JP5845599B2 - Organic electroluminescence element, display device and lighting device - Google Patents

Description

  The present invention relates to an organic electroluminescence element, a display device, and a lighting device.

  Conventionally, as a light-emitting electronic display device, there is an electroluminescence display (hereinafter referred to as ELD). Examples of the constituent elements of ELD include inorganic electroluminescent elements and organic electroluminescent elements (hereinafter also referred to as organic EL elements). Inorganic electroluminescent elements have been used as planar light sources, but an alternating high voltage is required to drive the light emitting elements. An organic EL device has a structure in which a light emitting layer containing a compound that emits light is sandwiched between a cathode and an anode, and injects electrons and holes into the light emitting layer and recombines them to generate excitons. An element that emits light by using light emission (fluorescence / phosphorescence) when the exciton is deactivated, can emit light at a voltage of several V to several + V, and is self-luminous. Therefore, it has a wide viewing angle, high visibility, and since it is a thin-film type complete solid-state device, it has attracted attention from the viewpoints of space saving and portability.

  However, in organic EL elements for practical use in the future, development of organic EL elements that emit light efficiently and with high luminance with lower power consumption is desired. In addition, there have been reports on organic EL elements using compounds having nitrogen-containing heterocycles as materials that aim at materials with high efficiency and low voltage (for example, Patent Documents 1 to 3). There is a need for higher efficiency and lower voltage drive.

  On the other hand, Patent Document 4 reports that an organic EL element uses a compound having a condensed heterocyclic ring in which at least four rings containing a 1-azabicyclo [3.3.0] octane partial structure are condensed. There is a description that high-efficiency and low-voltage driving is possible by using a compound containing the partial structure in the element. Patent Document 4 is a report using a compound in which the condensed heterocycle is directly bonded to an organic EL element or a compound in which a (hetero) aromatic monocycle is connected. However, the luminous efficiency and low voltage drivability of the organic EL element are reported. Further improvement still remains as a problem, and further extension of the light emission lifetime is an important issue.

JP 2002-1000047 A JP 2004-171808 A JP 2007-288035 A JP 2010-87496 A

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an organic EL element that exhibits high light emission efficiency and low voltage drivability, and has a long light emission lifetime, an illumination device using the organic EL element, and a display To provide an apparatus.

  The above object of the present invention is achieved by the following configurations.

  1. An organic electroluminescence device having at least one organic layer including a light emitting layer between a pair of electrodes, wherein at least one of the organic layers has a compound represented by the following general formula (1). Organic electroluminescence device.

（一般式（ｉ）中、Ｘは一般式（２）を表し、Ａｒ^１は６員環の芳香族環であり、１つ以上の基Ｒ^１によって置換されていてもよく、Ｔ^１は単結合、Ｒ^１はＨまたは置換基を表す。）
２．前記一般式（１）中、ｎ_１が２〜４の整数を表すことを特徴とする前記１に記載の有機エレクトロルミネッセンス素子。
３．前記一般式（１）中、Ｌ_１が複素芳香族縮合環であることを特徴とする前記１または２に記載の有機エレクトロルミネッセンス素子。 (In General Formula (1), X represents General Formula (2), and n ₁ represents an integer of ₁ to 4. When n ₁ is 2 or more, each X may be the same or different. In general formula (2), A _{101 to} A ₁₁₁ each represent N or C—R, each R independently represents a hydrogen atom, a substituent or a bond to L ₁ , n ₁ = 2 to 2 In the case of 4, L ₁ represents an aromatic condensed ring or a heteroaromatic condensed ring, and when n ₁ = 1, L ₁ represents a naphthalene ring, anthracene ring, tetracene ring, pyrene ring, phenanthrene ring, phenalene ring, triphenylene Ring, coronene ring, quinoline ring, benzoborol ring, isoindole ring, indole ring, benzofuran ring, phosphinoindole ring, phosphinoindole oxide ring, benzosilol ring, benzothiophene ring, benzodiborol , Benzodifuran ring, benzodithiophene ring, benzo dicyanamide roll ring, dibenzothiophene ball roll ring, a carbazole ring, a dibenzofuran ring, benzoin phosphino indole ring, is selected from dibenzosilole ring and a dibenzothiophene ring, fused aromatic ring or heterocyclic Represents an aromatic condensed ring, and when the aromatic condensed ring or the heteroaromatic condensed ring has a substituent, the substituents are not connected to form a ring , and L ₁ is a general formula. It is not a skeleton structure represented by (2) L ₁ and X are bonded via a carbon atom constituting L ₁ , provided that the compound is represented by the following general formula (i) Is excluded.)

(In the general formula (i), X represents the general formula (2), Ar ¹ is a 6-membered aromatic ring, which may be substituted by one or more groups R ¹ , and T ¹ is a simple group. Bond, R ¹ represents H or a substituent.)
2. In Formula (1) The organic electroluminescent device according to the 1 n ₁ is equal to or an integer of 2-4.
3. Formula (1), an organic electroluminescent device described in 1 or 2 L ₁ is characterized in that it is a heteroaromatic fused rings.

4 . The organic electroluminescent device according to the 3, characterized in that in said formula (1), L ₁ is represented by the general formula (3).

(In General Formula (3), A _{201 to} A ₂₀₈ represent N or C—R, and Y ₁ represents O, S, NR ′, BR ′, SiR′R ″, PR ′ or P (Z ₁ ) R ′. R, R ′ and R ″ each independently represents a hydrogen atom, a substituent or a bond, and Z ₁ represents O or S.)
5. Formula (3), an organic electroluminescent device according to the 4, characterized in that Y ₁ is represented by O or S.
6 . In the general formula (3), R, R ′, and R ″ are represented by a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, an alkynyl group, an aryl group, an aromatic heterocyclic ring, a heterocyclic group, or an alkoxy group. 5. The organic electroluminescence device as described in 4 above.

7 . 7. The organic electroluminescence device as described in 6 above, wherein the compound represented by the general formula (1) is a compound represented by the general formula (4).

(In General Formula (4), A _{301 to} A ₃₃₀ represent N or C—R, and Y ₂ represents O, S, NR ′, BR ′, SiR′R ″, PR ′ or P (Z ₂ ) R. R represents R, R ′ and R ″ each independently represents a hydrogen atom, a substituent or a bond, and Z ₂ represents O or S.)
8 . 8. The organic electroluminescence device according to 7 above, wherein Y ₂ is represented by O or S in the compound represented by the general formula (4).

（一般式（１）中、Ｘは一般式（２）を表し、ｎ_１は１〜４の整数を表す。ｎ_１が２以上の場合、それぞれのＸは同一であっても異なっていても良い。また、一般式（２）中、Ａ_１０１〜Ａ_１１１はＮまたはＣ−Ｒを表す。Ｒはそれぞれ独立に水素原子、置換基またはＬ_１との結合手を表す。Ｌ_１は芳香族縮合環または複素芳香族縮合環を表し、一般式（２）で表される骨格構造であることはない。Ｌ_１とＸとは、Ｌ_１を構成する炭素原子を介して結合している。但し、下記一般式（ii）、式（Ｉ−２９）、式（Ｉ−３０）、式（Ｉ−４４）、式（Ｉ−４５）、式（Ｉ−４９）、式（Ｉ−５０）、式（Ｉ−５４）および式（Ｉ−５５）で表される化合物を除く。）

（一般式（ii）中、Ｘは一般式（２）で定義したとおりであり；
Ｔ^１、Ｔ^２、Ｔ^３は、単結合であり；
Ａｒ^１は６個の芳香環原子を有する芳香族環系であり、これは１つ以上の基Ｒ^１によって置換されていてもよく；
Ｒ^１は、出現するごとに同一または異なり、Ｈ、Ｄ、Ｆ、Ｃｌ、Ｂｒ、Ｉ、ＣＨＯ、Ｎ（Ｒ^３）_２、Ｃ（＝Ｏ）Ｒ^３、Ｐ（＝Ｏ）（Ｒ^３）_２、Ｓ（＝Ｏ）Ｒ^３、Ｓ（＝Ｏ）_２Ｒ^３、ＣＲ^３＝Ｃ（Ｒ^３）_２、ＣＮ、ＮＯ_２、Ｓｉ（Ｒ^３）_３、Ｂ（ＯＲ^３）_２、ＯＳＯ_２Ｒ^３、ＯＨ、１〜４０個のＣ原子を有する直鎖のアルキル基、アルコキシ基もしくはチオアルキル基、または３〜４０個のＣ原子を有する分岐もしくは環状のアルキル基、アルコキシ基もしくはチオアルキル基、または２〜４０個のＣ原子を有するアルケニル基もしくはアルキニル基（これらの各々は１以上の基Ｒ^３によって置換されていてもよい）（ここで、１つ以上の隣接しないＣＨ_２基は、Ｒ^３Ｃ＝ＣＲ^３、Ｃ≡Ｃ、Ｓｉ（Ｒ^３）_２、Ｇｅ（Ｒ^３）_２、Ｓｎ（Ｒ^３）_２、Ｃ＝Ｏ、Ｃ＝Ｓ、Ｃ＝Ｓｅ、Ｃ＝ＮＲ^３、Ｐ（＝Ｏ）（Ｒ^３）、ＳＯ、ＳＯ_２、ＮＲ^３、Ｏ、ＳまたはＣＯＮＲ^３によって置きかえられていてもよく、１つ以上のＨ原子は、Ｄ、Ｆ、Ｃｌ、Ｂｒ、Ｉ、ＣＮ、またはＮＯ_２によって置きかえられていてもよい）、または５〜６０個の芳香環原子を有する単環もしくは多環の芳香族環系もしくはヘテロ芳香族環系（これは各々の場合において１つ以上の非芳香族基Ｒ^３によって置換されていてもよい）、または５〜６０個の芳香環原子を有するアリールオキシ基もしくはヘテロアリールオキシ基（これは１つ以上の非芳香族基Ｒ^３によって置換されていてもよい）、またはこれらの系の組合せであり、ここで、２つ以上の基Ｒ^１は、互いに連結していてもよく、単環または多環の脂肪族環系または芳香族環系を形成していてもよく；
Ｒ^３は、出現するごとに同一または異なり、Ｈ、Ｄ、Ｆ、Ｃｌ、Ｂｒ、Ｉ、ＣＨＯ、Ｎ（Ｒ^４）２、Ｃ（＝Ｏ）Ｒ^４、Ｐ（＝Ｏ）（Ｒ^４）_２、Ｓ（＝Ｏ）Ｒ^４、Ｓ（＝Ｏ）_２Ｒ^４、ＣＲ^４＝Ｃ（Ｒ^４）_２、ＣＮ、ＮＯ_２、Ｓｉ（Ｒ^４）_３、Ｂ（ＯＲ^４）_２、ＯＳＯ_２Ｒ^４、ＯＨ、１〜４０個のＣ原子を有する直鎖のアルキル基、アルコキシ基もしくはチオアルキル基、または３〜４０個のＣ原子を有する分岐もしくは環状のアルキル基、アルコキシ基もしくはチオアルキル基、または２〜４０個のＣ原子を有するアルケニル基もしくはアルキニル基（これらの各々は、１つ以上の基Ｒ^４によって置換されていてもよい）（ここで、１つ以上の隣接しないＣＨ_２基は、Ｒ^４Ｃ＝ＣＲ^４、Ｃ≡Ｃ、Ｓｉ（Ｒ^４）_２、Ｇｅ（Ｒ^４）_２、Ｓｎ（Ｒ^４）_２、Ｃ＝Ｏ、Ｃ＝Ｓ、Ｃ＝Ｓｅ、Ｃ＝ＮＲ^４、Ｐ（＝Ｏ）（Ｒ^４）、ＳＯ、ＳＯ_２、ＮＲ^４、Ｏ、ＳまたはＣＯＮＲ^４によって置きかえられていてもよく、１つ以上のＨ原子は、Ｄ、Ｆ、Ｃｌ、Ｂｒ、Ｉ、ＣＮ、またはＮＯ_２によって置きかえられていてもよい）、または５〜６０個の芳香環原子を有する単環もしくは多環の芳香族環系もしくはヘテロ芳香族環系（これは各々の場合において１つ以上の非芳香族基Ｒ^４によって置換されていてもよい）、または５〜６０個の芳香環原子を有するアリールオキシ基もしくはヘテロアリールオキシ基（これは１つ以上の非芳香族基Ｒ^４によって置換されていてもよい）、またはこれらの系の組合せであり、ここで、２つ以上の基Ｒ^３は、互いに連結していてもよく、単環または多環の脂肪族環系または芳香族環系を形成していてもよく；
Ｒ^４は、出現するごとに同一または異なり、Ｈ、Ｄ、Ｆまたは１〜２０個のＣ原子を有する脂肪族、芳香族および／または複素芳香族有機基（ここで、さらに、１つ以上のＨ原子は、ＤまたはＦによって置きかえられていてもよい）であり；ここで２つ以上の同一または異なった置換基Ｒ^４は、また、互いに連結していてもよく、単環または多環の脂肪族環系または芳香族環系を形成していてもよく；
ｍ１、ｍ２、ｍ３は、出現するごとに同一または異なり、０または１であり、ここで、ｍ１、ｍ２またはｍ３＝０のとき、それぞれ、基Ｒ^１は基Ｔ^１、Ｔ^２またはＴ^３の代わりに結合され；
ｐは１に等しい。）

（式（Ｉ−２９）、式（Ｉ−３０）、式（Ｉ−４４）、式（Ｉ−４５）、式（Ｉ−４９）、式（Ｉ−５０）、式（Ｉ−５４）および式（Ｉ−５５）中、Ｌは、出現するごとに同一または異なり、ＢＲ^２、Ｃ（Ｒ^２）_２、Ｒ^２Ｃ＝ＣＲ^２、Ｓｉ（Ｒ^２）_２、Ｃ＝Ｏ、Ｃ＝ＮＲ^２、Ｏ、Ｓ、ＳＯ、ＳＯ_２、ＰＲ^２、ＰＯＲ^２およびＮＲ^２から選択され；
Ｒ^１は、一般式（ii）において定義されたとおりであり；
Ｒ^２は、一般式（ii）におけるＲ^１と同義である。）
１０．前記１から９のいずれか一項に記載の有機エレクトロルミネッセンス素子を用いたことを特徴とする表示装置。 9. An organic electroluminescence device having at least one organic layer including a light emitting layer between a pair of electrodes, wherein at least one of the organic layers has a compound represented by the following general formula (1). Organic electroluminescence device.

(In General Formula (1), X represents General Formula (2), and n ₁ represents an integer of ₁ to 4. When n ₁ is 2 or more, each X may be the same or different. good. also, in the general formula _{(2), .L 1 a 101} ~A 111 is representative of a bond to each .R is independently a hydrogen atom, a substituent or _{L 1} representing N or C-R are aromatic It represents a condensed ring or a heteroaromatic condensed ring, and is not a skeleton structure represented by the general formula (2) L ₁ and X are bonded via a carbon atom constituting L ₁ . However, the following general formula (ii) , formula (I-29), formula (I-30) , formula (I-44), formula (I-45), formula (I-49), formula (I-50) And the compounds represented by formula (I-54) and formula (I-55) are excluded.)

(In general formula (ii), X is as defined in general formula (2);
T ¹ , T ² , T ³ are single bonds;
Ar ¹ is an aromatic ring system having 6 aromatic ring atoms, which may be substituted by one or more groups R ¹ ;
R ¹ is the same or different every time it appears, and H, D, F, Cl, Br, I, CHO, N (R ³ ) ₂ , C (═O) R ³ , P (═O) (R ³ ) ₂ , S (= O) R ³ , S (= O) ₂ R ³ , CR ³ = C (R ³ ) ₂ , CN, NO ₂ , Si (R ³ ) ₃ , B (OR ³ ) ₂ , OSO ₂ R ³ , OH, a linear alkyl group having 1 to 40 C atoms, an alkoxy group or a thioalkyl group, or a branched or cyclic alkyl group having 3 to 40 C atoms, an alkoxy group or a thioalkyl group, or An alkenyl or alkynyl group having 2 to 40 C atoms, each of which may be substituted by one or more groups R ³ , wherein one or more non-adjacent CH ₂ groups are R ^{3 C = CR 3, C≡C, Si} (R 3) 2, _{^{e (R 3) 2, Sn}} (R 3) 2, C = O, C = S, C = Se, C = NR 3, P (= O) (R 3), SO, SO 2, NR 3, O , S or CONR ³ , one or more H atoms may be replaced by D, F, Cl, Br, I, CN, or NO ₂ ), or 5-60 A monocyclic or polycyclic aromatic ring system or heteroaromatic ring system having 5 aromatic ring atoms, which in each case may be substituted by one or more non-aromatic groups R ³ , or 5 An aryloxy or heteroaryloxy group having ˜60 aromatic ring atoms (which may be substituted by one or more non-aromatic groups R ³ ), or a combination of these systems, Two or more groups R ¹ are connected to each other May form a monocyclic or polycyclic aliphatic ring system or an aromatic ring system;
R ³ is the same or different every time it appears, and H, D, F, Cl, Br, I, CHO, N (R ⁴ ) 2, C (═O) R ⁴ , P (═O) (R ⁴ ) ₂ , S (= O) R ⁴ , S (= O) ₂ R ⁴ , CR ⁴ = C (R ⁴ ) ₂ , CN, NO ₂ , Si (R ⁴ ) ₃ , B (OR ⁴ ) ₂ , OSO ₂ R ⁴ , OH, a linear alkyl group having 1 to 40 C atoms, an alkoxy group or a thioalkyl group, or a branched or cyclic alkyl group having 3 to 40 C atoms, an alkoxy group or a thioalkyl group, or An alkenyl or alkynyl group having 2 to 40 C atoms, each of which may be substituted by one or more groups R ⁴ , wherein one or more non-adjacent CH ₂ groups are ^{R 4 C = CR 4, C≡C} , Si (R 4) 2 _{^{Ge (R 4) 2, Sn}} (R 4) 2, C = O, C = S, C = Se, C = NR 4, P (= O) (R 4), SO, SO 2, NR 4, O , S or CONR ⁴ and one or more H atoms may be replaced by D, F, Cl, Br, I, CN, or NO ₂ ), or 5-60 A monocyclic or polycyclic aromatic ring system or heteroaromatic ring system having 5 aromatic ring atoms, which in each case may be substituted by one or more non-aromatic groups R ⁴ , or 5 An aryloxy or heteroaryloxy group having ˜60 aromatic ring atoms (which may be substituted by one or more non-aromatic groups R ⁴ ), or a combination of these systems, two or more radicals ^{R 3} are communicated with each other May also be, they may form a monocyclic or polycyclic aliphatic ring systems or aromatic ring system;
R ⁴ is the same or different for each occurrence and is an aliphatic, aromatic and / or heteroaromatic organic group having 1 to 20 C atoms, wherein H, D, F or 1 H atom may be replaced by D or F), wherein two or more identical or different substituents R ⁴ may also be linked to each other, monocyclic or polycyclic May form an aliphatic ring system or an aromatic ring system;
m1, m2, m3 are the same or different at each occurrence and are 0 or 1, where when m1, m2 or m3 = 0, the radical R ¹ is a radical of the radical T ¹ , T ² or T ³ , respectively. Instead combined;
p is equal to 1. )

( Formula (I-29), Formula (I-30), Formula (I-44), Formula (I-45), Formula (I-49), Formula (I-50), Formula (I-54) and In formula (I-55), L is the same or different each time it appears, and BR ² , C (R ² ) ₂ , R ² C═CR ² , Si (R ² ) ₂ , C═O, C═NR Selected from ² , O, S, SO, SO ₂ , PR ² , POR ² and NR ² ;
R ¹ is as defined in general formula (ii);
R ² has the same meaning as R ¹ in formula (ii). )
10. 10. A display device using the organic electroluminescence element according to any one of 1 to 9 above.

11 . 10. An illuminating device using the organic electroluminescent element according to any one of 1 to 9 above.

  According to the present invention, it is possible to provide an organic electroluminescence element having high luminous efficiency and low voltage drivability and having a long emission lifetime, and an illumination device and a display device using the organic electroluminescence element.

It is the schematic which shows an example of the illuminating device using the organic EL element of this invention. It is sectional drawing which shows an example of the illuminating device using the organic EL element of this invention.

  Hereinafter, embodiments for carrying out the present invention will be described in detail.

As a result of intensive studies in view of the above problems, the present inventor is an organic electroluminescence device having at least one organic layer including a light emitting layer between a pair of electrodes, and at least one of the organic layers has a general formula. It has been found that the organic EL device having the compound represented by (1) can achieve high luminous efficiency, low voltage driving, and long luminous lifetime, and has reached the present invention. Since the organic EL device of the present invention has a plurality of conjugated condensed ring structures of different shapes, the molecular properties are not biased to one of electron transporting property and hole transporting property, Excellent stability. Furthermore, since the compound represented by the general formula (1) introduces an aromatic condensed ring as L ₁ into the highly condensed heterocyclic ring represented by the general formula (2), the entire molecule has an appropriate twist angle. Have. For this reason, it is assumed that the compatibility of other materials such as the compatibility of the host and dopant in the light-emitting layer is good, and that the energy transfer and carrier transfer are smooth, thereby dramatically improving the performance of the organic EL element. Yes.

  The organic EL device of the present invention is an organic EL device having at least one light emitting layer sandwiched between an anode and a cathode, and contains the compound represented by the general formula (1).

In general formula (1), X represents general formula (2). L ₁ represents an aromatic condensed ring and is not a skeleton structure represented by the general formula (2). In the general formula (2), R represents a hydrogen atom, a substituent, or a bond to L ₁ .

  As the substituent represented by R, those exemplified in the following substituent group can be applied.

  Substituent group: cycloalkoxy group (for example, cyclopentyloxy group, cyclohexyloxy group, etc.), aryloxy group (for example, phenoxy group, naphthyloxy group, etc.), alkylthio group (for example, methylthio group, ethylthio group, propylthio group, pentylthio group) Group, hexylthio group, octylthio group, dodecylthio group, etc.), cycloalkylthio group (eg, cyclopentylthio group, cyclohexylthio group, etc.), arylthio group (eg, phenylthio group, naphthylthio group, etc.), alkoxycarbonyl group (eg, methyloxy Carbonyl group, ethyloxycarbonyl group, butyloxycarbonyl group, octyloxycarbonyl group, dodecyloxycarbonyl group, etc.), aryloxycarbonyl group (for example, phenyloxycarbonyl group, naphthy) Oxycarbonyl group, etc.), sulfamoyl group (for example, aminosulfonyl group, methylaminosulfonyl group, dimethylaminosulfonyl group, butylaminosulfonyl group, hexylaminosulfonyl group, cyclohexylaminosulfonyl group, octylaminosulfonyl group, dodecylaminosulfonyl group, Phenylaminosulfonyl group, naphthylaminosulfonyl group, 2-pyridylaminosulfonyl group, etc.), acyl group (for example, acetyl group, ethylcarbonyl group, propylcarbonyl group, pentylcarbonyl group, cyclohexylcarbonyl group, octylcarbonyl group, 2-ethylhexylcarbonyl) Group, dodecylcarbonyl group, phenylcarbonyl group, naphthylcarbonyl group, pyridylcarbonyl group, etc.), acyloxy group (for example, acetyloxy group) Group, ethylcarbonyloxy group, butylcarbonyloxy group, octylcarbonyloxy group, dodecylcarbonyloxy group, phenylcarbonyloxy group, etc.), amide group (for example, methylcarbonylamino group, ethylcarbonylamino group, dimethylcarbonylamino group, propyl) Carbonylamino group, pentylcarbonylamino group, cyclohexylcarbonylamino group, 2-ethylhexylcarbonylamino group, octylcarbonylamino group, dodecylcarbonylamino group, phenylcarbonylamino group, naphthylcarbonylamino group, etc.), carbamoyl group (for example, aminocarbonyl) Group, methylaminocarbonyl group, dimethylaminocarbonyl group, propylaminocarbonyl group, pentylaminocarbonyl group, cyclohexylaminocarbo group Nyl group, octylaminocarbonyl group, 2-ethylhexylaminocarbonyl group, dodecylaminocarbonyl group, phenylaminocarbonyl group, naphthylaminocarbonyl group, 2-pyridylaminocarbonyl group, etc.), ureido group (for example, methylureido group, ethylureido group) Pentylureido group, cyclohexylureido group, octylureido group, dodecylureido group, phenylureido group, naphthylureido group, 2-pyridylaminoureido group, etc.), sulfinyl group (for example, methylsulfinyl group, ethylsulfinyl group, butylsulfinyl group, (Cyclohexylsulfinyl group, 2-ethylhexylsulfinyl group, dodecylsulfinyl group, phenylsulfinyl group, naphthylsulfinyl group, 2-pyridylsulfinyl group, etc.) Alkylsulfonyl groups (for example, methylsulfonyl group, ethylsulfonyl group, butylsulfonyl group, cyclohexylsulfonyl group, 2-ethylhexylsulfonyl group, dodecylsulfonyl group, etc.), arylsulfonyl groups (for example, phenylsulfonyl group, naphthylsulfonyl group, 2- Pyridylsulfonyl group, etc.), amino group (for example, amino group, ethylamino group, dimethylamino group, butylamino group, cyclopentylamino group, 2-ethylhexylamino group, dodecylamino group, anilino group, naphthylamino group, 2-pyridylamino group) Group), halogen atom (eg, fluorine atom, chlorine atom, bromine atom, etc.), fluorinated hydrocarbon group (eg, fluoromethyl group, trifluoromethyl group, pentafluoroethyl group, pentafluorophenyl group, etc.), Group, silyl group (for example, trimethylsilyl group, triisopropylsilyl group, triphenylsilyl group, phenyldiethylsilyl group, etc.) and the like, more preferably alkyl group (for example, methyl group, ethyl group, propyl group, isopropyl group). Group, t-butyl group, pentyl group, hexyl group, octyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, etc.), cycloalkyl group (for example, cyclopentyl group, cyclohexyl group, etc.), alkenyl group (for example, vinyl) Group, allyl group, etc.), alkynyl group (for example, ethynyl group, propargyl group, etc.), aryl group (for example, phenyl group, p-chlorophenyl group, mesityl group, tolyl group, xylyl group, naphthyl group, anthryl group, azulenyl group) , Acenaphthenyl group, fluorenyl group, phenanthate Aryl group, indenyl group, pyrenyl group, biphenylyl group, etc.), aromatic heterocycle (for example, furyl group, thienyl group, pyridyl group, pyridazyl group, pyrimidyl group, pyrazyl group, triazyl group, imidazolyl group, pyrazolyl group, thiazolyl group) , Benzimidazolyl group, benzoxazolyl group, quinazolyl group, phthalazyl group, etc.), heterocyclic group (eg, pyrrolidyl group, imidazolidyl group, morpholyl group, oxazolidyl group, etc.), alkoxy group (eg, methoxy group, ethoxy group, propyl) Oxy group, pentyloxy group, hexyloxy group, octyloxy group, dodecyloxy group, etc.).

  These groups may further have a substituent, and examples of the further substituent include a group selected from the substituent group described above.

In the general formula _(2), the number of the nitrogen atom of A 101 _{to A 111} is preferably 0 to 4, 0-2 is more preferable.

In the general formula (1) _{n 1} represents an integer of 1 to 4, preferably 1 to 3, more preferably 1 to 2. If n ₁ is 2 or more, each X may be the be the same or different.

In the general formula (1), L ₁ represents an aromatic condensed ring or a heteroaromatic condensed ring, and is not a skeleton structure represented by the general formula (2). The L ₁ can be applied as follows. Aromatic condensed ring (for example, naphthalene ring, anthracene ring, tetracene ring, pyrene ring, phenanthrene ring, phenalene ring, triphenylene ring, coronene ring, quinoline ring, benzoborol ring, isoindole ring, indole ring, benzofuran ring, phosphinoindole Ring, phosphinoindole oxide ring, benzosilole ring, benzothiophene ring, benzodiborol ring, benzodifuran ring, benzodithiophene ring, benzodisilole ring, dibenzoborol ring, carbazole ring, dibenzofuran ring, benzophosphinoindole ring , Dibenzosilole ring, dibenzothiophene ring, etc., more preferably heteroaromatic condensed rings (for example, quinoline ring, benzovolol ring, isoindole ring, indole ring, benzofuran ring, phosphinoin) Ring, phosphinoindole oxide ring, benzosilol ring, benzothiophene ring, benzodiborol ring, benzodifuran ring, benzodithiophene ring, benzodisilole ring, dibenzoborol ring, carbazole ring, dibenzofuran ring, benzophosphino Indole ring, benzophosphinoindole oxide ring, dibenzosilole ring, dibenzothiophene ring, etc.), particularly preferably dibenzoborol ring, carbazole ring, dibenzofuran ring, benzophosphinoindole ring, benzophosphinoindole oxide A ring, a dibenzosilol ring, and a dibenzothiophene ring, and most preferably a dibenzofuran ring and a dibenzothiophene ring. These rings may be further substituted, and examples of the further substituent include groups selected from the substituent group described above, and preferred ranges thereof are also the same.

In the general formula (1), L ₁ is preferably represented by the general formula (3).

In the general formula (3), A _{201 to} A ₂₀₈ represent N or C—R, and Y ₁ represents O, S, NR ′, BR ′, SiR′R ″, PR ′ or P (Z ₁ ) R ′. R, R ′ and R ″ each independently represents a hydrogen atom, a substituent or a bond, and the substituent is preferably selected from the above substituent group. Z ₁ represents O or S. In the general formula _(3), the number of the nitrogen atom of A 201 _{to A 208} is preferably 0 to 4, 0-2 is more preferable.

  Preferably, in the general formula (3), R, R ′ and R ″ are each a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, an alkynyl group, an aryl group, an aromatic heterocyclic ring, a heterocyclic group or an alkoxy group. It is to be done.

  It is preferable that the compound represented by the general formula (1) is represented by the general formula (4).

In General Formula (4), A _{301 to} A ₃₃₀ represent N or C—R, and Y ₂ represents O, S, NR ′, BR ′, SiR′R ″, PR ′ or P (Z ₂ ) R ′. R, R ′ and R ″ each independently represents a hydrogen atom, a substituent or a bond, and Z ₂ represents O or S. Examples of the substituent represented by R include the same substituents as those in the substituent group. R is more preferably an alkyl group, a cycloalkyl group, an alkenyl group, an alkynyl group, an aryl group, an aromatic heterocyclic ring, a heterocyclic group, an alkoxy group, or a hydrogen atom, and R is particularly preferably a hydrogen atom. Examples of the substituent represented by R ′ and R ″ include the same substituents as in the above substituent group. Examples of the substituent represented by R ′ and R ″ include an alkyl group, a cycloalkyl group, an alkenyl group, and an alkynyl group. Are more preferably an aryl group, an aromatic heterocyclic ring, a heterocyclic group or an alkoxy group, and particularly preferably an aryl group, an aromatic heterocyclic ring or a heterocyclic ring. More preferably, Y ₂ includes O and S. In the general formula _(4), the number of the nitrogen atom of A 301 _{to A 330} is preferably 0 to 4, 0-2 is more preferable.

  Specific examples of the compounds represented by the general formulas (1) to (4) are shown below, but the present invention is not limited thereto.

  The compound represented by the general formula (1) according to the present invention is described in, for example, “Journal of Chemical Society, 1939, p. 1945-1956”, and further in these documents. Can be synthesized by referring to the method of the reference.

  In this invention, the compound represented by General formula (1) is contained in the at least 1 layer of organic layer containing the light emitting layer of the organic EL element of this invention. The organic layer refers to a layer containing an organic substance among layers sandwiched between a pair of electrodes. Specifically, the compound represented by the general formula (1) can be used for a hole injection layer, a hole transport layer, a light emitting layer, a hole blocking layer, an electron transport layer, and an electron injection layer described later. Preferably, it is used for a hole transport layer, a light emitting layer, and an electron transport layer. Not only one layer but also a plurality of layers can be included. In this case, it is preferable to include at least in the light emitting layer.

  Further, it is preferably used as a host compound for a light emitting layer, a hole transport layer, and an electron transport layer. The constituent layers and host compounds of the organic EL device of the present invention will be described in detail later.

  Hereinafter, the organic electroluminescence element of the present invention will be described.

<Constitutional layer of organic EL element>
The constituent layers of the organic EL element of the present invention will be described.

In this invention, although the preferable specific example of the layer structure of an organic EL element is shown below, this invention is not limited to these.
Anode / light emitting layer / electron transport layer / cathode anode / hole transport layer / light emitting layer / electron transport layer / cathode anode / hole transport layer / light emitting layer / hole blocking layer / electron transport layer / cathode anode / hole transport Layer / light emitting layer / hole blocking layer / electron transport layer / electron injection layer / cathode anode / hole injection layer / hole transport layer / light emitting layer / hole blocking layer / electron transport layer / electron injection layer / cathode <Anode >
In the present invention, a pair of electrodes refers to an anode and a cathode.

As the anode in the organic EL element, an electrode material made of a metal, an alloy, an electrically conductive compound and a mixture thereof having a high work function (4 eV or more) is preferably used. Specific examples of such an electrode substance include conductive transparent materials such as metals such as Au, CuI, indium tin oxide (ITO), SnO ₂ , and ZnO. Alternatively, an amorphous material such as IDIXO (In ₂ O ₃ —ZnO) capable of forming a transparent conductive film may be used. For the anode, a thin film may be formed by depositing these electrode materials by a method such as vapor deposition or sputtering, and a pattern having a desired shape may be formed by a photolithography method, or when the pattern accuracy is not required (100 μm or more) Degree), a pattern may be formed through a mask having a desired shape when the electrode material is deposited or sputtered. When light emission is extracted from the anode, it is desirable that the transmittance is greater than 10%, and the sheet resistance as the anode is preferably several hundred Ω / □ or less. Further, although the film thickness depends on the material, it is usually selected in the range of 10 to 1000 nm, preferably 10 to 200 nm.

<Cathode>
On the other hand, as the cathode, a material having a low work function (4 eV or less) metal (referred to as an electron injecting metal), an alloy, an electrically conductive compound, and a mixture thereof as an electrode material is used. Specific examples of such electrode materials include sodium, sodium-potassium alloy, magnesium, lithium, magnesium / copper mixture, magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, aluminum / aluminum oxide (Al ₂ O ₃ ) Mixtures, indium, lithium / aluminum mixtures, rare earth metals and the like. Among these, a mixture of an electron injecting metal and a second metal which is a stable metal having a larger work function value than this, such as a magnesium / silver mixture, magnesium, from the viewpoint of electron injectability and durability against oxidation, etc. / Aluminum mixtures, magnesium / indium mixtures, aluminum / aluminum oxide (Al ₂ O ₃ ) mixtures, lithium / aluminum mixtures, aluminum, etc. The cathode can be produced by forming a thin film of these electrode materials by a method such as vapor deposition or sputtering. The sheet resistance as a cathode is preferably several hundred Ω / □ or less, and the film thickness is usually selected in the range of 10 nm to 5 μm, preferably 50 to 200 nm. In order to transmit the emitted light, if either one of the anode or the cathode of the organic EL element is transparent or translucent, the emission luminance is advantageously improved.

  Moreover, after producing the said metal with a film thickness of 1-20 nm on a cathode, a transparent or semi-transparent cathode can be produced by producing the electroconductive transparent material quoted by description of the anode on it, By applying this, an element in which both the anode and the cathode are transmissive can be manufactured. Next, a hole transport layer, an electron transport layer, an injection layer, and the like used as a constituent layer of the organic EL element of the present invention will be described.

<Hole transport layer>
The hole transport layer is made of a hole transport material having a function of transporting holes, and can be provided as a single layer or a plurality of layers.

  The hole transport material has any one of hole injection or transport and electron barrier properties, and may be either organic or inorganic. For example, triazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives and pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, oxazole derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, Examples thereof include stilbene derivatives, silazane derivatives, aniline copolymers, and conductive polymer oligomers, particularly thiophene oligomers.

  The above-mentioned materials can be used as the hole transport material, but it is preferable to use a porphyrin compound, an aromatic tertiary amine compound and a styrylamine compound, particularly an aromatic tertiary amine compound.

  Representative examples of aromatic tertiary amine compounds and styrylamine compounds include N, N, N ', N'-tetraphenyl-4,4'-diaminophenyl; N, N'-diphenyl-N, N'- Bis (3-methylphenyl)-[1,1′-biphenyl] -4,4′-diamine (TPD); 2,2-bis (4-di-p-tolylaminophenyl) propane; 1,1-bis (4-di-p-tolylaminophenyl) cyclohexane; N, N, N ′, N′-tetra-p-tolyl-4,4′-diaminobiphenyl; 1,1-bis (4-di-p-tolyl) Aminophenyl) -4-phenylcyclohexane; bis (4-dimethylamino-2-methylphenyl) phenylmethane; bis (4-di-p-tolylaminophenyl) phenylmethane; N, N'-diphenyl-N, N ' − (4-methoxyphenyl) -4,4'-diaminobiphenyl; N, N, N ', N'-tetraphenyl-4,4'-diaminodiphenyl ether; 4,4'-bis (diphenylamino) quadriphenyl; N, N, N-tri (p-tolyl) amine; 4- (di-p-tolylamino) -4 '-[4- (di-p-tolylamino) styryl] stilbene; 4-N, N-diphenylamino- (2-diphenylvinyl) benzene; 3-methoxy-4′-N, N-diphenylaminostilbenzene; N-phenylcarbazole, and also two of those described in US Pat. No. 5,061,569. Having a condensed aromatic ring in the molecule, for example, 4,4'-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (NPD), JP-A-4-3086 4,4 ', 4 "-tris [N- (3-methylphenyl) -N-phenylamino] triphenylamine in which three triphenylamine units described in Japanese Patent No. 8 are linked in a starburst type ( MTDATA) and the like.

  Furthermore, a polymer material in which these materials are introduced into a polymer chain or these materials are used as a polymer main chain can also be used. In addition, inorganic compounds such as p-type-Si and p-type-SiC can also be used as the hole injection material and the hole transport material.

  JP-A-11-251067, J. Org. Huang et. al. A so-called p-type hole transport material as described in a book (Applied Physics Letters 80 (2002), p. 139) can also be used. In the present invention, it is preferable to use these materials because a light-emitting element with higher efficiency can be obtained.

  The hole transport layer can be formed by thinning the hole transport material by a known method such as a vacuum deposition method, a spin coating method, a casting method, a printing method including an ink jet method, or an LB method. it can. Although there is no restriction | limiting in particular about the film thickness of a positive hole transport layer, Usually, 5 nm-about 5 micrometers, Preferably it is 5-200 nm. The hole transport layer may have a single layer structure composed of one or more of the above materials.

  Alternatively, a hole transport layer having a high p property doped with impurities can be used. Examples thereof include JP-A-4-297076, JP-A-2000-196140, JP-A-2001-102175, J. Pat. Appl. Phys. 95, 5773 (2004), and the like.

  In the present invention, it is preferable to use a hole transport layer having such a high p property because a device with lower power consumption can be produced.

<Electron transport layer>
The electron transport layer is made of a material having a function of transporting electrons, and can be provided as a single layer or a plurality of layers.

  Conventionally, in the case of a single electron transport layer and a plurality of layers, an electron transport material (also serving as a hole blocking material) used for an electron transport layer adjacent to the light emitting layer on the cathode side is injected from the cathode. As long as it has a function of transferring electrons to the light-emitting layer, any material can be selected and used from among conventionally known compounds. For example, nitro-substituted fluorene derivatives, diphenylquinone derivatives Thiopyrandioxide derivatives, carbodiimides, fluorenylidenemethane derivatives, anthraquinodimethane and anthrone derivatives, oxadiazole derivatives and the like. Furthermore, in the above oxadiazole derivative, a thiadiazole derivative in which the oxygen atom of the oxadiazole ring is substituted with a sulfur atom, and a quinoxaline derivative having a quinoxaline ring known as an electron withdrawing group can also be used as an electron transport material. Furthermore, a polymer material in which these materials are introduced into a polymer chain or these materials are used as a polymer main chain can also be used.

  In addition, metal complexes of 8-quinolinol derivatives such as tris (8-quinolinol) aluminum (Alq), tris (5,7-dichloro-8-quinolinol) aluminum, tris (5,7-dibromo-8-quinolinol) aluminum Tris (2-methyl-8-quinolinol) aluminum, tris (5-methyl-8-quinolinol) aluminum, bis (8-quinolinol) zinc (Znq), and the like, and the central metals of these metal complexes are In, Mg, Metal complexes replaced with Cu, Ca, Sn, Ga or Pb can also be used as the electron transport material. In addition, metal-free or metal phthalocyanine, or those having terminal ends substituted with an alkyl group or a sulfonic acid group can be preferably used as the electron transporting material. In addition, the distyrylpyrazine derivative exemplified as the material of the light emitting layer can also be used as an electron transport material, and similarly to the hole injection layer and the hole transport layer, inorganic such as n-type-Si and n-type-SiC can be used. A semiconductor can also be used as an electron transport material.

  The electron transport layer can be formed by thinning the electron transport material by a known method such as a vacuum deposition method, a spin coating method, a casting method, a printing method including an ink jet method, or an LB method. Although there is no restriction | limiting in particular about the film thickness of an electron carrying layer, Usually, 5 nm-about 5 micrometers, Preferably it is 5-200 nm. The electron transport layer may have a single layer structure composed of one or more of the above materials.

  Further, an electron transport layer having a high n property doped with impurities can also be used. Examples thereof include JP-A-4-297076, JP-A-10-270172, JP-A-2000-196140, 2001-102175, J.A. Appl. Phys. 95, 5773 (2004), and the like.

  In the present invention, it is preferable to use an electron transport layer having such a high n property because an element with lower power consumption can be manufactured.

<Injection layer>: Electron injection layer, hole injection layer The injection layer is provided as necessary, and there are an electron injection layer and a hole injection layer, and as described above, between the anode and the light emitting layer or the hole transport layer, and You may exist between a cathode, a light emitting layer, or an electron carrying layer.

  An injection layer is a layer provided between an electrode and an organic layer in order to reduce drive voltage and improve light emission luminance. “Organic EL element and its forefront of industrialization (issued by NTT Corporation on November 30, 1998) 2), Chapter 2, “Electrode Materials” (pages 123 to 166) in detail, and includes a hole injection layer (anode buffer layer) and an electron injection layer (cathode buffer layer). The details of the anode buffer layer (hole injection layer) are described in JP-A Nos. 9-45479, 9-260062, and 8-288069, and a specific example is represented by copper phthalocyanine. Examples thereof include a phthalocyanine buffer layer, an oxide buffer layer typified by vanadium oxide, an amorphous carbon buffer layer, and a polymer buffer layer using a conductive polymer such as polyaniline (emeraldine) or polythiophene. The details of the cathode buffer layer (electron injection layer) are described in JP-A-6-325871, 9-17574, 10-74586, and the like, and specifically, strontium, aluminum, and the like are representative. A metal buffer layer, an alkali metal compound buffer layer typified by lithium fluoride, an alkaline earth metal compound buffer layer typified by magnesium fluoride, and an oxide buffer layer typified by aluminum oxide. The buffer layer (injection layer) is desirably a very thin film, and although it depends on the material, the film thickness is preferably in the range of 0.1 nm to 5 μm.

<Blocking Layer>: Hole Blocking Layer, Electron Blocking Layer As described above, the blocking layer is provided as necessary in addition to the basic constituent layer of the organic compound thin film. For example, JP-A Nos. 11-204258 and 11-204359, and “Organic EL devices and their forefront of industrialization” (published by NTS Corporation on November 30, 1998), etc. There is a hole blocking layer.

  The hole blocking layer is an electron transport layer in a broad sense, and is made of a material that has a function of transporting electrons and has a very small ability to transport holes. By blocking holes while transporting electrons, And the recombination probability of holes can be improved.

  On the other hand, the electron blocking layer is a hole transport layer in a broad sense, made of a material that has a function of transporting holes and has a very small ability to transport electrons, and blocks electrons while transporting holes. Thus, the probability of recombination of electrons and holes can be improved.

<Light emitting layer>
The light emitting layer according to the present invention is a layer that emits light by recombination of electrons and holes injected from the electrode, the electron transport layer, or the hole transport layer, and the light emitting portion is in the layer of the light emitting layer. May be the interface between the light emitting layer and the adjacent layer.

  The material used for the light emitting layer (hereinafter referred to as the light emitting material) is preferably an organic compound or complex that emits fluorescence or phosphorescence, and is appropriately selected from known materials used for the light emitting layer of the organic EL device. Can be used. Such a light-emitting material is mainly an organic compound, and has a desired color tone, for example, Macromol. Synth. 125, pages 17 to 25, and the like. The light emitting material may have a hole transport function and an electron transport function in addition to the light emitting performance, and most of the hole transport material and the electron transport material can be used as the light emitting material. The light emitting material may be a polymer material such as p-polyphenylene vinylene or polyfluorene, and a polymer material in which the light emitting material is introduced into a polymer chain or the light emitting material is used as a polymer main chain is used. May be. The light emitting layer can be formed by forming the above compound by a known thinning method such as a vacuum deposition method, a spin coating method, a casting method, or an LB method. Although the film thickness as a light emitting layer does not have a restriction | limiting in particular, Usually, 5 nm-5 micrometers, Preferably it is chosen in the range of 5-200 nm. This light emitting layer may have a single layer structure composed of one or more of these light emitting materials, or may have a laminated structure composed of a plurality of layers having the same composition or different compositions. A preferred embodiment of the organic EL device of the present invention is when the light emitting layer is composed of two or more materials, and one of them is the compound of the present invention.

  In addition, as described in JP-A-57-51781, this light-emitting layer is prepared by dissolving the above light-emitting material in a solvent together with a binder such as resin to form a thin film by spin coating or the like. Can be formed. There is no restriction | limiting in particular about the film thickness of the light emitting layer formed in this way, Although it can select suitably according to a condition, Usually, it is the range of 5 nm-5 micrometers, Preferably it is the range of 5-200 nm.

(Host compound)
“Host compound (hereinafter also simply referred to as host)” means a compound having the largest mixing ratio (mass) in a light-emitting layer composed of two or more kinds of compounds. It is called “dopant compound (also simply referred to as dopant)”. For example, if the light emitting layer is composed of two types of compound A and compound B and the mixing ratio is A: B = 10: 90, compound A is a dopant compound and compound B is a host compound. Furthermore, if a light emitting layer is comprised from 3 types of compound A, compound B, and compound C, and the mixing ratio is A: B: C = 5: 10: 85, compound A and compound B are dopant compounds, Compound C is a host compound.

  The host compound of the light emitting layer is preferably an organic compound or a complex, and in the present invention, the excited triplet energy of the host compound is preferably larger than the excited triplet energy of the phosphorescent dopant. Further, the wavelength of the 0-0 band in the phosphorescence spectrum of the host compound is preferably 450 nm or less. Thereby, visible light, in particular, BGR emission can be performed. That is, by making the excited triplet energy of the host compound larger than the excited triplet energy of the phosphorescent dopant, energy transfer type dopant emission from the host compound to the dopant is possible. In addition, a compound having a 0-0 band wavelength of 450 nm or less in the phosphorescence spectrum of the host compound has a very wide energy gap (ionization potential-electron affinity, HOMO-LUMO).

  As such a host compound, an arbitrary one can be selected and used from known materials used in organic EL devices, and most of the hole transport materials and electron transport materials described below are light emitting layer host compounds. Can also be used. A polymer material such as polyvinyl carbazole or polyfluorene may be used, and a polymer material in which the host compound is introduced into a polymer chain or the host compound as a polymer main chain may be used.

  As the host compound, a compound that has a hole transporting ability and an electron transporting ability, prevents the emission of light from being increased in wavelength, and has a high Tg (glass transition temperature) is preferable.

  Here, in the present invention, the host compound is a phosphorescent quantum yield of phosphorescence emission at a room temperature (25 ° C.) of a compound contained in the light emitting layer having a mass ratio of 20% or more in the layer. Is defined as a compound of less than 0.1. The phosphorescence quantum yield is preferably less than 0.01.

  As the host compound of the light emitting layer, it is preferable to use the compounds represented by the general formulas (1) to (4) according to the present invention, but they may be known host compounds or may be used in combination. . As a known host compound that may be used in combination, a compound that has a hole transporting ability and an electron transporting ability, prevents the emission of light from being increased in wavelength, and has a high Tg (glass transition temperature) is preferable.

  Specific examples of known host compounds include compounds described in the following documents.

  JP-A-2001-257076, 2002-308855, 2001-313179, 2002-319491, 2001-357777, 2002-334786, 2002-8860, 2002-334787, 2002-15871, 2002-334788, 2002-43056, 2002-334789, 2002-75645, 2002-338579, 2002-105445, 2002-343568, 2002-14173, 2002-352957, 2002-203683, 2002-363227, 2002-23153, 20 No. 3-3165, No. 2002-234888, No. 2003-27048, No. 2002-2934, No. 2002-286061, No. 2002-280183, No. 2002-299060, No. 2002. -302516, 2002-305083, 2002-305084, 2002-308837, and the like.

  In the present invention, in the case of having a plurality of light emitting layers, it is preferable that 50% by mass or more of the host compound in each layer is the same compound because it is easy to obtain a uniform film property over the entire organic layer. It is more preferable that the phosphorescence emission energy of the compound is 2.9 eV or more because it is advantageous in efficiently suppressing energy transfer from the dopant and obtaining high luminance.

  The phosphorescence emission energy as used in the field of this invention means the peak energy of the 0-0 band of the phosphorescence emission which measures the photoluminescence of the vapor deposition film | membrane of 100 nm on a host compound on a board | substrate.

(Dopant)
Next, the dopant will be described.

  There are two types of principles. One is the recombination of carriers on the host to which the carriers are transported to generate an excited state of the host compound, and this energy is transferred to the dopant to obtain light emission from the dopant. The other is the carrier trap type in which the dopant becomes a carrier trap, and carrier recombination occurs on the dopant compound and light emission from the dopant is obtained. In either case, the dopant compound is excited. The condition is that the energy of the state is lower than the energy of the excited state of the host compound.

  The “phosphorescent dopant” and “phosphorescent compound” in the present invention are compounds in which light emission from an excited triplet is observed, and a compound having a phosphorescence quantum yield of 0.001 or more at 25 ° C. The phosphorescence quantum yield is preferably 0.01 or more, more preferably 0.1 or more.

  The phosphorescence quantum yield can be measured by the method described in Spectroscopic II, page 398 (1992 edition, Maruzen) of Experimental Chemistry Course 4 of the 4th edition. Although the phosphorescence quantum yield in a solution can be measured using various solvent, the phosphorescence dopant used for this invention should just achieve the said phosphorescence quantum yield in any solvent.

  The phosphorescent dopant used in the present invention is preferably a complex compound containing a group 8 metal in the periodic table of elements, more preferably an iridium compound, an osmium compound, or a platinum compound (platinum complex compound) ), Rare earth complexes, and most preferred are iridium compounds.

  In the organic EL device of the present invention, the excited triplet energy of all materials of the host compound of the light emitting layer, the hole transport layer adjacent to the light emitting layer, and the electron transport layer adjacent to the light emitting layer is the excited triplet of the phosphorescent dopant. It is preferably larger than the term energy. In particular, the wavelength of the 0-0 band in the phosphorescence spectrum of the host compound of the light emitting layer, the hole transport layer adjacent to the light emitting layer, and the electron transport layer adjacent to the light emitting layer is preferably 450 nm or less.

  The light emission color of the organic EL device of the present invention and the compound according to the present invention is shown in FIG. 4.16 on page 108 of “New Color Science Handbook” (edited by the Japan Color Society, University of Tokyo Press, 1985). It is determined by the color when the result measured with the total CS-1000 (manufactured by Konica Minolta Sensing) is applied to the CIE chromaticity coordinates.

The white element referred to in the present invention means that the chromaticity in the CIE 1931 color system at 1000 Cd / m ² is X = 0.33 ± 0.07 when the front luminance at 2 ° viewing angle is measured by the above method. It is in the region of Y = 0.33 ± 0.07.

  The light emitting layer can be formed by forming the above compound by a known thinning method such as a vacuum deposition method, a spin coating method, a casting method, an LB method, or an ink jet method.

  In the present invention, the light emitting layer includes layers having different emission spectra in which the emission maximum wavelengths are in the range of 430 to 480 nm, 510 to 550 nm, and 600 to 640 nm, or a layer in which these are laminated.

  There is no restriction | limiting in particular as a lamination order of a light emitting layer, You may have a nonluminous intermediate | middle layer between each light emitting layer. In the present invention, it is preferable that at least one blue light emitting layer is provided at a position closest to the anode among all the light emitting layers.

  When four or more light emitting layers are provided, for example, blue / green / red / blue, blue / green / red / blue / green, blue / green / red / blue / green / red in order from the anode. In order to improve luminance stability, it is preferable to sequentially stack blue, green, and red.

  The total film thickness of the light emitting layer is not particularly limited, but is usually 2 nm to 5 μm, preferably 2 to 200 nm. In the present invention, it is preferably in the range of 10 to 20 nm. If it is too thin, it is difficult to obtain film uniformity. If it is thicker than this, a high voltage is required to obtain light emission, which is not preferable. A film thickness of 20 nm or less is preferable because it has the effect of improving the stability of the emission color with respect to the driving current as well as the voltage surface.

  The film thickness of each light emitting layer is preferably selected in the range of 2 to 100 nm, and more preferably in the range of 2 to 20 nm. Although there is no restriction | limiting in particular about the film thickness relationship of each light emitting layer of blue, green, and red, It is preferable that the blue light emitting layer (the sum total when there are two or more layers) is the thickest among three light emitting layers.

  Moreover, in the range which maintains the said maximum wavelength, you may mix a several luminescent compound in each light emitting layer. For example, a blue light emitting compound having a maximum wavelength of 430 to 480 nm and a green light emitting compound having the same wavelength of 510 to 550 nm may be mixed in the blue light emitting layer.

<Support substrate>
The support substrate (hereinafter also referred to as substrate, support, etc.) that can be used in the organic EL device of the present invention is not particularly limited in the type of glass, plastic, etc. Also, it is transparent or opaque. May be. When extracting light from the support substrate side, the support substrate is preferably transparent. Examples of the transparent support substrate preferably used include glass, quartz, and a transparent resin film. A particularly preferable support substrate is a resin film capable of giving flexibility to the organic EL element.

  Examples of the resin film include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyethylene, polypropylene, cellophane, cellulose diacetate, cellulose triacetate, cellulose acetate butyrate, cellulose acetate propionate (CAP), Cellulose esters such as cellulose acetate phthalate (TAC) and cellulose nitrate or derivatives thereof, polyvinylidene chloride, polyvinyl alcohol, polyethylene vinyl alcohol, syndiotactic polystyrene, polycarbonate, norbornene resin, polymethylpentene, polyether ketone, polyimide , Polyethersulfone (PES), polyphenylene sulfide, polysulfones Cycloolefin resins such as polyetherimide, polyetherketoneimide, polyamide, fluororesin, nylon, polymethylmethacrylate, acrylic or polyarylate, Arton (trade name, manufactured by JSR) or Appel (trade name, manufactured by Mitsui Chemicals) Can be mentioned.

The surface of the resin film may be formed with an inorganic film, an organic film, or a hybrid film of both, and is preferably a barrier film having a water vapor transmission rate of 0.01 g / m ² / day · atm or less. Furthermore, a high barrier film having an oxygen permeability of 10 ⁻³ g / m ² / day or less and a water vapor permeability of 10 ⁻⁵ g / m ² / day or less is preferable.

  As a material for forming the barrier film, any material may be used as long as it has a function of suppressing intrusion of elements such as moisture and oxygen, and silicon oxide, silicon dioxide, silicon nitride, and the like can be used. Further, in order to improve the brittleness of the film, it is more preferable to have a laminated structure of these inorganic layers and organic material layers. Although there is no restriction | limiting in particular about the lamination | stacking order of an inorganic layer and an organic layer, It is preferable to laminate | stack both alternately several times.

  The method for forming the barrier film is not particularly limited. For example, vacuum deposition, sputtering, reactive sputtering, molecular beam epitaxy, cluster ion beam method, ion plating method, plasma polymerization method, atmospheric pressure plasma A polymerization method, a plasma CVD method, a laser CVD method, a thermal CVD method, a coating method, or the like can be used, but an atmospheric pressure plasma polymerization method as described in JP-A-2004-68143 is particularly preferable.

  Examples of the opaque support substrate include metal plates such as aluminum and stainless steel, films, opaque resin substrates, and ceramic substrates.

  The external extraction efficiency at room temperature of light emission of the organic EL device of the present invention is preferably 1% or more, more preferably 5% or more. Here, external extraction quantum efficiency (%) = (number of photons emitted to the outside of the organic EL element / number of electrons sent to the organic EL element) × 100.

  In addition, a hue improvement filter such as a color filter may be used in combination, or a color conversion filter that converts the emission color from the organic EL element into multiple colors using a phosphor. In the case of using a color conversion filter, the λmax of light emission of the organic EL element is preferably 480 nm or less.

<Sealing>
As a sealing means used for this invention, the method of adhere | attaching a sealing member, an electrode, and a support substrate with an adhesive agent can be mentioned, for example.

  As a sealing member, it should just be arrange | positioned so that the display area | region of an organic EL element may be covered, and concave plate shape or flat plate shape may be sufficient. Further, transparency and electrical insulation are not particularly limited.

Specific examples include a glass plate, a polymer plate / film, and a metal plate / film. Examples of the glass plate include soda-lime glass, barium / strontium-containing glass, lead glass, aluminosilicate glass, borosilicate glass, barium borosilicate glass, and quartz. Examples of the polymer plate include polycarbonate, acrylic, polyethylene terephthalate, polyether sulfide, and polysulfone. Examples of the metal plate include those made of one or more metals or alloys selected from the group consisting of stainless steel, iron, copper, aluminum, magnesium, nickel, zinc, chromium, titanium, molybdenum, silicon, germanium, and tantalum. In the present invention, a polymer film and a metal film can be preferably used because the element can be thinned. Furthermore, the polymer film preferably has an oxygen permeability of 10 ⁻³ g / m ² / day or less and a water vapor permeability of 10 ⁻⁵ g / m ² / day or less.

  For processing the sealing member into a concave shape, sandblasting, chemical etching, or the like is used.

  Specific examples of the adhesive include photocuring and thermosetting adhesives having reactive vinyl groups such as acrylic acid oligomers and methacrylic acid oligomers, and moisture curing adhesives such as 2-cyanoacrylates. be able to. Moreover, heat | fever and chemical curing types (two-component mixing), such as an epoxy type, can be mentioned. Moreover, hot-melt type polyamide, polyester, and polyolefin can be mentioned. Moreover, a cationic curing type ultraviolet curing epoxy resin adhesive can be mentioned.

  In addition, since an organic EL element may deteriorate by heat processing, what can be adhesive-hardened from room temperature to 80 degreeC is preferable. A desiccant may be dispersed in the adhesive. Application | coating of the adhesive agent to a sealing part may use commercially available dispenser, and may print like screen printing.

  In addition, it is also preferable that the electrode and the organic layer are coated on the outside of the electrode facing the support substrate with the organic layer interposed therebetween, and an inorganic or organic layer is formed in contact with the support substrate to form a sealing film. . In this case, as a material for forming the film, any material may be used as long as it has a function of suppressing the intrusion of elements such as moisture and oxygen. For example, silicon oxide, silicon dioxide, silicon nitride, or the like is used. it can. Further, in order to improve the brittleness of the film, it is preferable to have a laminated structure of these inorganic layers and layers made of organic materials. The method for forming these films is not particularly limited. For example, vacuum deposition method, sputtering method, reactive sputtering method, molecular beam epitaxy method, cluster ion beam method, ion plating method, plasma polymerization method, atmospheric pressure A plasma polymerization method, a plasma CVD method, a laser CVD method, a thermal CVD method, a coating method, or the like can be used.

  In the gap between the sealing member and the display area of the organic EL element, an inert gas such as nitrogen or argon, an inert liquid such as fluorinated hydrocarbon, or silicon oil can be injected in the gas phase and liquid phase. preferable. A vacuum can also be used. Moreover, a hygroscopic compound can also be enclosed inside.

  Examples of the hygroscopic compound include metal oxides (for example, sodium oxide, potassium oxide, calcium oxide, barium oxide, magnesium oxide, aluminum oxide) and sulfates (for example, sodium sulfate, calcium sulfate, magnesium sulfate, cobalt sulfate). Etc.), metal halides (eg calcium chloride, magnesium chloride, cesium fluoride, tantalum fluoride, cerium bromide, magnesium bromide, barium iodide, magnesium iodide etc.), perchloric acids (eg perchloric acid) Barium, magnesium perchlorate, and the like), and anhydrous salts are preferably used in sulfates, metal halides, and perchloric acids.

<Protective film, protective plate>
In order to increase the mechanical strength of the element, a protective film or a protective plate may be provided outside the sealing film or the sealing film on the side facing the support substrate with the organic layer interposed therebetween. In particular, when sealing is performed by the sealing film, the mechanical strength is not necessarily high, and thus it is preferable to provide such a protective film and a protective plate. As a material that can be used for this, the same glass plate, polymer plate / film, metal plate / film, and the like used for the sealing can be used, but the polymer film is light and thin. Is preferably used.

<Light extraction>
The organic EL element emits light inside a layer having a refractive index higher than that of air (refractive index is about 1.7 to 2.1) and can extract only about 15 to 20% of the light generated in the light emitting layer. Is generally said. This is because light incident on the interface (interface between the transparent substrate and air) at an angle θ greater than the critical angle causes total reflection and cannot be taken out of the device, or between the transparent electrode or light emitting layer and the transparent substrate. This is because the light is totally reflected between the light and the light is guided through the transparent electrode or the light emitting layer, and as a result, the light escapes in the direction of the element side surface.

  As a method for improving the light extraction efficiency, for example, a method of forming irregularities on the surface of the transparent substrate to prevent total reflection at the interface between the transparent substrate and the air (US Pat. No. 4,774,435), A method of improving efficiency by providing a light collecting property to a substrate (Japanese Patent Laid-Open No. 63-314795), a method of forming a reflective surface on a side surface of an element (Japanese Patent Laid-Open No. 1-220394), and light emission from a substrate A method of forming an antireflection film by introducing a flat layer having an intermediate refractive index between the bodies (Japanese Patent Laid-Open No. 62-172691), a flat having a lower refractive index between the substrate and the light emitter than the substrate A method of introducing a layer (Japanese Patent Laid-Open No. 2001-202827), a method of forming a diffraction grating between any one of a substrate, a transparent electrode layer and a light emitting layer (including between the substrate and the outside) (Japanese Patent Laid-Open No. 11-283951) Gazette).

  In the present invention, these methods can be used in combination with the organic EL device of the present invention. However, a method of introducing a flat layer having a lower refractive index than the substrate between the substrate and the light emitter, or a substrate, transparent A method of forming a diffraction grating between any layers of the electrode layer and the light emitting layer (including between the substrate and the outside) can be suitably used.

  In the present invention, by combining these means, it is possible to obtain an element having higher luminance or durability.

  When a medium having a low refractive index is formed between the transparent electrode and the transparent substrate with a thickness longer than the wavelength of light, the light extracted from the transparent electrode has a higher extraction efficiency to the outside as the refractive index of the medium is lower.

  Examples of the low refractive index layer include aerogel, porous silica, magnesium fluoride, and a fluorine-based polymer. Since the refractive index of the transparent substrate is generally about 1.5 to 1.7, the low refractive index layer preferably has a refractive index of about 1.5 or less. Further, it is preferably 1.35 or less.

  The thickness of the low refractive index medium is preferably at least twice the wavelength in the medium. This is because the effect of the low refractive index layer is diminished when the thickness of the low refractive index medium is about the wavelength of light and the electromagnetic wave that has exuded by evanescent enters the substrate.

  The method of introducing a diffraction grating into an interface or any medium that causes total reflection is characterized by a high effect of improving light extraction efficiency. This method uses the property that the diffraction grating can change the direction of light to a specific direction different from refraction by so-called Bragg diffraction such as first-order diffraction and second-order diffraction. Of these, light that cannot be emitted due to total reflection between layers, etc. is diffracted by introducing a diffraction grating into any layer or medium (inside a transparent substrate or transparent electrode). Is going to be taken out.

  The introduced diffraction grating desirably has a two-dimensional periodic refractive index. This is because light emitted from the light-emitting layer is randomly generated in all directions, so in a general one-dimensional diffraction grating having a periodic refractive index distribution only in a certain direction, only light traveling in a specific direction is diffracted. The light extraction efficiency does not increase so much. However, by making the refractive index distribution a two-dimensional distribution, light traveling in all directions is diffracted, and light extraction efficiency is increased.

  As described above, the position where the diffraction grating is introduced may be in any of the layers or in the medium (in the transparent substrate or the transparent electrode), but is preferably in the vicinity of the organic light emitting layer where light is generated.

  At this time, the period of the diffraction grating is preferably about 1/2 to 3 times the wavelength of light in the medium.

  The arrangement of the diffraction grating is preferably two-dimensionally repeated, such as a square lattice, a triangular lattice, or a honeycomb lattice.

<Condensing sheet>
The organic EL device of the present invention is processed on the light extraction side of the substrate so as to provide, for example, a microlens array structure, or combined with a so-called condensing sheet, for example, with respect to a specific direction, for example, the device light emitting surface. By condensing in the front direction, the luminance in a specific direction can be increased.

  As an example of the microlens array, quadrangular pyramids having a side of 30 μm and an apex angle of 90 degrees are two-dimensionally arranged on the light extraction side of the substrate. One side is preferably 10 to 100 μm. If it becomes smaller than this, the effect of diffraction will generate | occur | produce and color, and if too large, thickness will become thick and is not preferable.

  As the condensing sheet, for example, a sheet that is put into practical use in an LED backlight of a liquid crystal display device can be used. As such a sheet, for example, a brightness enhancement film (BEF) manufactured by Sumitomo 3M Limited can be used. As the shape of the prism sheet, for example, a triangle stripe having a vertex angle of 90 degrees and a pitch of 50 μm may be formed on the substrate, the vertex angle may be rounded, and the pitch may be changed randomly. Other shapes may be used.

  Moreover, in order to control the light emission angle from a light emitting element, you may use together a light diffusing plate and a film with a condensing sheet. For example, a diffusion film (light-up) manufactured by Kimoto Co., Ltd. can be used.

<Method for producing organic EL element>
As an example of the method for producing the organic EL device of the present invention, a method for producing an organic EL device comprising an anode / hole injection layer / hole transport layer / light emitting layer / electron transport layer / electron injection layer / cathode will be described.

  First, a thin film made of a desired electrode material, for example, a material for an anode is formed on a suitable substrate by a method such as vapor deposition or sputtering so as to have a film thickness of 1 μm or less, preferably 10 to 200 nm to produce an anode. .

  Next, an organic compound thin film of a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, an electron injection layer, and a hole blocking layer, which are organic EL element materials, is formed thereon.

  As a method for thinning the organic compound thin film, there are a vapor deposition method and a wet process (spin coating method, casting method, ink jet method, printing method) as described above, but it is easy to obtain a uniform film and a pinhole. In the present invention, film formation by a coating method such as a spin coating method, an ink jet method, or a printing method is particularly preferable.

  In the present invention, in forming the light emitting layer, it is preferable to form a film by a coating method using a solution in which the compound represented by the general formula (1) according to the present invention is dissolved or dispersed, and the coating method is particularly an inkjet method. It is preferable that

  Examples of the liquid medium for dissolving or dispersing the compound represented by the general formula (1) according to the present invention include ketones such as methyl ethyl ketone and cyclohexanone, fatty acid esters such as ethyl acetate, and halogenated hydrocarbons such as dichlorobenzene. Organic solvents such as DMF and DMSO can be used. Moreover, as a dispersion method, it can disperse | distribute by dispersion methods, such as an ultrasonic wave, high shear force dispersion | distribution, and media dispersion | distribution.

  After forming these layers, a thin film made of a cathode material is formed thereon by a method such as vapor deposition or sputtering so as to have a thickness of 1 μm or less, preferably 50 to 200 nm, and a cathode is provided. A desired organic EL element is obtained.

  In addition, it is also possible to reverse the production order and produce the cathode, the electron injection layer, the electron transport layer, the light emitting layer, the hole transport layer, the hole injection layer, and the anode in this order. When a DC voltage is applied to the multicolor display device thus obtained, light emission can be observed by applying a voltage of about 2 to 40 V with the positive polarity of the anode and the negative polarity of the cathode. An alternating voltage may be applied. The alternating current waveform to be applied may be arbitrary.

<Application>
The organic EL element of the present invention can be used as a display device or a lighting device.

<Display device>
The display device of the present invention will be described. The display device of the present invention has the organic EL element.

  Although the display device of the present invention may be single color or multicolor, the multicolor display device will be described here. In the case of a multicolor display device, a shadow mask is provided only at the time of forming a light emitting layer, and a film can be formed on one surface by vapor deposition, casting, spin coating, ink jet, printing, or the like.

  When patterning is performed only on the light-emitting layer, the method is not limited, but a vapor deposition method, an inkjet method, and a printing method are preferable. In the case of using a vapor deposition method, patterning using a shadow mask is preferable.

  When a DC voltage is applied to the multicolor display device thus obtained, light emission can be observed by applying a voltage of about 2 to 40 V with the positive polarity of the anode and the negative polarity of the cathode. Further, even when a voltage is applied with the opposite polarity, no current flows and no light emission occurs. Further, when an AC voltage is applied, light is emitted only when the anode is in the + state and the cathode is in the-state. The alternating current waveform to be applied may be arbitrary.

  The multicolor display device can be used as a display device, a display, and various light emission sources. In a display device or display, full-color display is possible by using three types of organic EL elements of blue, red, and green light emission.

  Examples of the display device and display include a television, a personal computer, a mobile device, an AV device, a character broadcast display, and an information display in an automobile. In particular, it may be used as a display device for reproducing still images and moving images, and the driving method when used as a display device for reproducing moving images may be either a simple matrix (passive matrix) method or an active matrix method.

  Light sources include home lighting, interior lighting, clock and liquid crystal backlights, billboard advertisements, traffic lights, light sources for optical storage media, light sources for electrophotographic copying machines, light sources for optical communication processors, light sources for optical sensors, etc. For example, it is not limited to this.

《Lighting device》
The lighting device of the present invention will be described. The illumination device of the present invention has the organic EL element.

  The organic EL element of the present invention may be used as an organic EL element having a resonator structure. The purpose of use of the organic EL element having such a resonator structure is as follows. The light source of a machine, the light source of an optical communication processing machine, the light source of a photosensor, etc. are mentioned, However, It is not limited to these. Moreover, you may use for the said use by making a laser oscillation.

  Further, the organic EL element of the present invention may be used as a kind of lamp for illumination or exposure light source, a projection device for projecting an image, or a display for directly viewing a still image or a moving image. It may be used as a device (display). The driving method when used as a display device for moving image reproduction may be either a simple matrix (passive matrix) method or an active matrix method. Alternatively, a full-color display device can be manufactured by using two or more organic EL elements of the present invention having different emission colors.

  As described above, the organic EL element according to the present invention is not only the display device and the display, but also various light emitting sources, lighting devices, household lighting, interior lighting, a kind of lamp such as an exposure light source, and liquid crystal. It is also useful for display devices such as backlights for display devices.

  Others such as backlights for watches, signboard advertisements, traffic lights, light sources for optical storage media, light sources for electrophotographic copying machines, light sources for optical communication processors, light sources for optical sensors, etc. There are a wide range of uses such as household appliances.

  In the organic EL device of the present invention, patterning may be performed by a metal mask, an ink jet printing method, or the like at the time of film formation, if necessary. When patterning, only the electrode may be patterned, the electrode and the light emitting layer may be patterned, or the entire element layer may be patterned.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. In addition, although the display of "part" or "%" is used in an Example, unless otherwise indicated, "part by mass" or "mass%" is represented.

<Synthesis example>
(Synthesis of Exemplified Compound 1)
Exemplary compound 1 can be synthesized according to the following scheme.

Compound A was obtained in 90% yield by heating and refluxing carbazole and 1-fluoro-2-nitrobenzene for 1 hour in the presence of potassium carbonate. Compound A was reduced with tin powder and converted to compound B in 91% yield. Compound B was reacted with sodium nitrite at 0 ° C. in a sulfuric acid (concentration: 18% by volume) and acetic acid (concentration: 82% by volume) solvent, and then condensed by thermal decomposition to obtain Compound C in a yield of 62%. Compound C was brominated with N-bromosuccinimide in DMF to obtain Compound D in a yield of 56%. Compound D was reacted with bispinacolatodiborane and potassium carbonate to obtain Compound E in a yield of 50%. Compound E and 2,7-dibromonaphthalene were reacted in DMSO to obtain Exemplified Compound 1 in a yield of 55%. The structure of Exemplified Compound 1 was confirmed by ¹ H-NMR spectrum and MS spectrum. PdCl ₂ (dppf) represents 1,1-bis (diphenylphosphinoferrocene) palladium dichloride.

  (Synthesis of Exemplified Compound 7)

The compound E and 3,7-dibromobenzofuran were reacted in DMSO to obtain Exemplary Compound 7 at 60%. The structure of Exemplified Compound 7 was confirmed by ¹ H-NMR spectrum and MS spectrum.

  (Synthesis of Exemplified Compound 47)

The compound E was reacted with 8-bromo-1,5-diphenyldibenzoborol in DMSO to obtain 64% of Exemplified Compound 47. The structure of Exemplified Compound 47 was determined by ¹ H-NMR spectrum and MS spectrum. confirmed.

  (Synthesis of Exemplary Compound 81)

The compound E and 6-bromo-2-iodo-5,5-diphenyldibenzosilole were reacted in DMSO to obtain Exemplified Compound 81 at 53%. The structure of exemplary compound 81 was confirmed by ¹ H-NMR spectrum and MS spectrum.

  (Synthesis of Exemplary Compound 100)

The compound E and 6-bromo-2-iododibenzofuran were reacted in DMSO to obtain Exemplary Compound 100 at 53%. The structure of exemplary compound 100 was confirmed by ¹ H-NMR spectrum and MS spectrum.

Example 1
<Preparation of Organic EL Element 1-1>
Transparent support provided with this ITO transparent electrode after patterning on a substrate (NH45 manufactured by NH Techno Glass) made of ITO (indium tin oxide) with a thickness of 100 nm on a glass substrate of 100 mm × 100 mm × 1.1 mm as an anode The substrate was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and subjected to UV ozone cleaning for 5 minutes. This transparent support substrate is fixed to a substrate holder of a commercially available vacuum evaporation apparatus, while 200 mg of α-NPD is placed in a molybdenum resistance heating boat as a hole transport material as a host compound for comparison with another resistance heating boat made of molybdenum. 200 mg of A-1 was added, 100 mg of Ir (ppy) ₃ as a luminescent dopant was put in another resistance heating boat made of molybdenum, and 200 mg of Alq ₃ was put in another resistance heating boat made of molybdenum as an electron injection material. Installed on.

Next, after the pressure in the vacuum chamber was reduced to 4 × 10 ⁻⁴ Pa, the heating boat containing α-NPD was energized and heated, and deposited on the transparent support substrate at a deposition rate of 0.1 nm / sec. The hole transport layer was provided. Further, the heating boat containing A-1 and Ir (ppy) ₃ was energized and heated, and co-deposited on the hole transport layer at a deposition rate of 0.2 nm / sec and 0.012 nm / sec, respectively. A light emitting layer having a thickness of 40 nm was provided. Further, the heating boat containing Alq ₃ was further energized and heated, and deposited on the light emitting layer at a deposition rate of 0.1 nm / sec, and an electron injection layer having a thickness of 40 nm was further provided. In addition, the substrate temperature at the time of vapor deposition was room temperature.

  Then, 0.5 nm of lithium fluoride and 110 nm of aluminum were vapor-deposited, the cathode was formed, and the organic EL element 1-1 was produced.

The structures of Alq _{3 as} an electron transport material, α-NPD as a hole transport material, and Ir (ppy) ₃ as a light-emitting dopant are shown below.

(Preparation of organic EL elements 1-2 to 1-23)
In the production of the organic EL element 1-1, the organic EL element was similarly prepared except that the host compound was changed to the comparative compounds A-2 to A-5 and the exemplified compound according to the present invention as shown in Table 1. 1-2 to 1-23 were produced.

<Evaluation of organic EL element>
The non-light-emitting surface of each organic EL element after fabrication is covered with a glass case, a 300 μm thick glass substrate is used as a sealing substrate, and an epoxy photo-curing adhesive (LUX Track LC0629B) is applied, and this is overlaid on the cathode and brought into close contact with the transparent support substrate, irradiated with UV light from the glass substrate side, cured, and sealed, as shown in FIGS. Such a lighting device was formed and evaluated.

  FIG. 1 is a schematic view showing an example of a lighting device using the organic EL element of the present invention, and shows a case where emitted light 7 is extracted in a white arrow direction (downward). The organic EL element 101 is covered with a glass cover 102 (in addition, the sealing operation with the glass cover is performed in a glove box (purity of 99.999% or more in a nitrogen atmosphere without bringing the organic EL element 101 into contact with the atmosphere). Performed in an atmosphere of high-purity nitrogen gas). FIG. 2 is a cross-sectional view showing an example of a lighting device using the organic EL element of the present invention. In FIG. 2, 105 denotes a cathode, 106 denotes an organic EL layer, and 107 denotes a glass substrate with a transparent electrode. The glass cover 102 is filled with nitrogen gas 108 and a water catching agent 109 is provided.

(External quantum efficiency)
About the produced organic EL element, external extraction quantum efficiency (%) when ^2.5 mA / cm ² constant current was applied in a dry nitrogen gas atmosphere at 23 ° C. was measured. For the measurement, a spectral radiance meter CS-1000 (manufactured by Konica Minolta Sensing) was used.

  The measurement results of the external extraction quantum efficiency in Table 1 are expressed as relative values when the measurement value of the organic EL element 1-1 is 100.

(Luminescent life)
When driven at a constant current of ^2.5 mA / cm ² , the time required for the luminance to drop to half of the luminance immediately after the start of light emission (initial luminance) was measured, and this was calculated as the half-life time (τ 0.5). As an index of life. For the measurement, a spectral radiance meter CS-1000 (manufactured by Konica Minolta Sensing) was used.

  Moreover, the measurement result of the lifetime of Table 1 was represented by the relative value when the organic EL element 1-1 was set to 100.

(Drive voltage)
Each element is caused to emit light by applying a DC voltage so that the luminance becomes 1000 cd / m ² . The applied voltage at this time was used as an index for driving voltage evaluation.

  Moreover, the measurement result of Table 1 was represented by the drive voltage difference ((DELTA) V) with the organic EL element 1-1. A lower value (minus) indicates a lower drive voltage, which is preferable.

  The compounds A-1 to A-5 used in the comparative examples are shown below.

  From Table 1, it can be seen that the organic EL device of the present invention containing the compound of the present invention in the host compound of the light emitting layer has achieved high efficiency, low voltage drive and long life.

Example 2
<Preparation of organic EL element 2-1>
Transparent support provided with this ITO transparent electrode after patterning on a substrate (NH45 manufactured by NH Techno Glass) made of ITO (indium tin oxide) with a thickness of 100 nm on a glass substrate of 100 mm × 100 mm × 1.1 mm as an anode The substrate was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and subjected to UV ozone cleaning for 5 minutes. This transparent support substrate is fixed to a substrate holder of a commercially available vacuum evaporation apparatus, while 200 mg of α-NPD is placed in a molybdenum resistance heating boat as a hole transport material as a host compound for comparison with another resistance heating boat made of molybdenum. 200 mg of A-1 is put, 200 mg of A-1 is put into another molybdenum resistance heating boat as a comparative electron transport material, 100 mg of Ir (ppy) ₃ is put as a luminescent dopant in another resistance heating boat made of molybdenum, and In another resistance heating boat made of molybdenum, 200 mg of Alq ₃ was placed as an electron injection material, and attached to a vacuum deposition apparatus.

Next, after the pressure in the vacuum chamber was reduced to 4 × 10 ⁻⁴ Pa, the heating boat containing α-NPD was energized and heated, and deposited on the transparent support substrate at a deposition rate of 0.1 nm / sec. The hole transport layer was provided. Further, the heating boat containing A-1 and Ir (ppy) ₃ was energized and heated, and co-deposited on the hole transport layer at a deposition rate of 0.2 nm / sec and 0.012 nm / sec, respectively. A light emitting layer having a thickness of 40 nm was provided. In addition, the substrate temperature at the time of vapor deposition was room temperature. Further, an electron transport layer having a thickness of 10 nm which also serves as a hole blocking layer is formed by energizing and heating the heating boat containing A-1 and vapor-depositing the light-emitting layer at a deposition rate of 0.1 nm / sec. Provided. On top of this, the heating boat containing Alq ₃ was further energized and heated, and deposited on the electron transport layer at a deposition rate of 0.1 nm / sec, and an electron injection layer having a thickness of 40 nm was further provided. . In addition, the substrate temperature at the time of vapor deposition was room temperature. Then, 0.5 nm of lithium fluoride and 110 nm of aluminum were vapor-deposited, the cathode was formed, and the organic EL element 2-1 was produced.

(Preparation of organic EL elements 2-2 to 2-14)
In the production of the organic EL element 2-1, as described in Table 2, the organic EL element 2 was similarly obtained except that the host compound and the electron transporting material were changed from the comparative A-1 to the exemplified compound according to the present invention. −2 to 2-14 were produced.

  Similar to the measurement in Table 1, the illumination devices of FIGS. 1 and 2 were formed, and the external quantum efficiency, the drive voltage difference (ΔV), and the light emission lifetime were measured according to the organic EL element No. Measurement was performed with reference to 2-1. The measurement results are summarized in Table 2 below.

  From Table 2, it can be seen that the organic EL device of the present invention containing the compound of the present invention in the host compound of the electron transport layer and the light emitting layer has achieved high efficiency, low voltage drive and long life.

Example 3
<Preparation of organic EL element 3-1>
Transparent support provided with this ITO transparent electrode after patterning on a substrate (NH45 manufactured by NH Techno Glass) made of ITO (indium tin oxide) with a thickness of 100 nm on a glass substrate of 100 mm × 100 mm × 1.1 mm as an anode The substrate was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and subjected to UV ozone cleaning for 5 minutes. This transparent support substrate is fixed to a substrate holder of a commercially available vacuum evaporation apparatus, while 200 mg of A-1 is added as a comparative hole transport material to a resistance heating boat made of molybdenum, and as a host compound in another resistance heating boat made of molybdenum. 200 mg of comparative A-3 was added, 100 mg of Ir (ppy) ₃ was added as a luminescent dopant to another molybdenum resistance heating boat, and 200 mg of Alq ₃ was added as an electron injection material to another resistance heating boat made of molybdenum. Attached to the vapor deposition equipment.

Next, after the pressure in the vacuum chamber was reduced to 4 × 10 ⁻⁴ Pa, the heating boat containing A-1 was energized and heated, and deposited on the transparent support substrate at a deposition rate of 0.1 nm / sec. The hole transport layer was provided. Further, the heating boat containing A-3 and Ir (ppy) ₃ was energized and heated, and co-deposited on the hole transport layer at a deposition rate of 0.2 nm / sec and 0.012 nm / sec, respectively. A light emitting layer having a thickness of 40 nm was provided. Further, the heating boat containing Alq ₃ was further energized and heated, and deposited on the light emitting layer at a deposition rate of 0.1 nm / sec, and an electron injection layer having a thickness of 40 nm was further provided. In addition, the substrate temperature at the time of vapor deposition was room temperature. Then, 0.5 nm of lithium fluoride and 110 nm of aluminum were vapor-deposited, the cathode was formed, and the organic EL element 3-1 was produced.

(Preparation of organic EL elements 3-2 to 3-14)
In the production of the organic EL element 3-1, organic EL elements 3-2 to 3-14 were produced in the same manner except that the host compound and the hole transport material were changed as shown in Table 3.

  Similar to the measurement in Table 1, the illumination devices of FIGS. 1 and 2 were formed, and the external quantum efficiency, the drive voltage difference (ΔV), and the light emission lifetime were measured according to the organic EL element No. Measurement was performed with reference to 3-1. Table 3 below summarizes the measurement results.

  From Table 3, it can be seen that the organic EL device of the present invention containing the compound of the present invention in the host compound of the hole transport layer or the light emitting layer has achieved high efficiency, low voltage drive and long life.

7 Light emitted 101 Organic EL element 102 Glass cover 105 Glass substrate with transparent electrode 106 Organic EL layer 107 Cathode 108 Nitrogen gas 109 Water replenisher

Claims (11)

An organic electroluminescence device having at least one organic layer including a light emitting layer between a pair of electrodes, wherein at least one of the organic layers has a compound represented by the following general formula (1). Organic electroluminescence device.

(In General Formula (1), X represents General Formula (2), and n ₁ represents an integer of ₁ to 4. When n ₁ is 2 or more, each X may be the same or different. In general formula (2), A _{101 to} A ₁₁₁ each represent N or C—R, each R independently represents a hydrogen atom, a substituent or a bond to L ₁ , n ₁ = 2 to 2 In the case of 4, L ₁ represents an aromatic condensed ring or a heteroaromatic condensed ring, and when n ₁ = 1, L ₁ represents a naphthalene ring, anthracene ring, tetracene ring, pyrene ring, phenanthrene ring, phenalene ring, triphenylene Ring, coronene ring, quinoline ring, benzoborol ring, isoindole ring, indole ring, benzofuran ring, phosphinoindole ring, phosphinoindole oxide ring, benzosilol ring, benzothiophene ring, benzodiborol Benzodifuran ring, benzodithiophene ring, benzodisilol ring, dibenzoborol ring, carbazole ring, dibenzofuran ring, benzophosphinoindole ring, dibenzosilole ring and dibenzothiophene ring Represents an aromatic condensed ring, and when the aromatic condensed ring or the heteroaromatic condensed ring has a substituent, the substituents are not connected to form a ring, and L ₁ is a general formula. It is not a skeleton structure represented by (2) L ₁ and X are bonded via a carbon atom constituting L ₁ , provided that the compound is represented by the following general formula (i) Is excluded.)

(In the general formula (i), X represents the general formula (2), Ar ¹ is a 6-membered aromatic ring, which may be substituted by one or more groups R ¹ , and T ¹ is a simple group. Bond, R ¹ represents H or a substituent.) In the general formula (1), an organic electroluminescence device according to claim 1, n ₁ is equal to or an integer of 2-4. Formula (1), an organic electroluminescence device according to claim 1 or 2 L ₁ is characterized in that it is a heteroaromatic fused rings. The organic electroluminescence device according to claim 3, characterized in that in said formula (1), L ₁ is represented by the general formula (3).

(In General Formula (3), A _{201 to} A ₂₀₈ represent N or C—R, and Y ₁ represents O, S, NR ′, BR ′, SiR′R ″, PR ′ or P (Z ₁ ) R ′. R, R ′ and R ″ each independently represents a hydrogen atom, a substituent or a bond, and Z ₁ represents O or S.) Formula (3), an organic electroluminescence device according to claim 4, characterized in that Y ₁ is represented by O or S.   In the general formula (3), R, R ′, and R ″ are represented by a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, an alkynyl group, an aryl group, an aromatic heterocyclic ring, a heterocyclic group, or an alkoxy group. The organic electroluminescent element according to claim 4, wherein The organic electroluminescence device according to claim 6, wherein the compound represented by the general formula (1) is a compound represented by the general formula (4).

(In General Formula (4), A _{301 to} A ₃₃₀ represent N or C—R, and Y ₂ represents O, S, NR ′, BR ′, SiR′R ″, PR ′ or P (Z ₂ ) R. R represents R, R ′ and R ″ each independently represents a hydrogen atom, a substituent or a bond, and Z ₂ represents O or S.) In the compound represented by the general formula (4), Y ₂ is represented by O or S. The organic electroluminescent element according to claim 7. An organic electroluminescence device having at least one organic layer including a light emitting layer between a pair of electrodes, wherein at least one of the organic layers has a compound represented by the following general formula (1). Organic electroluminescence device.

(In General Formula (1), X represents General Formula (2), and n ₁ represents an integer of ₁ to 4. When n ₁ is 2 or more, each X may be the same or different. good. also, in the general formula _{(2), .L 1 a 101} ~A 111 is representative of a bond to each .R is independently a hydrogen atom, a substituent or _{L 1} representing N or C-R are aromatic It represents a condensed ring or a heteroaromatic condensed ring, and is not a skeleton structure represented by the general formula (2) L ₁ and X are bonded via a carbon atom constituting L ₁ . However, the following general formula (ii) , formula (I-29), formula (I-30) , formula (I-44), formula (I-45), formula (I-49), formula (I-50) And the compounds represented by formula (I-54) and formula (I-55) are excluded.)

(In general formula (ii), X is as defined in general formula (2);
T ¹ , T ² , T ³ are single bonds;
Ar ¹ is an aromatic ring system having 6 aromatic ring atoms, which may be substituted by one or more groups R ¹ ;
R ¹ is the same or different every time it appears, and H, D, F, Cl, Br, I, CHO, N (R ³ ) ₂ , C (═O) R ³ , P (═O) (R ³ ) ₂ , S (= O) R ³ , S (= O) ₂ R ³ , CR ³ = C (R ³ ) ₂ , CN, NO ₂ , Si (R ³ ) ₃ , B (OR ³ ) ₂ , OSO ₂ R ³ , OH, a linear alkyl group having 1 to 40 C atoms, an alkoxy group or a thioalkyl group, or a branched or cyclic alkyl group having 3 to 40 C atoms, an alkoxy group or a thioalkyl group, or An alkenyl or alkynyl group having 2 to 40 C atoms, each of which may be substituted by one or more groups R ³ , wherein one or more non-adjacent CH ₂ groups are R ^{3 C = CR 3, C≡C, Si} (R 3) 2, _{^{e (R 3) 2, Sn}} (R 3) 2, C = O, C = S, C = Se, C = NR 3, P (= O) (R 3), SO, SO 2, NR 3, O , S or CONR ³ , one or more H atoms may be replaced by D, F, Cl, Br, I, CN, or NO ₂ ), or 5-60 A monocyclic or polycyclic aromatic ring system or heteroaromatic ring system having 5 aromatic ring atoms, which in each case may be substituted by one or more non-aromatic groups R ³ , or 5 An aryloxy or heteroaryloxy group having ˜60 aromatic ring atoms (which may be substituted by one or more non-aromatic groups R ³ ), or a combination of these systems, Two or more groups R ¹ are connected to each other May form a monocyclic or polycyclic aliphatic ring system or an aromatic ring system;
R ³ is the same or different every time it appears, and H, D, F, Cl, Br, I, CHO, N (R ⁴ ) 2, C (═O) R ⁴ , P (═O) (R ⁴ ) ₂ , S (= O) R ⁴ , S (= O) ₂ R ⁴ , CR ⁴ = C (R ⁴ ) ₂ , CN, NO ₂ , Si (R ⁴ ) ₃ , B (OR ⁴ ) ₂ , OSO ₂ R ⁴ , OH, a linear alkyl group having 1 to 40 C atoms, an alkoxy group or a thioalkyl group, or a branched or cyclic alkyl group having 3 to 40 C atoms, an alkoxy group or a thioalkyl group, or An alkenyl or alkynyl group having 2 to 40 C atoms, each of which may be substituted by one or more groups R ⁴ , wherein one or more non-adjacent CH ₂ groups are ^{R 4 C = CR 4, C≡C} , Si (R 4) 2 _{^{Ge (R 4) 2, Sn}} (R 4) 2, C = O, C = S, C = Se, C = NR 4, P (= O) (R 4), SO, SO 2, NR 4, O , S or CONR ⁴ and one or more H atoms may be replaced by D, F, Cl, Br, I, CN, or NO ₂ ), or 5-60 A monocyclic or polycyclic aromatic ring system or heteroaromatic ring system having 5 aromatic ring atoms, which in each case may be substituted by one or more non-aromatic groups R ⁴ , or 5 An aryloxy or heteroaryloxy group having ˜60 aromatic ring atoms (which may be substituted by one or more non-aromatic groups R ⁴ ), or a combination of these systems, two or more radicals ^{R 3} are communicated with each other May also be, they may form a monocyclic or polycyclic aliphatic ring systems or aromatic ring system;
R ⁴ is the same or different for each occurrence and is an aliphatic, aromatic and / or heteroaromatic organic group having 1 to 20 C atoms, wherein H, D, F or 1 H atom may be replaced by D or F), wherein two or more identical or different substituents R ⁴ may also be linked to each other, monocyclic or polycyclic May form an aliphatic ring system or an aromatic ring system;
m1, m2, m3 are the same or different at each occurrence and are 0 or 1, where when m1, m2 or m3 = 0, the radical R ¹ is a radical of the radical T ¹ , T ² or T ³ , respectively. Instead combined;
p is equal to 1. )

( Formula (I-29), Formula (I-30), Formula (I-44), Formula (I-45), Formula (I-49), Formula (I-50), Formula (I-54) and In formula (I-55) , L is the same or different each time it appears, and BR ² , C (R ² ) ₂ , R ² C═CR ² , Si (R ² ) ₂ , C═O, C═NR Selected from ² , O, S, SO, SO ₂ , PR ² , POR ² and NR ² ;
R ¹ is as defined in general formula (ii);
R ² has the same meaning as R ¹ in formula (ii). )   A display device using the organic electroluminescence element according to claim 1.   An illuminating device using the organic electroluminescence element according to any one of claims 1 to 9.

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