JP2009114068A - Triphenylene compound and organic light-emitting device by using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic light-emitting material having a good light-emitting efficiency, especially a triphenylene compound capable of being used together with a blue color light-emitting material, blue-green color-light-emitting material or red color light-emitting material. <P>SOLUTION: By using the triphenylene compound bonded with a fluorene unit or a carbazole unit as a constituting material of the organic light-emitting element, it is possible to obtain stable emitted light having a high efficiency, originated from the characteristics of the triphenylene compound. Especially, in the case of forming a light-emitting layer by using a phosphorescent light-emitting material as a guest and the triphenylene compound as a host, it is possible to obtain the organic light-emitting element having a high electric field light-emitting efficiency by utilizing a high T1 level of the triphenylene compound. Also, in the case of using the triphenylene compound as the constituting material of an adjacent layer to a layer containing the phosphorescent light-emitting material, it is possible to obtain the organic light-emitting element having a high electric field light-emitting efficiency by utilizing the high T1 level of the triphenylene compound. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a triphenylene compound and an organic light emitting device using the same.

  In recent years, research and development of organic electroluminescence devices has been extensively and vigorously performed. In particular, recently, as disclosed in Non-Patent Document 1, for example, phosphorescent organic electroluminescent elements are actively studied from the viewpoint of luminous efficiency.

Here, in order to maximize the luminous efficiency of the phosphorescent organic electroluminescent device, the lowest excited triplet energy (T ₁ ) of the phosphorescent material is higher than T ₁ of the host material and the organic compound in the adjacent layer. It is necessary to make it sufficiently high (see Non-Patent Document 1 and Patent Document 1).

  By the way, an organic compound having a π-conjugated electron having a high charge transporting property is generally used as a constituent material of the organic light emitting device. Here, aromatic hydrocarbons such as benzene, heterocyclic compounds such as pyridine, fluorene derivatives, carbazole derivatives and the like are known as molecules having π-conjugated electrons.

However, when the molecule becomes large and π-conjugated electrons spread, T ₁ decreases. Therefore, Non-Patent Document 1 shows that organic compounds that can be used as a green phosphorescent material are very limited to CBP, TAPC, and PVK. Moreover, there are few organic compounds which can respond to a blue phosphorescence-emitting material.

  On the other hand, a compound having a triphenylene skeleton has been proposed as an organic compound having a π-conjugated electron having a high charge transporting property. Here, the organic light-emitting elements using organic compounds having triphenylene as the main skeleton as constituent materials are disclosed in Patent Documents 1 to 5 and the like.

  However, in the organic compounds disclosed in Patent Documents 2 to 4, the triphenylene moiety of the main skeleton and the π-conjugated electron system of the side chain are connected by a hetero atom such as an oxygen atom or a nitrogen atom. For this reason, the π-conjugation of the triphenylene main skeleton and the π-conjugation of the side chain are cleaved by the heteroatom, so that improvement in charge transportability cannot be expected.

Further, the organic compound disclosed in Patent Document 5 has a low T ₁ because the main skeleton is benzotriphenylene, and is difficult to apply to green light emission and blue light emission. On the other hand, the organic compound disclosed in Patent Document 1 is a compound in which a benzene ring having a π-shared electron is directly bonded to a triphenylene main skeleton, and is used as a hole blocking material corresponding to a green phosphorescent material. Yes.

JP 2005-259472 A JP-A-11-251063 Japanese Patent Laid-Open No. 11-8072 JP 2000-91080 A Japanese Patent Laid-Open No. 11-283748 J. et al. Am. Chem. Soc. , 123, 4304 (2001)

  An object of the present invention is to provide an organic light emitting material having good luminous efficiency, in particular, a triphenylene compound that can be used with a blue light emitting material, a blue / green light emitting material, or a red light emitting material.

  The triphenylene compound of the present invention is represented by the following general formula (1).

（式（１）において、Ａ₁乃至Ａ₆は、それぞれ水素原子又は下記一般式（２）乃至（４）の中から選択される置換基である。ただし、Ａ₁及びＡ₂のいずれか、Ａ₃及びＡ₄のいずれか、並びにＡ₅及びＡ₆のいずれかは、下記一般式（２）乃至（４）の中から選択される置換基である。

(In the formula (1), A _{1 to} A ₆ are each a hydrogen atom or a substituent selected from the following general formulas (2) to (4). However, any _one of A ₁ and A ₂ , Any of A ₃ and A ₄ and any of A ₅ and A ₆ is a substituent selected from the following general formulas (2) to (4).

（式（２）において、Ｘ₁は、下記一般式（５）又は（６）で示される部分構造である。

(In Formula (2), X < ₁ > is the partial structure shown by the following general formula (5) or (6).

In Formula (3), X ₂ is a partial structure represented by any of the following General Formulas (7) to (12).

In formulas (2) to (4), Y _{1 to} Y ₄ are partial structures represented by any of the following general formulas (13) to (20), respectively.

（式（１３）乃至（２０）において、Ｒ₁乃至Ｒ₁₂は、それぞれ置換あるいは無置換のアルキル基、置換あるいは無置換のシクロアルキル基、置換あるいは無置換のアルケニル基、置換あるいは無置換のシクロアルケニル基、置換あるいは無置換のアリール基又は水素原子を表す。ａ乃至ｄは、それぞれ１以上９以下の整数を表す。ａ乃至ｄが２以上の場合、繰り返し単位であるフルオレンユニット又はカルバゾールユニットは同じであっても異なってもよい。）

(In the formulas (13) to (20), R _{1 to} R ₁₂ are each a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted cyclohexane. An alkenyl group, a substituted or unsubstituted aryl group, or a hydrogen atom, each of a to d represents an integer of 1 to 9. When a to d is 2 or more, a fluorene unit or a carbazole unit as a repeating unit is It can be the same or different.)

In formulas (2) to (4), Z _{1 to} Z ₄ are each a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted cycloalkenyl. Represents a group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted amino group, a hydrogen atom or a halogen atom. ))

  ADVANTAGE OF THE INVENTION According to this invention, the triphenylene compound which can be used with organic luminescent material with favorable luminous efficiency, especially blue luminescent material, blue and green luminescent material, or red luminescent material can be provided.

  First, the triphenylene compound of the present invention will be described. The triphenylene compound of the present invention is represented by the following general formula (1).

In the formula (1), A _{1 to} A ₆ are each a hydrogen atom or a substituent selected from the following general formulas (2) to (4). However, any _one of A ₁ and A ₂ , any one of A ₃ and A ₄ , and any one of A ₅ and A ₆ is a substituent selected from the following general formulas (2) to (4): is there. Preferably, A _{1 to} A ₆ are the same substituent. In this case, the same substituent is a substituent selected from the following general formulas (2) to (4).

In Formula (2), X ₁ is a partial structure represented by the following General Formula (5) or (6).

In Formula (3), X ₂ is a partial structure represented by any of the following General Formulas (7) to (12).

In formulas (2) to (4), Y _{1 to} Y ₄ are partial structures each composed of one or more fluorene skeletons or carbazole skeletons. Details of this partial structure will be described later.

In formulas (2) to (4), Z _{1 to} Z ₄ are each a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted cycloalkenyl. Group, substituted or unsubstituted alkoxy group, substituted or unsubstituted aryl group, substituted or unsubstituted aryloxy group, substituted or unsubstituted fluorenyl group, substituted or unsubstituted carbazolyl group, substituted or unsubstituted amino group Represents an acetyl group, a halogen atom or a hydrogen atom.

Examples of the alkyl group represented by Z _{1 to} Z ₄ include a methyl group, a trifluoromethyl group, an ethyl group, a tert-butyl group, a 3-methyl-butyl group, a pentyl group, a 2-ethyl-hexyl group, and an octyl group. Can be mentioned.

Examples of the cycloalkyl group represented by Z _{1 to} Z ₄ include a cyclopentyl group, a cyclohexyl group, a cyclooctyl group, an adamantanyl group, and a methylcyclohexyl group.

Examples of the alkenyl group represented by Z _{1 to} Z ₄ include a vinyl group, a 1-propenyl group, a 2-propenyl group, an iso-propenyl group, and a 2-butenyl group.

Examples of the cycloalkenyl group represented by Z _{1 to} Z ₄ include a cyclopentenyl group, a cyclohexenyl group, a cyclohexedienyl group, and a cyclooctenyl group.

Examples of the alkoxy group represented by Z _{1 to} Z ₄ include a methoxy group, an ethoxy group, a propoxy group, a 2-ethyl-octyloxy group, and a benzyloxy group.

As the aryl group represented by Z _{1 to} Z ₄ , phenyl group, 4-methylphenyl group, 4-ethylphenyl group, tert-butylphenyl group, 4-octylphenyl group, 3,5-dimethylphenyl group, diphenylamino Examples include a phenyl group, a biphenyl group, a terphenyl group, and a pyridyl group.

Examples of the aryloxy group represented by Z _{1 to} Z ₄ include a phenoxy group and a 4-butylphenoxy group.

Examples of the amino group having a substituent represented by Z _{1 to} Z ₄ include a dimethylamino group, a diethylamino group, a dibenzylamino group, a diphenylamino group, a ditolylamino group, a dianisolylamino group, and di (tert-butylphenyl) amino. Groups and the like.

Examples of the halogen atom represented by Z _{1 to} Z ₄ include fluorine, chlorine, bromine or iodine.

  As the substituents that the alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, alkoxy group, aryl group, aryloxy group, fluorenyl group and carbazolyl group may further have, a methyl group, a trifluoromethyl group, Alkyl groups such as ethyl group, tert-butyl group, 3-methylbutyl group, hexyl group, 2-ethylhexyl group, octyl group, cyclopentyl group, cyclohexyl group, cyclooctyl group, adamantanyl group, cycloalkyl group such as methylcyclohexyl group, Alkenyl groups such as vinyl group, 1-propenyl group, 2-propenyl group, iso-propenyl group and 2-butenyl group, cycloalkenyl groups such as cyclopentenyl group, cyclohexenyl group, cyclohexedenyl group and cyclooctenyl group, phenyl 4-methyl Aryl group such as phenyl group, 4-ethylphenyl group, tert-butylphenyl group, 4-octylphenyl group, 3,5-dimethylphenyl group, diphenylaminophenyl group, biphenyl group, terphenyl group, dimethylamino group, diethylamino Group, a dibenzylamino group, a diphenylamino group, a ditolylamino group, a dianisolylamino group and other substituted amino groups, a halogen atom which is fluorine, chlorine, bromine or iodine, and a cyano group. However, the present invention is not limited to these.

Next, the partial structures represented by Y _{1 to} Y ₄ in the formulas (2) to (4) will be described in detail. The partial structure represented by Y _{1 to} Y ₄ is a partial structure composed of one or more fluorene skeletons or carbazole skeletons represented by the following general formulas (13) to (20).

In formulas (13) to (20), R _{1 to} R ₁₂ are each a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted cycloalkenyl. Represents a group, a substituted or unsubstituted aryl group or a hydrogen atom.

Examples of the alkyl group represented by R _{1 to} R ₁₂ include a methyl group, a trifluoromethyl group, an ethyl group, a tert-butyl group, a 3-methylbutyl group, a hexyl group, a 2-ethylhexyl group, and an octyl group.

Examples of the cycloalkyl group represented by R _{1 to} R ₁₂ include a cyclopentyl group, a cyclohexyl group, a cyclooctyl group, an adamantanyl group, a methylcyclohexyl group, and the like.

Examples of the alkenyl group represented by R _{1 to} R ₁₂ include a vinyl group, a 1-propenyl group, a 2-propenyl group, an iso-propenyl group, and a 2-butenyl group.

Examples of the cycloalkenyl group represented by R _{1 to} R ₁₂ include a cyclopentenyl group, a cyclohexenyl group, a cyclohexedienyl group, and a cyclooctenyl group.

As the aryl group represented by R _{1 to} R ₁₂ , phenyl group, 4-methylphenyl group, 4-ethylphenyl group, tert-butylphenyl group, 4-octylphenyl group, 3,5-dimethylphenyl group, triphenyl An amino group, a biphenyl group, a terphenyl group, a naphthyl group, etc. are mentioned.

  Examples of the substituent that the alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group and aryl group may further include a methyl group, a trifluoromethyl group, a tert-butyl group, a 2-methyl-butyl group, 2 -Alkyl group such as ethyl-hexyl group and octyl group, cyclopentyl group, cyclohexyl group, cyclooctyl group, adamantanyl group, cycloalkyl group such as methylcyclohexyl group, vinyl group, 1-propenyl group, 2-propenyl group, iso- Alkenyl groups such as propenyl group, 2-butenyl group, cyclopentenyl group, cyclohexenyl group, cyclohexedienyl group, cyclooctenyl group and other cycloalkenyl groups, phenyl group, 4-methylphenyl group, 4-ethylphenyl group, tert -Butylphenyl group, 4-octylpheny Group, aryl group such as 3,5-dimethylphenyl group, diphenylaminophenyl group, biphenyl group, terphenyl group, dimethylamino group, diethylamino group, dibenzylamino group, diphenylamino group, ditolylamino group, dianisolylamino group A substituted amino group such as fluorine, chlorine, bromine or iodine, and a cyano group. However, the present invention is not limited to these.

  In the formulas (13) to (20), a to d each represent an integer of 1 to 9. When a to d are 2 or more, the fluorene unit or carbazole unit which is a repeating unit may be the same or different. In addition, the emission wavelength of the compound itself can be adjusted by appropriately adjusting a to d and adjusting the number of fluorene units or carbazole units.

  In addition, since the film itself can be formed by vacuum deposition if the compound itself has sublimability, a to d are not limited by whether the element manufacturing process is a vacuum deposition process or a coating process. Absent.

The triphenylene compound of the present invention has the following excellent features.
1. In the triphenylene compound of the present invention, triphenylene as a main skeleton is a rare compound having both a developed π-conjugated electron system and a high T ₁ level (3 eV). Therefore, the triphenylene compound of the present invention can be used with a blue, green or red phosphorescent light emitting material.
2. In the triphenylene compound of the present invention, the lowest singlet excitation energy in the fluorescent state is larger than the lowest triplet excitation energy (T ₁ ) in the phosphorescent state. For this reason, the triphenylene compound of the present invention can be used with blue, green or red fluorescent materials.
3. In the triphenylene compound of the present invention, triphenylene which is the main skeleton emits fluorescence. Therefore, the triphenylene compound of the present invention can be used as a fluorescent material.
4). In the triphenylene compound of the present invention, the π-conjugated electron of the triphenylene skeleton and the π-conjugated electron system of the substituents A _{1 to} A ₆ are directly bonded. For this reason, the triphenylene compound of the present invention is chemically very stable, and the π-conjugated electron system is expanded, so that an improvement in charge mobility can be expected.
5. The substituents A _{1 to} A ₆ are bulky and cause steric hindrance between adjacent or adjacent substituents. For this reason, the π-conjugated electron system of the triphenylene skeleton and the π-conjugated electron system of the substituents A _{1 to} A ₆ are orthogonal or nearly orthogonal. Therefore, high T ₁ can be maintained while maintaining the continuity of both π-conjugated electron systems.
6). A fluorene skeleton, a carbazole skeleton, or the like that has been known as a skeleton having high charge transport performance can be introduced into the substituents A _{1 to} A ₆ .
7. The substituents A _{1 to} A ₆ are not necessarily the same, and two or more different substituents may be introduced. As a result, a single molecule can have a plurality of functions.
8). The molecular weight can be increased by introducing the substituents A _{1 to} A ₆ into the triphenylene skeleton. Further, by introducing the substituents A _{1 to} A ₆ , the planarity of the molecule itself is lost, so that the amorphous nature is enhanced. Therefore, a stable thin film can be formed when an organic light emitting device is produced.

  As described above, when the triphenylene compound of the present invention is used as a constituent material of an organic light emitting device, highly efficient and stable light emission derived from the features of the triphenylene compound can be obtained.

In particular, when a phosphorescent material is used as a guest and a light emitting layer using the triphenylene compound of the present invention as a host is formed, an organic light emitting device having high electroluminescence efficiency utilizing the high T ₁ level of the triphenylene compound can be obtained. Is possible.

Further, when the triphenylene compound of the present invention is used as a constituent material of a layer adjacent to the layer containing the phosphorescent light emitting material, organic light emission having high electroluminescence efficiency utilizing the high T ₁ level of the triphenylene compound of the present invention. It is possible to obtain an element.

  Representative examples of the organic compound represented by the general formula [1] are listed below, but the present invention is not limited thereto.

  Next, the organic light emitting device of the present invention will be described. The organic electroluminescent element of the present invention comprises an anode, a cathode, and a layer made of an organic compound sandwiched between the anode and the cathode.

  Hereinafter, the organic light-emitting device of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a cross-sectional view showing an example of an embodiment of the organic light-emitting device of the present invention, (a) is a cross-sectional view showing the first embodiment, and (b) is a cross-section showing the second embodiment. It is a figure, (c) is sectional drawing which shows 3rd embodiment.

  In the organic light emitting device 1 of FIG. 1A, a laminate in which a metal electrode 11, a light emitting layer 12, a hole injection layer 13, and a transparent electrode 14 are laminated in this order from the top is provided on a transparent substrate 15. . In the organic light emitting device 1 of FIG. 1A, when an electric field is applied so that the metal electrode 11 serves as a cathode and the transparent electrode 14 serves as an anode, electrons are injected from the metal electrode 11 into the light emitting layer 12. Holes are injected. The injected holes and electrons recombine in the light emitting layer 12 to generate excitons of the light emitting material, and the organic light emitting device 1 emits light when the excitons return to the ground state.

  In the organic electroluminescent element 2 of FIG. 1B, an interlayer 16 is provided between the light emitting layer 12 and the hole injection layer 13 in the organic electroluminescent element 1 of FIG. Providing the interlayer 16 has the effect of blocking electrons more effectively and blocking ions moving from the transparent electrode 14 and the hole injection layer 13, thereby improving the light emission efficiency and durability of the device. .

  In the organic electroluminescent element 3 of FIG. 1C, a laminate in which the metal electrode 11, the multifunctional light emitting layer 17, and the transparent electrode 14 are laminated in this order from the top is provided on the transparent substrate 15. The organic light emitting device of the present invention may have a configuration in which only one organic compound layer is formed as shown in FIG. In this case, the organic compound layer needs to be a layer having a plurality of functions such as a light emitting function (multifunctional light emitting layer). For this reason, it is preferable to use the multifunctional triphenylene compound of the present invention.

  Here, the organic light-emitting device of the present invention is characterized in that at least one type of triphenylene compound of the present invention is contained in a layer made of an organic compound. Here, the layer made of an organic compound is specifically any one of the light emitting layer 12, the hole injection layer 13, the interlayer 16, and the multifunctional light emitting layer 17 shown in FIGS. It is.

  The triphenylene compound of the present invention is preferably included in the light emitting layer 12 or the multifunctional light emitting layer 17. Here, although the light emitting layer 12 and the multifunction light emitting layer 17 may be comprised only with the triphenylene compound of this invention, they may be comprised from the host and the guest. When the light emitting layer 12 or the multifunctional light emitting layer 17 is composed of a host and a guest, the triphenylene compound of the present invention is a host for a fluorescent or phosphorescent light emitting material (guest). The light emitting layer 12 and the multifunctional light emitting layer 17 may be configured by combining a charge transport material that is a third material in addition to the host and the guest.

  Specific examples of fluorescent light-emitting materials that serve as guests of the light-emitting layer 12 or the multifunctional light-emitting layer 17 include benzoxazole and its derivatives, benzimidazole and its derivatives, benzothiazole and its derivatives, styrylbenzene and its derivatives, polyphenyl and Derivatives thereof, diphenylbutadiene and derivatives thereof, tetraphenylbutadiene and derivatives thereof, naphthalimide and derivatives thereof, coumarin and derivatives thereof, condensed aromatic compounds, perinone and derivatives thereof, oxadiazole and derivatives thereof, oxazine and derivatives thereof, aldazine And its derivatives, pyralidine and its derivatives, cyclopentadiene and its derivatives, bisstyrylanthracene and its derivatives, quinacridone and its derivatives, pyrrolopyridine and its derivatives, thiadiazolopyri And derivatives thereof, cyclopentadiene and derivatives thereof, styrylamine and derivatives thereof, diketopyrrolopyrrole and derivatives thereof, aromatic dimethylidin compounds, metal complexes having 8-quinolinol and derivatives thereof as ligands, pyromethene and Examples thereof include metal complexes having any of the derivatives as ligands, rare earth complexes, various metal complexes represented by transition metal complexes, polymer compounds such as polythiophene, polyphenylene, and polyphenylene vinylene, organic silanes, and derivatives thereof.

As the phosphorescent light emitting material to be a guest of the light emitting layer 12 or the multifunctional light emitting layer 17, a transition metal complex is preferable. The central metal of the transition metal complex is not particularly limited, but is preferably iridium, platinum, rhenium, or ruthenium, more preferably iridium or platinum, and particularly preferably iridium. Specifically, ortho-metalated complexes described in the following documents can be used.
1. Akio Yamamoto, “Organic Metals Fundamentals and Applications”, p. 150 and p. 232, Shukubosha (1982)
2. H. Yersin, “Photochemistry and Photophysics and Photophysics of Coordination Compound”, pages 71-77 and 135-146, Springer V )
3. (Germany) Japan Society for the Promotion of Science "Organic Materials for Information Science, 142nd Committee", Group C (Organic Electronics), 9th Workshop Material, 25-32 (2005)

  In addition to the above, those disclosed in patent documents such as US Pat. No. 6,303,231, US Pat. No. 6,097,147, WO00 / 57676, WO00 / 70655, WO01 / 08230, WO01 / 39234 pamphlet, WO01 / 41512 pamphlet, WO02 / 02714 pamphlet, WO02 / 15645 pamphlet, Japanese Patent Application No. 2001-247859, Japanese Patent Application No. 2000-33561, Japanese Patent Application No. 2001-189539, and Japanese Patent Application No. 2001-248165. No., Japanese Patent Application No. 2001-33684, Japanese Patent Application No. 2001-239281, Japanese Patent Application No. 2001-219909, European Patent No. 1211,257, Japanese Patent Application Laid-Open No. 2002-226495, Japanese Patent Application Laid-Open No. 2002-234. 94, JP 2001-247859 A, JP 2001-298470 A, JP 2002-173694 A, JP 2002-203678 A, JP 2002-203679 A, and the like. Luminescent materials can be suitably used.

  Also disclosed in non-patent literature, for example, Nature, 395, 151 (1998), Applied Physics Letters, 75, 4 (1999), Polymer Preprints, 41, 770 (2000), Journal of American Chemical Society, 123, 4304 (2001), Applied Physics Letters (Applied Physics Letters), 79, 2082 (1999), etc. can also be used suitably.

  Examples of the charge transport material that is the third material include triarylamine derivatives, phenylenediamine derivatives, triazole derivatives, oxadiazole derivatives, imidazole derivatives, pyrazoline derivatives, pyrarozone derivatives, oxazole derivatives, fluorenone derivatives, polyvinylcarbazole, polysilylene, polythiophene. Hole transport compounds such as, oxadiazole derivatives, oxazole derivatives, thiazol derivatives, thiadiazole derivatives, pyrazine derivatives, triazole derivatives, triazine derivatives, perylene derivatives, quinoline derivatives, quinoxaline derivatives, fluorenone derivatives, anthrone derivatives, phenanthroline derivatives, And electron transporting compounds such as organometallic complexes.

  Next, other constituent members constituting the organic light emitting device of the present invention will be described.

  Although the material used as the transparent substrate 15 is not specifically limited, For example, polymer materials, such as inorganic materials, such as glass, polyester, such as a polyethylene terephthalate, are mentioned. It is also possible to control the color light by using a color filter film, a dielectric reflection film or the like on the substrate.

  The transparent electrode 14 is provided on the transparent substrate 15 and has a thickness of 50 nm to 500 nm. Although the material used as the transparent electrode 14 is not specifically limited, Preferably, it is a material whose work function is 4 eV or more. Specifically, it is a conductive metal oxide, and among them, ITO is preferable from the viewpoint of productivity, high conductivity, transparency, and the like.

  The metal electrode 11 is provided together with the transparent electrode 14 to sandwich the organic compound layer. Although the material used as the metal electrode 11 is not specifically limited, Preferably, it is a material whose work function is 4 eV or less. Here, a laminated structure of aluminum / cesium carbonate or the like can also be employed.

  The material for the interlayer 16 is not particularly limited as long as it is a wide gap, has a carrier transport ability, and is excellent in stability such as electrical, chemical, or thermal properties. For example, polyvinylcarbazole (PVK) or the like. Is mentioned.

  The organic light-emitting device of the present invention is manufactured by a device manufacturing process that employs either a vacuum deposition process or a coating process, depending on the constituent material. Here, when manufacturing an organic light emitting device by a coating process, a spin coating method, an inkjet method, a printing method (offset, gravure, convex, concave, screen printing, etc.), a spray method, and an electrophotographic method are applied as specific processes. The liquid developing method can be employed. However, the present invention is not limited to this.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated in detail, this invention is not limited to these.

  Example 1 Exemplified Compound No. 1 Synthesis of 106

The following reagents and solvents were charged into a 100 cc three-necked flask.
Compound A001: 351 mg (0.5 mmol)
Compound A002: 2160 mg (5 mmol)
Na ₂ CO ₃ : 4.8 g)
toluene: 20ml
EtOH: 10ml
water: 30ml

Next, the reaction solution was deaerated by flowing a nitrogen stream for 20 minutes. Next, 173 mg (0.15 mmol) of Pd (PPh ₃ ) ₄ was put into the reaction solution, and then a condenser tube was attached to the three-necked flask. Next, the oil bath temperature was set to 90 ° C., and the reaction solution was stirred for 7 hours while being heated in the oil bath. Next, after cooling the reaction solution, chloroform and water were added, and the organic solvent layer was extracted and dried over Mg ₂ SO ₄ . Next, this organic solvent layer was filtered and the solvent was distilled off under reduced pressure to obtain a brown liquid. This liquid was first purified by silica gel column chromatography using a heptane / toluene mixed solvent (volume ratio: 5/5) as a developing solvent. However, since the substance obtained by this purification was insufficient in purity, the second purification was further performed by silica gel column chromatography using a heptane / chloroform mixed solvent (volume ratio: 6/4) as a developing solvent. The clear solution obtained by the second purification was dried under reduced pressure, whereby Exemplified Compound No. As a white substance, 106 mg (synthesis yield = 14.5%) was obtained.

  The obtained Exemplified Compound No. 106 was identified by NMR (500 MHz) using a Bruker AVANCE-500. The NMR chart obtained at that time is shown in FIG. Also, Elemental Co. Elemental analysis was performed using an elemental analyzer Vario EL CHNOS manufactured by the manufacturer. As a result, as shown below, it was found that the measured value almost coincided with the calculated value.

Measurement C: 91.1, H: 8.9
Calculated value C: 91.2, H: 8.8

  Example 2 Exemplified Compound No. Synthesis of 107

The following reagents and solvents were charged into a 100 cc three-necked flask.
Compound A001: 351 mg (0.5 mmol)
Compound A003: 2160 mg (5 mmol)
Na ₂ CO ₃ : 4.8 g
toluene: 20ml
EtOH: 10ml
water: 30ml

Next, the reaction solution was deaerated by flowing a nitrogen stream for 20 minutes. Next, 173 mg (0.15 mmol) of Pd (PPh ₃ ) ₄ was put into the reaction solution, and then a condenser tube was attached to the three-necked flask. Next, the oil bath temperature was set to 90 ° C., and the reaction solution was stirred for 5 hours while being heated in the oil bath. Next, after cooling the reaction solution, chloroform and water were added, and the organic solvent layer was extracted and dried over Mg ₂ SO ₄ . Next, the organic solvent layer was filtered, and the solvent was distilled off under reduced pressure to obtain a brown liquid. This liquid was first purified by silica gel column chromatography using a heptane / toluene mixed solvent (volume ratio: 5/5) as a developing solvent. However, since the substance obtained by this purification was insufficient in purity, it was further purified a second time by silica gel column chromatography using a mixed solvent of heptane / chloroform (volume ratio: 6/4) as a developing solvent. The clear solution obtained by the second purification was dried under reduced pressure, whereby Exemplified Compound No. Thus, 110 mg (synthesis yield = 11%) of 107 was obtained as a white substance.

  The obtained Exemplified Compound No. 107 was identified by NMR (500 MHz) using a Bruker AVANCE-500. The NMR chart obtained at that time is shown in FIG. Also, Elemental Co. Elemental analysis was performed using an elemental analyzer Vario EL CHNOS manufactured by the manufacturer. As a result, as shown below, it was found that the measured value almost coincided with the calculated value.

Measurement value C: 91.0, H: 8.9
Calculated value C: 91.2, H: 8.8

  Example 3 Exemplified Compound No. 115 synthesis

The following reagents and solvents were charged into a 100 cc three-necked flask.
Compound A001: 176 mg (0.25 mmol)
Compound A004: 1972 mg (2.5 mmol)
Na ₂ CO ₃ : 4.8 g
toluene: 20ml
EtOH: 10ml
water: 30ml

Next, the reaction solution was deaerated by flowing a nitrogen stream for 15 minutes. Next, 87 mg (0.08 mmol) of Pd (PPh ₃ ) ₄ was added to the reaction solution, and then a condenser tube was attached to the three-necked flask. Next, the oil bath temperature was set to 90 ° C., and the reaction solution was stirred for 5 hours while being heated in the oil bath. Next, after cooling the reaction solution, chloroform and a saturated aqueous solution of NaCl were added, and the organic solvent layer was extracted and dried over Mg ₂ SO ₄ . Next, the organic solvent layer was filtered, and the solvent was distilled off under reduced pressure to obtain a brown liquid. This liquid was first purified by silica gel column chromatography using a mixed solvent of heptane / chloroform (volume ratio: 5/5) as a developing solvent. However, since the substance obtained by the first purification is insufficient in purity, the second purification is further performed by silica gel column chromatography using a mixed solvent of heptane / chloroform (volume ratio: 6/4) as a developing solvent. It was. Next, the transparent solution obtained by the second purification was dried under reduced pressure, whereby Exemplified Compound No. 124 mg (synthesis yield = 12%) of 115 was obtained as a white substance.

  The obtained Exemplified Compound No. 115 was identified by NMR (500 MHz) using a Bruker AVANCE-500. The NMR chart obtained at that time is shown in FIG. Also, Elemental Co. Elemental analysis was performed using an elemental analyzer Vario EL CHNOS manufactured by the manufacturer. As a result, as shown below, it was found that the measured value almost coincided with the calculated value.

Measurement C: 92.6, H: 7.3
Calculated value C: 92.8, H: 7.2

  Example 4 Exemplified Compound No. 112 synthesis

(1) Reagents and solvents shown below were charged into a 100 cc three-neck flask.
Compound A005: 798 mg (2 mmol)
Compound A006: 618 mg (2.2 mmol)
Pd ₂ (dba) ₃ : 92 mg (0.1 mmol)
1,4-dioxane: 20 ml

Next, nitrogen gas was passed through the reaction solution for 20 minutes. Next, t-BuONa (288 mg, 3.0 mmol) and (t-Bu) ₃ P (162 mg, 0.8 mmol) were added, and a condenser tube was attached. Next, the temperature of the oil bath was set to 65 ° C., and the reaction solution was stirred for 8 hours while being heated in the oil bath. Next, after cooling the reaction solution, a yellow precipitate was obtained by filtration. Next, this precipitate was washed successively with acetone and methanol to obtain 600 mg of Compound A007 as yellow crystals (yield 54%).

(2) The following reagents and solvents were charged in the reaction vessel.
Compound A007: 553 mg (1 mmol)
Compound A008: 640 mg (5 mmol)
Triethylamine: 0.3ml
Ni (dppp) Cl ₂ catalyst: 108 mg (0.2 mmol)
Toluene: 20ml

  Next, the reaction solution was heated to 120 ° C. and stirred for 7.5 hours. Next, the reaction solution was cooled to room temperature and then purified by silica gel column chromatography (developing solvent: chloroform / heptane = 1/1) to obtain 300 mg of Compound A009 (yield 50%).

(3) Reagents and solvents shown below were charged into a 100 cc three-necked flask.
Compound A001: 35 mg (0.05 mmol)
Compound A009: 300 mg (0.5 mmol)
Cs ₂ CO ₃ : 1.6 g (5 mmol)
(toluene: 20ml)

Next, the reaction solution was deaerated by flowing a nitrogen stream for 15 minutes. Next, 69 mg (0.06 mmol) of Pd (PPh ₃ ) ₄ was put into the reaction solution, and then a condenser tube was attached to the three-necked flask. Next, the oil bath temperature was set to 120 ° C., and the reaction solution was stirred for 5 hours while being heated in the oil bath. Next, after cooling the reaction solution, chloroform and a saturated aqueous solution of NaCl were added, and the organic solvent layer was extracted and dried over Mg ₂ SO ₄ . Next, the organic solvent layer was filtered, and the solvent was distilled off under reduced pressure to obtain a brown liquid. This liquid was purified by silica gel column chromatography using a mixed solvent of heptane / chloroform (volume ratio: 6/4) as a developing solvent. The pale yellow solution obtained by this purification was dried under reduced pressure to give Exemplified Compound Nos. As a white substance, 112 mg of 65 mg (synthesis yield = 21%) was obtained.

The obtained Exemplified Compound No. 112, Elemental Co. Elemental analysis was performed using an elemental analyzer Vario EL CHNOS manufactured by the manufacturer. As a result, as shown below, it was confirmed that the measured value almost coincided with the calculated value.
Measured value C: 89.7, H: 7.6, N: 2.8
Calculated value C: 89.5, H: 7.7, N: 2.8

  From the above, Exemplified Compound No. 112 could be identified.

(Measurement of fluorescence and phosphorescence spectrum)
Exemplified Compound No. 106, Exemplified Compound No. 107 and Exemplified Compound No. For 115, a fluorescence spectrum and a phosphorescence spectrum in a 2-methyltetrahydrofuran solution were measured. When measuring the fluorescence / phosphorescence spectrum, a Hitachi spectrophotometer F4500 was used. Here, the fluorescence spectrum was measured at a temperature condition of 298K, and the phosphorescence spectrum was measured at a temperature condition of 77K. The fluorescence / phosphorescence spectrum obtained by the measurement is shown in FIG. Here, FIG. The fluorescence / phosphorescence spectrum of No. 106 is shown in FIG. The fluorescence / phosphorescence spectrum of No. 107 is shown in FIG. 115 shows fluorescence and phosphorescence spectra of 115, respectively. In addition, the shortest emission peak wavelength in each compound is summarized in the following table.

  From this table, each compound showed blue fluorescence emission of 397 nm to 419 nm at room temperature. Further, the emission efficiency of this fluorescence was good.

As a result of fluorescence / phosphorescence spectrum measurement, it was found that no phosphorescence emission peak was observed at room temperature. On the other hand, at a low temperature of 77K, it was found that fluorescence was observed on the short wavelength side and phosphorescence was observed on the long wavelength side. Here, since phosphorescence has a longer emission lifetime than fluorescence, only phosphorescence can be observed by separating fluorescence emission and phosphorescence emission by a chopper after turning off excitation light. From Table 1, it was found from Table 1 that the shortest wavelength peak of phosphorescence emission observed by separating fluorescence emission and phosphorescence emission was 484 nm to 555 nm. These peak wavelengths represent T ₁ of each compound.

  The following can be understood from the characteristics of these emission spectra.

  (1) The compound of the present Example can be used as a blue fluorescent light emitting material (dopant) of an organic light emitting device.

  (2) The compound of this example can be used as a host of a light emitting layer of a blue, green or red phosphorescent light emitting device.

In particular, in the case of (2), in order to efficiently obtain a light emission from the phosphorescent guest, it is essential T ₁ of the host is higher than the T ₁ of the guest. In other words, when the peak wavelength of phosphorescence emission of a phosphorescent guest is λ _P and the peak wavelength of phosphorescence emission on the short wavelength side of the host is λ _H , “λ _P > λ _H ” may be satisfied. is important. If this condition is satisfied, the phosphorescence energy of the phosphorescent guest is not quenched by the host. From Table 1, Exemplified Compound No. 106, Exemplified Compound No. 107 and Exemplified Compound No. Since the peak of phosphorescence emission of 115 is 484 nm to 555 nm, these compounds can be used as a host of blue, green, or red phosphorescent light emitting elements.

Even when the compound of this example is used in a layer adjacent to the light emitting layer, in order to obtain a highly efficient organic light emitting element, T ₁ of the constituent material of the layer adjacent to the light emitting layer is the guest of the light emitting layer. it is essential higher than T _1. Here, from Table 1, Exemplified Compound No. 106, Exemplified Compound No. 107 and Exemplified Compound No. The peak of 115 phosphorescent emission is 484 to 555 nm. For this reason, these compounds can be used for the organic layer adjacent to the light emitting element of a blue, green, or red phosphorescent light emitting element.

(Example 5)
An organic light emitting device having a device configuration as shown in FIG. In addition, since the triphenylene compound of the present invention has a low molecular weight, a stable film can be formed by a vapor deposition method, and thus it is possible to produce a device using the vapor deposition method. However, in order to clarify the excellent characteristics and superiority of the triphenylene compound of the present invention, a device was produced by the following method.

First, indium tin oxide (ITO) was patterned on a glass substrate (transparent substrate 15) so as to have an electrode area of 3.14 mm ² to form a transparent electrode 14. At this time, the film thickness of the transparent electrode 14 was 100 nm.

  Next, all organic compound layers were formed on the substrate with ITO electrodes by a spin coating method. A specific method is shown below.

  First, after making nitrogen atmosphere, PEDOT / PSS AI 4083 (manufactured by Baytron) was dropped on a substrate with an ITO electrode, and a thin film was formed by spin coating at 4000 rpm for 2 minutes. Subsequently, the hole injection transport layer 13 was formed by drying at 200 ° C. for 10 minutes. At this time, the thickness of the hole injecting and transporting layer 13 was 400 mm.

  Next, a chlorobenzene solution in which polyvinylcarbazole (PVK, manufactured by Aldrich) was dissolved was dropped onto PEDOT / PSS in a nitrogen atmosphere, and a thin film was formed by spin coating at 1000 rpm for 1 minute. Subsequently, the interlayer 16 was formed by drying at 140 ° C. for 30 minutes. At this time, the film thickness of the interlayer 16 was 200 mm.

  Next, Exemplified Compound No. which is a host. 106 and an Ir complex (emission peak: 525 nm) shown below as a guest were dissolved in p-xylene to prepare a 1 wt% p-xylene solution. At this time, the amount of the guest was set to 2% by weight with respect to the host.

  Subsequently, this p-xylene solution was dropped on the interlayer 16 in a nitrogen atmosphere, and a thin film was formed by spin coating at a rotation speed of 1000 rpm for 1 minute. Subsequently, the light emitting layer 12 was formed by drying at 140 ° C. for 10 minutes. At this time, the thickness of the light emitting layer 12 was 600 mm.

Next, a layer to be the metal electrode 11 was formed by a vacuum evaporation method under a reduced pressure of 10 ⁻⁴ Pa. Specifically, first, Cs ₂ (CO ₃ ) was deposited to form a first metal electrode. At this time, the thickness of the first metal electrode was 24 mm. Next, Al was vapor-deposited to form a second metal electrode. At this time, the thickness of the second metal electrode was set to 800 mm.

  Next, a protective glass plate was placed under a nitrogen atmosphere and sealed with an acrylic resin adhesive. An organic light emitting device was obtained as described above.

  The characteristics of the obtained device were evaluated. Specifically, the drive voltage, drive current, brightness, and organic EL emission spectrum were measured using an organic EL emission characteristic evaluation apparatus (manufactured by Cradle Co., Ltd.). The apparatus is composed of a dark box, a luminance meter, a multi-channel spectrometer, an element driving power source and an analyzing apparatus, and controls the driving current and driving voltage to the element by a program to measure the luminance and emission spectrum. Thereby, current-luminance characteristics, voltage-luminance characteristics, voltage-current characteristics, voltage-current efficiency, chromaticity, and the like of the element can be obtained.

  FIG. 6 is a diagram relating to the evaluation of the organic light emitting device in this example (Example 5), where (a) shows the relationship between drive voltage and luminance, and (b) shows drive voltage and current efficiency. It shows the relationship.

6 from (a), in the organic light emitting device of the present embodiment, the luminance when the driving voltage is 7V is 1000 cd / m ^2, the luminance when the drive voltage is 10V was 5000 cd / m ^2.

  From FIG. 6B, in the organic light emitting device of this example, the maximum value of the current efficiency was 17 cd / A when the driving voltage was 6V.

  In the organic light emitting device of this example, the peak of electroluminescence (EL) spectrum was 530 nm, and the CIE chromaticity coordinates were (x, y) = (0.32, 0.64).

  Further, the organic light-emitting device of this example showed stable light emission even when energized for 20 hours.

(Example 6)
In Example 5, the host of the light emitting layer 12 was designated as Exemplified Compound No. In place of 106, Exemplified Compound No. A device was fabricated in the same manner as in Example 5 except that 107 was used. The obtained device was evaluated in the same manner as in Example 5.

  FIG. 7 is a diagram relating to the evaluation of the organic light emitting device in this example (Example 6), where (a) shows the relationship between drive voltage and luminance, and (b) shows the drive voltage and current efficiency. It shows the relationship.

7 (a), in the organic light emitting device of the present embodiment, the luminance when the driving voltage is 8V is 1200 cd / m ^2, the luminance when the drive voltage is 10V was 5100cd / m ^2.

  From FIG. 7B, in the organic light emitting device of this example, the maximum value of the current efficiency was 6.5 cd / A when the drive voltage was 8V.

  In the organic light emitting device of this example, the peak of electroluminescence (EL) spectrum was 520 nm, and the CIE chromaticity coordinates were (x, y) = (0.32, 0.60).

Further, the organic light-emitting device of this example showed stable light emission even when energized for 20 hours.
(Example 7)
In Example 5, the host of the light emitting layer 12 was designated as Exemplified Compound No. In place of 106, Exemplified Compound No. 115 was replaced with the Ir complex used in Example 5 as the guest of the light emitting layer, and the following Ir complexes (emission peak: 620 nm) were used. In addition, the guest was 1% by weight with respect to the host.

  Except for these, an element was fabricated by the same method as in Example 5. The obtained device was evaluated in the same manner as in Example 5.

In the organic light emitting device of this example, the luminance was 1000 cd / m ² when the driving voltage was 6.5 V, and the luminance was 2000 cd / m ² when the driving voltage was 7 V. When the drive voltage was 6.5 V, the maximum current efficiency was 7 cd / A. The CIE chromaticity coordinates were (x, y) = (0.67, 0.32).

  Further, the organic light-emitting device of this example showed stable light emission even when energized for 20 hours.

  From the above, it has been found that the triphenylene compound of the present invention is a host for a light emitting layer that can correspond to a blue, green, or red phosphorescent light emitting material.

It is sectional drawing showing the example of embodiment in the organic light emitting element of this invention, (a) is sectional drawing which shows 1st embodiment, (b) is sectional drawing which shows 2nd embodiment, (C) is sectional drawing which shows 3rd embodiment. Exemplified Compound No. It is a figure which shows the NMR chart of 106. Exemplified Compound No. It is a figure which shows the NMR chart of 107. Exemplified Compound No. It is a figure which shows 115 NMR chart. (A) shows Exemplified Compound No. 106 shows the fluorescence / phosphorescence spectrum of Example 106. 107 shows the fluorescence / phosphorescence spectrum of No. 107. It is a figure which shows the fluorescence and phosphorescence spectrum of 115, respectively. It is a figure regarding evaluation of the organic light emitting element in Example 5, (a) is a figure which shows the relationship between a drive voltage and a brightness | luminance, (b) is a figure which shows the relationship between a drive voltage and current efficiency. It is a figure regarding evaluation of the organic light emitting element in Example 6, (a) is a figure which shows the relationship between a drive voltage and a brightness | luminance, (b) is a figure which shows the relationship between a drive voltage and current efficiency.

Explanation of symbols

1, 2, 3 Organic light emitting device 11 Metal electrode 12 Light emitting layer 13 Hole transport layer 14 Transparent electrode 15 Transparent substrate 16 Interlayer 17 Multifunctional light emitting layer

Claims (4)

A triphenylene compound represented by the following general formula (1):

(In the formula (1), A _{1 to} A ₆ are each a hydrogen atom or a substituent selected from the following general formulas (2) to (4). However, any _one of A ₁ and A ₂ , Any of A ₃ and A ₄ and any of A ₅ and A ₆ is a substituent selected from the following general formulas (2) to (4).

(In Formula (2), X < ₁ > is the partial structure shown by the following general formula (5) or (6).

In Formula (3), X ₂ is a partial structure represented by any of the following General Formulas (7) to (12).

In formulas (2) to (4), Y _{1 to} Y ₄ are partial structures represented by any of the following general formulas (13) to (20), respectively.

(In the formulas (13) to (20), R _{1 to} R ₁₂ are each a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted cyclohexane. An alkenyl group, a substituted or unsubstituted aryl group, or a hydrogen atom, each of a to d represents an integer of 1 to 9. When a to d is 2 or more, a fluorene unit or a carbazole unit as a repeating unit is It can be the same or different.)
In formulas (2) to (4), Z _{1 to} Z ₄ are each a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted cycloalkenyl. A group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted amino group, a hydrogen atom or a halogen atom; )) The triphenylene compound according to claim 1, wherein A _{1 to} A ₆ are the same substituent. An anode and a cathode;
A layer made of an organic compound sandwiched between the anode and the cathode,
An organic light-emitting device, wherein the layer made of the organic compound contains at least one triphenylene compound according to claim 1 or 2.   The organic light-emitting device according to claim 3, wherein the triphenylene compound is contained in a light-emitting layer.

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