamino) phenyl] cyclohexane (1,1-bis [(di-4-tolylamino) phenyl] cyclohexane: TAPC), N— Carbazole derivatives such as phenylcarbazole (N-phenylcarbazole) and polyvinylcarbazole, N, N′-bis (3-methylphenyl) -N, N′-diphenyl- [1,1-biphenyl] -4 , 4'-diamine (N, N'-bis (3-methylphenyl) -N, N'-diphenyl- [1,1-biphenyl] -4,4'-diamine: TPD), 4,4 ', 4 " -Tris (N-carbazolyl Triphenylamine (4,4 ′, 4 ″ -tris (N-carbazolyl) triphenylamine: TCTA), as well as N, N′-di (1-naphthyl) -N, N′-diphenylbenzidine (N, N′-di (1-naphthyl) -N, N′-diphenylbenzidine: NPB).

  A light emitting layer 150 is formed on the hole transport layer 140. The light emitting layer 150 is a layer that emits light by fluorescence, phosphorescence, or the like, and is formed using a vacuum deposition method, a spin coating method, an ink jet method, or the like. The light emitting layer 150 may be formed with a thickness of about 10 nm to about 60 nm, for example. As the light emitting material of the light emitting layer 150, a known light emitting material can be used. However, the light-emitting material included in the light-emitting layer 150 is preferably a light-emitting material capable of emitting light from triplet excitons (that is, phosphorescent light emission). In such a case, the light emission lifetime of the organic EL element 100 can be further improved.

  The light-emitting layer 150 is formed using, for example, tris (8-quinolinato) aluminum (Alq3), 4,4′-bis (carbazol-9-yl) biphenyl (4,4′-) as a host material. bis (carbazol-9-yl) biphenyl: CBP), poly (n-vinylcarbazole) (PVK), 9,10-di (naphthalen-2-yl) anthracene (9,10-) di (naphthalene) anthracene (ADN), 4,4 ′, 4 ″ -tris (N-carbazolyl) triphenylamine (4,4 ′, 4 ″ -tris (N-carbazolyl) triphenylamine: TCTA), 1,3, 5-Tris ( -Phenylbenzimidazol-2-yl) benzene (1,3,5-tris (N-phenyl-benzimidazol-2-yl) benzene: TPBI), 3-tert-butyl-9,10-di (naphth-2-) Yl) anthracene (3-tert-butyl-9,10-di (naphth-2-yl) anthracene: TBADN), distyrylarylene (DSA), 4,4′-bis (9-carbazole) -2, 2'-dimethyl-biphenyl (4,4'-bis (9-carbazole) 2,2'-dimethyl-biphenyl: dmCBP) may be included.

  In addition, the light emitting layer 150 includes, for example, perylene and its derivatives, rubrene and its derivatives, coumarin and its derivatives, 4-dicyanomethylene-2- (p-dimethylaminostyryl) as a dopant material. ) -6-methyl-4H-pyran (4-dicyaminomethyl-2- (p-dimethylaminostyryl) -6-methyl-4H-pyran: DCM) and its derivatives, bis [2- (4,6-difluorophenyl) pyridinate] Picolinate iridium (III) (bis [2- (4,6-difluorophenyl) pyridine] picolinate iridium (III): FIrpic), bis (1-phenyl) Soquinoline) (acetylacetonate) iridium (III) (bis (1-phenylisoquinoline) (acetylacetonate) iridium (III): Ir (piq) 2 (acac)), tris (2-phenylpyridine) iridium (III) (tris ( An iridium (Ir) complex such as 2-phenylpyridine) iridium (III): Ir (ppy) 3), an osmium (Os) complex, a platinum complex, or the like may be included.

  An electron transport layer 160 is formed on the light emitting layer 150. The electron transport layer 160 is a layer having a function of transporting electrons, and is formed using a vacuum deposition method, a spin coating method, an ink jet method, or the like. The electron transport layer 160 may be formed with a thickness of about 15 nm to about 50 nm, for example.

  The electron transport layer 160 may be formed of a known electron transport material. Examples of known electron transporting materials include tris (8-quinolinolato) aluminum (Alq3) and compounds having a nitrogen-containing aromatic ring. Specific examples of the compound having a nitrogen-containing aromatic ring include, for example, 1,3,5-tri [(3-pyridyl) -phen-3-yl] benzene (1,3,5-tri [(3-pyrylyl) Compounds containing a pyridine ring, such as -phen-3-yl] benzene), 2,4,6-tris (3 '-(pyridin-3-yl) biphenyl-3-yl) -1,3, Compounds containing a triazine ring such as 5-triazine (2,4,6-tris (3 ′-(pyridin-3-yl) biphenyl-3-yl) -1,3,5-triazine), 2 -(4- (N-phenylbenzoinazolyl-1-yl-phenyl) -9,10-dinaphthylanthracene (2- (4- (N-phenylbenzoimidazo) yl-1-yl-phenyl) -9,10-dinaphthylanthracene imidazole (imidazole) as) can be exemplified compounds comprising a ring.

  An electron injection layer 170 is formed on the electron transport layer 160. The electron injection layer 170 is a layer having a function of facilitating injection of electrons from the second electrode 180, and is formed using a vacuum deposition method or the like. The electron injection layer 170 may be formed with a thickness of about 0.3 nm to about 9 nm. As the electron injection layer 170, any material known as a material for forming the electron injection layer 170 can be used. For example, the electron injection layer 170 may be formed using lithium compounds such as (8-quinolinato) lithium (Liq) and lithium fluoride (LiF), sodium chloride (NaCl), cesium fluoride (CsF). ), Lithium oxide (Li 2 O), barium oxide (BaO), or the like.

  A second electrode 180 is formed on the electron injection layer 170. Specifically, the second electrode 180 is a cathode and is formed of a metal, an alloy, a conductive compound, or the like having a low work function. For example, the second electrode 180 may be a metal such as lithium (Li), magnesium (Mg), aluminum (Al), calcium (Ca), or aluminum-lithium (Al-Li), magnesium-indium (Mg-In), The reflective electrode may be formed of an alloy such as magnesium-silver (Mg-Ag). The second electrode 180 may be formed as a transmissive electrode by a thin film of 20 nm or less of the above metal material, a transparent conductive film such as indium tin oxide (In2O3-SnO2) and indium zinc oxide (In2O3-ZnO). .

  Heretofore, an example of the organic EL element 100 according to the present embodiment has been described. The organic EL element 100 according to this embodiment can further improve the light emission lifetime by having an organic layer containing a copolymer.

  Note that the stacked structure of the organic EL element 100 according to this embodiment is not limited to the above example. The organic EL element 100 according to the present embodiment may be formed with another known laminated structure. For example, in the organic EL element 100, one or more of the hole injection layer 130, the hole transport layer 140, the electron transport layer 160, and the electron injection layer 170 may be omitted, and other layers may be added in addition. You may have. In addition, each layer of the organic EL element 100 may be formed as a single layer or a plurality of layers.

  For example, the organic EL element 100 further includes a hole blocking layer between the hole transport layer 140 and the light emitting layer 150 in order to prevent excitons or holes from diffusing into the electron transport layer 160. Also good. Note that the hole blocking layer can be formed using, for example, an oxadiazole derivative, a triazole derivative, or a phenanthroline derivative.

  Hereinafter, the polymer according to the present embodiment and the organic EL element including the polymer will be specifically described with reference to Examples and Comparative Examples. In addition, the Example shown below is an example to the last, and the polymer and organic EL element which concern on this embodiment are not limited to the following example.

Example 1
<Synthesis of Polymer A>
First, monomer A was synthesized according to the scheme shown below.

  A 300 ml three-necked flask was charged with 2,7-dibromo-9,9-dimethyl-9H-fluorene (4.86 g, 13.8 mmol), purged with argon, and then 50 ml of dehydrated tetrahydrofuran (THF, Tetrahhydrofuran) was added and dried. Cooled with ice / acetone. Subsequently, 5.6 ml of 2.6 M normal butyl lithium hexane solution was dropped. After aging for 1 hour, the mixture was cooled again with a refrigerant, 1.7 ml of dehydrated N, N-dimethylformamide (DMF, N, N-dimethylformamide) was added dropwise, and the mixture was stirred for 1 hour. Thereafter, the temperature was returned to room temperature, and impurities were filtered off using celite. Water was added to the filtrate, followed by extraction with toluene, and the extracted organic layer was concentrated. The concentrated solution was purified by a column chromatogram to obtain Compound 1.

  Compound 1 (4.16 g, 13.8 mmol), diphenylaminophenylboronic acid (4.63 g, 15.2 mmol), tetrakistriphenylphosphine palladium (0.48 g, 0.41 mmol) in a reaction bath under argon, 30 ml of 1,2-dimethoxyethane and 16.5 ml of 2M aqueous sodium carbonate solution were added, and the mixture was stirred at 80 ° C. for 7 hours. After allowing to cool to room temperature, extraction was performed three times with toluene / water, and the organic layer was concentrated and purified using a column chromatogram to obtain Compound 2.

  Under argon, triphenylmethylphosphonium bromide (4.07 g, 11.4 mmol) and 30 ml of dehydrated THF were added to the reaction bath and cooled in an ice bath. Subsequently, a solution in which tBuOK (1.29 g, 11.5 mmol) was dissolved in 30 ml of dehydrated THF was added dropwise. Then, a solution of compound 2, 5.28 g (11.0 mmol) dissolved in 30 ml of dehydrated THF was added dropwise. After completion of dropping, the mixture was returned to room temperature and stirred for 3 hours. After completion of the reaction, the mixture was extracted with toluene / water three times, and the organic layer was concentrated and purified using a column chromatogram to obtain monomer A. The structure of monomer A was identified using a high performance liquid chromatograph mass spectrometer (LC-MS).

  Next, polymer A shown below was formed from monomer A and vinylcarbazole. Monomer A (0.50 g, 1.04 mmol), vinylcarbazole (0.50 g, 2.59 mmol), azobisisobutyronitrile (AIBN, azobisisobutyronitrile) (0.005 g, 0.004 g) in a reaction bath under argon. 0305 mmol) and 10 ml of dehydrated toluene were added, and the mixture was stirred at 80 ° C. for 8 hours under an argon flow. After allowing to cool to room temperature, methanol was added and the precipitate was filtered. The obtained solid was dissolved in THF and purified by reprecipitation treatment with acetone to obtain 0.24 g of polymer A containing the units shown below. As a result of measurement by gel permeation chromatography (GPC), the molecular weight of polymer A was number average molecular weight (Mn) = 29,100 and weight average molecular weight (Mw) = 79,100). In the polymer A, n: m for each of the following units was 7: 3.

<Measurement of glass transition temperature>
About the obtained polymer A, the glass transition temperature (Tg) was measured. The glass transition temperature was measured using SII DSC6220 (manufactured by Seiko Instruments Inc.) according to JIS K7121.

<Membrane stability evaluation>
The stability of the film formed using the obtained polymer A was evaluated as follows. A spin coat method is applied to a glass substrate with ITO on which indium tin oxide (ITO) is formed to a film thickness of 150 nm from a 1% by mass solution of polymer A in xylene to a film thickness of 30 nm. A film was formed.
The obtained film surface was observed with an optical microscope, and the state of the film was evaluated. The state of the film was evaluated according to the following criteria.
○: Uniform and defect-free △: A small number of dark spots are visible, but the device can be created. ×: The continuity of the film cannot be secured and the device cannot be created.

<Manufacture of organic EL elements>
Next, the organic EL element containing the polymer according to the present embodiment was manufactured by the following steps.

First, as a first electrode (anode), PEDOT / PSS (manufactured by Sigma-Aldrich) was applied on a striped glass substrate with ITO so as to have a dry film thickness of 30 nm by spin coating. An injection layer was formed.
Next, the polymer A synthesized above was dissolved at 1% by mass in xylene to prepare a hole transport layer coating solution. On the hole injection layer, the hole transport layer coating solution was applied by spin coating so that the dry film thickness was 30 nm, and heated at 230 ° C. for 1 hour to form a hole transport layer.

  Subsequently, as a host material, triphenylsilyl, 3,6-biscarbazoylbenzene (TPSmCP), and 4,4′-bis (carbazol-9-yl) biphenyl (CBP), a dopant are formed on the hole transport layer. As a material, tris (2- (3-p-xyyl) phenyl) pyridine iridium (III) was co-evaporated with a vacuum deposition apparatus to form a light-emitting layer having a thickness of 30 nm. In addition, the ratio of TPSmCP and CBP was TPSmCP: CBP = 7: 3 in mass ratio, and the doping amount of tris (2- (3-p-xyyl) phenyl) pyridine iridium (III) was 10% by mass. .

  Next, (8-quinolinolato) lithium (Liq) and KLET-03 (manufactured by Chemipro Kasei) were co-evaporated on the light emitting layer with a vacuum deposition apparatus to form an electron transport layer having a thickness of 50 nm. Moreover, lithium fluoride (LiF) was vapor-deposited on the electron carrying layer with the vacuum evaporation system, and the 1-nm-thick electron injection layer was formed. Furthermore, on the electron injection layer, aluminum was vapor-deposited with the vacuum evaporation system, and the 2nd electrode (cathode) with a film thickness of 100 nm was formed. The organic EL element was created by the above method.

<Evaluation of organic EL element>
The current efficiency and light emission lifetime of the organic EL device prepared above were evaluated by the following methods.
A predetermined voltage was applied to each organic EL element using a DC constant voltage power source (KEYENCE source meter) to cause the organic EL element to emit light. While measuring the light emission of the organic EL element with a luminance measuring device (SR-3 manufactured by Topcom), the current was gradually increased, and when the luminance reached 3000 cd / m ² , the current density was measured and the current was kept constant. I left it alone. The “current efficiency” was calculated from the obtained current density.

In addition, the time until the luminance value measured by the luminance measuring apparatus gradually decreased to 80% of the initial luminance was defined as “light emission lifetime”.
The evaluation results are shown in Table 1. In Table 1, the current efficiency and the light emission lifetime are shown as relative values when the measured value in Comparative Example 1 is 100.

(Examples 2-3, Comparative Examples 1-2)
A device was prepared and evaluated in the same manner as in Example 1 except that the hole transport layer was formed of the polymer shown in Table 1. The results are shown in Table 1.
The monomers used in the polymerization of the polymers B, C, and b were synthesized according to the following reaction scheme.

  Referring to the results in Table 1, in Examples 1 to 3 in which the copolymer according to this embodiment is used for the hole transport layer, the copolymer has a higher Tg and film stability than Comparative Example 2. It was good.

  Further, in Examples 1 to 3 in which the copolymer according to the present embodiment is used for the hole transport layer, the current efficiency and the light emission lifetime are improved with respect to Comparative Example 1, and the copolymer according to the present embodiment is improved. It can be seen that the coalescence has high performance as a hole transporting material.

  As can be seen from the above results, the polymer according to the present embodiment can be efficiently formed by a solution coating method, and can improve the current efficiency and light emission lifetime of the organic EL element. is there.

  The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited to such examples. It is obvious that a person having ordinary knowledge in the technical field to which the present invention pertains can come up with various changes or modifications within the scope of the technical idea described in the claims. Of course, it is understood that these also belong to the technical scope of the present invention.

DESCRIPTION OF SYMBOLS 100 Organic EL element 110 Substrate 120 1st electrode 130 Hole injection layer 140 Hole transport layer 150 Light emitting layer 160 Electron transport layer 170 Electron injection layer 180 Second electrode

Claims (15)

A copolymer comprising a unit represented by the following general formula (1) and a unit represented by the following general formula (2).

In the above formula,
R ^{1 to} R ⁷ are a hydrogen atom, deuterium atom, halogen atom, hydroxy group, amino group, nitro group, cyano group, substituted or unsubstituted silyl group, substituted or unsubstituted alkyl group having 1 to 20 carbon atoms. Substituted or unsubstituted cycloalkyl group having 3 to 16 ring carbon atoms, substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, substituted or Unsubstituted cycloalkoxy group having 3 to 16 carbon atoms, substituted or unsubstituted aryloxy group having 6 to 30 ring carbon atoms, substituted or unsubstituted aralkyl group having 7 to 40 carbon atoms, substituted or unsubstituted A heteroaryl group having 5 to 30 ring carbon atoms, a substituted or unsubstituted alkylamino group having 1 to 20 carbon atoms, a substituted or unsubstituted ring structure having 6 to 30 carbon atoms An arylamino group,
L ¹ and L ² are each independently a single bond, a substituted or unsubstituted alkylene group having 1 to 10 carbon atoms, a substituted or unsubstituted cycloalkylene group having 5 to 30 carbon atoms, a substituted or unsubstituted ring. An arylene group having 6 to 30 carbon atoms, a heteroarylene group having 6 to 30 ring atoms, or a substituted or unsubstituted amino group,
Cz is a group having a carbazole structure or an azacarbazole structure;
M is a group represented by-(AB) _n -A _m -or-(BA) _n -B _m- ;
here,
n is an integer of 1 to 20,
m is 0 or 1,
p is an integer of 1 to 10,
A is a group having a fluorene structure or an azafluorene structure,
B is a group represented by the general formula (3),

In the general formula (3),
L ³ and L ⁴ each independently represent a single bond, a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkylene group having 3 to 16 ring carbon atoms, substituted or unsubstituted. An arylene group having 6 to 30 ring carbon atoms, a substituted or unsubstituted oxyalkylene group having 1 to 20 carbon atoms, a substituted or unsubstituted oxycycloalkylene group having 3 to 16 ring carbon atoms, a substituted or unsubstituted group. Oxyarylene group having 6 to 30 ring carbon atoms, substituted or unsubstituted aralkylene group having 7 to 40 carbon atoms, substituted or unsubstituted heteroarylene group having 5 to 30 ring carbon atoms, substituted or unsubstituted carbon number An aminoalkylene group having 1 to 20 amino acids, a substituted or unsubstituted aminoarylene group having 6 to 30 ring carbon atoms, an alkyl group or an aryl group; A conversion has been silylene group,
R ⁸ represents a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 16 ring carbon atoms, or a substituted or unsubstituted ring carbon number 6 to 30. Aryl group, substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkoxy group having 3 to 16 ring carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 ring carbon atoms Group, substituted or unsubstituted aralkyl group having 7 to 40 carbon atoms, substituted or unsubstituted heteroaryl group having 5 to 30 ring carbon atoms, substituted or unsubstituted alkylamino group having 1 to 20 carbon atoms, substituted or An unsubstituted arylamino group having 6 to 30 carbon atoms, or a cyclic group formed by combining these groups with the L ₃ or the L ₄ ;
* Represents a binding site with another group. Said A is group represented by following General formula (4), The copolymer of Claim 1 couple | bonded with another group in any substitution position.

In the general formula (4),
R ^{9 to} R ¹² are each independently a hydrogen atom, a halogen atom, a hydroxy group, an amino group, a nitro group, a cyano group, a substituted or unsubstituted silyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms. Group, substituted or unsubstituted cycloalkyl group having 3 to 16 ring carbon atoms, substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, substituted Or an unsubstituted cycloalkoxy group having 3 to 16 ring carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 30 ring carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 40 carbon atoms, substituted or unsubstituted Substituted heteroaryl group having 5 to 30 ring carbon atoms, substituted or unsubstituted alkylamino group having 1 to 20 carbon atoms, substituted or unsubstituted ring carbon atoms having 6 to 20 carbon atoms 0 arylamino group, a substituted or unsubstituted ring formed C6-30 aryl sulfoxide group or adjacent cyclic group these groups are bonded to each other to form,
a and b are each independently an integer of 1 to 4,
X ^{1 to} X ⁸ are each independently a methine group or a nitrogen atom. X ^{1 to} X ⁸ have a methine group,
The copolymer according to claim 2, wherein R ⁹ and R ¹⁰ are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms. L ¹ represents a single bond, a substituted or unsubstituted cycloalkylene group having 5 to 30 carbon atoms, a substituted or unsubstituted arylene group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted ring atom having 6 to 30 ring atoms. The copolymer according to any one of claims 1 to 3, which is a heteroarylene group. The Cz is a group represented by the following general formula (5) or a group in which a plurality of groups represented by the general formula (5) are connected. Polymer.

In the above formula, Y ^{1 to} Y ⁸ are each independently a nitrogen atom or a methine group,
R ^{13 to} R ¹⁵ are each independently a hydrogen atom, a halogen atom, a hydroxy group, an amino group, a nitro group, a cyano group, a substituted or unsubstituted silyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms. Group, substituted or unsubstituted aminoalkyl group having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl group having 3 to 16 ring carbon atoms, substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, A substituted or unsubstituted aminoaryl group having 6 to 30 ring carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 30 ring carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, substituted or Unsubstituted cycloalkoxy group having 3 to 16 ring carbon atoms, substituted or unsubstituted aryloxy group having 6 to 30 ring carbon atoms, substituted or unsubstituted carbon A 7 to 40 aralkyl group, a substituted or unsubstituted alkylamino group having 1 to 20 carbon atoms, a substituted or unsubstituted arylamino group having 6 to 30 ring carbon atoms, or adjacent groups bonded to each other; A formed cyclic group, or a bond with another group,
c and d are each independently an integer of 0 to 4. The Cz is a group represented by the following general formula (6) or (7) or a group in which a plurality of groups represented by the general formula (6) or (7) are connected. Polymer.

In the formula, * is a binding site with another group. Furthermore, the copolymer as described in any one of Claims 1-6 in which the polymerizable comonomer which has at least 1 or more of the crosslinking groups selected from the following crosslinking group group is contained as a polymerization unit.

In the above crosslinking group group,
R ^{15 to} R ²¹ are a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms,
p is an integer of 1-10. The copolymer according to claim 7, wherein the polymerizable comonomer is a compound represented by the following general formula (8).

In the general formula (8),
R ^{22 to} R ²⁴ are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms,
R ^{25 to} R ²⁹ are each independently a hydrogen atom, a halogen atom, a hydroxy group, an amino group, a nitro group, a cyano group, a substituted or unsubstituted silyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms. Group, substituted or unsubstituted cycloalkyl group having 3 to 16 ring carbon atoms, substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, substituted Or an unsubstituted cycloalkoxy group having 3 to 16 ring carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 30 ring carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 40 carbon atoms, substituted or unsubstituted Substituted heteroaryl group having 5 to 30 ring carbon atoms, substituted or unsubstituted alkylamino group having 1 to 20 carbon atoms, substituted or unsubstituted ring carbon number 6 30 arylamino group or an adjacent cyclic group these groups are bonded to each other to form,
L ⁵ is a single bond, a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkylene group having 3 to 16 ring carbon atoms, a substituted or unsubstituted ring forming carbon atom having 6 to 30 carbon atoms. An arylene group, a substituted or unsubstituted oxyalkylene group having 1 to 20 carbon atoms, a substituted or unsubstituted oxycycloalkylene group having 3 to 16 ring carbon atoms, a substituted or unsubstituted ring forming carbon atom having 6 to 30 carbon atoms An oxyarylene group, a substituted or unsubstituted aralkylene group having 7 to 40 carbon atoms, a substituted or unsubstituted heteroarylene group having 5 to 30 ring carbon atoms, a substituted or unsubstituted aminoalkylene group having 1 to 20 carbon atoms, A substituted or unsubstituted aminoarylene group having 6 to 30 ring carbon atoms, or a silylene group substituted with an alkyl group or an aryl group,
At least one of R ^{25 to} R ²⁹ is a crosslinking group selected from the group of crosslinking groups. The copolymer according to claim 8, wherein L ⁵ is a group represented by the following general formula (9).

In the general formula (9),
A ′ is a group represented by the general formula (3),
B ′ is a group having a fluorene structure or an azafluorene structure;
r is an integer of 1 to 20,
* Is a binding site with a fluorenylene group. The copolymer according to claim 8, wherein L ⁵ is a group represented by the general formula (3). A pair of electrodes;
And at least one organic layer disposed between the pair of electrodes,
The organic electroluminescent element in which at least 1 layer of the said organic layer contains the copolymer of any one of Claims 1-10.   The organic electroluminescence device according to claim 11, wherein at least one of the organic layers is a hole transport layer containing the copolymer.   The organic electroluminescent element according to claim 11 or 12, wherein at least one of the organic layers is a light emitting layer containing a light emitting material capable of emitting light from triplet excitons.   The organic electroluminescent element material containing the copolymer as described in any one of Claims 1-10.   The composition for organic electroluminescent element manufacture containing the copolymer as described in any one of Claims 1-10, and a liquid medium.

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