TWI487770B - Organometallic complex compounds for organic light emitting display device and organic light emitting display device including the same - Google Patents

Description

Organometallic compound compound for organic light-emitting display element and organic light-emitting display element comprising same Background of the invention

The present invention relates to metal-doped compounds for organic light-emitting display elements and organic light-emitting display elements comprising the same for use in luminescent dopants. More specifically, the present invention relates to a metal-terminated compound for an organic light-emitting display element as a material for forming an emissive layer, and an organic light-emitting display element comprising the same for an emissive dopant.

The organic light emitting display element is a self-luminous display element that can be driven at a low voltage and has a wide viewing angle, good contrast, and fast response speed. Because it does not require a backlight, it can also be lightweight and thin.

In 1987, Eastman Kodak, Inc. first developed an organic light-emitting display element comprising a low molecular aromatic diamine and an aluminum complex as a material for forming an emissive layer [Appl. Phys. Lett. 51, 913, 1987]. CWTang et al. first disclosed an implementable element as an organic light-emitting display element in 1987 (Applied Physics Letters, 51, 12, 913-915, 1987). According to references, the organic layer has a film (hole transport layer (the HTL)) of a diamine derivative and reference (8-hydroxy - quinolinate) aluminum (Alq ₃₎ film of the laminated structure.

Generally, the light-emitting display element comprises an anode of a transparent electrode, an organic thin layer having a light-emitting region, and a metal electrode (cathode) formed on the glass substrate in the following order.

The organic thin layer may include an emission layer, a hole injection layer (HIL), and a hole transmission Transmission layer (HTL), electron transport layer (ETL) and electron injection layer (EIL). It may additionally comprise an electron suppression layer or a hole suppression layer due to the emission characteristics of the emissive layer.

An electric field is applied to the light-emitting display element, and holes and electrons are injected from the anode and the cathode, respectively. The injected holes and electrons recombine through the hole transport layer (HTL) and electron transport layer (ETL) on the emissive layer to provide luminescent excitons. The provided illuminating excitons emit light by transitioning to the ground state. Here, a luminescent colorant (dopant) is doped into the emission layer (body) to increase luminous efficiency and stability.

In the light-emitting display element, the luminescent material can be classified into a fluorescent material containing singlet excitons and a phosphorescent material containing triplet excitons according to a luminescent mechanism.

Recently, in addition to fluorescing materials, phosphorescent materials are known to be useful as luminescent materials (DFO'Brien et al., Applied Physics Letters, 74 3, 442-444, 1999; MA Baldo et al., Applied Physics Letters, 75 1 , 4-6, 1999).

The phosphorescent material emits light by transitioning electrons from a ground state to an excited state, causing a singlet exciton to be non-radiatively transitioned to a triplet exciton via intersystem switching, and a triplet exciton to a ground state to emit light.

When a triplet exciton transitions, it cannot directly transition to the ground state. Thus, the electron spins overturn and then transitions to the ground state so that it provides the feature that the lifetime (emission duration) is extended beyond the lifetime of the fluorescent emission.

In other words, the duration of the fluorescent emission is extremely short, in the order of a few nanoseconds, but the duration of the phosphorescence emission is relatively long, such as a few microseconds.

In addition, the quantum is evaluated mechanically, and when the hole injected from the anode and the electron injected from the cathode are recombined to provide an illuminating exciton, the singlet and triplet states are produced at a ratio of 1:3, wherein in the luminescent display element, The triplet luminescent excitons are produced by three times the amount of singlet luminescent excitons.

Therefore, in the case of a fluorescent material, the percentage of the singlet excited state is 25% (the triplet state is 75%), and thus it has limitations in luminous efficiency. On the other hand, in the case of a phosphorescent material, it can utilize 75% of the triplet excited state and 25% of the singlet excited state, so theoretically, the internal quantum efficiency can reach up to 100%. When a phosphorescent material is used, it has an advantage that the luminous efficiency is increased by about 4 times that of the fluorescent material.

The phosphorescent material has a molecular structure suitable for inter-system conversion. The molecular structure contains a heavy metal such as Ir, Pt, Rh or Pd in the organic molecule, which causes spin-orbit coupling, and thus the triplet state and the singlet state are mixed. Thereby, the transition is allowed to be suppressed and the emission of phosphorescence at room temperature can be effectively performed.

铱Organic metal complexes have received attention due to excellent phosphorescence luminescence efficiency, and phosphorescent materials containing the metal complex have been reported [Sergey Lamansky et al. Inorg. Chem., 40, 1704-1711, 2001 & J. Am. Chem. Soc, 123, 4304-4312, 2001].

The organometallic complex used to emit phosphorescence is a low molecular material that can be coated using a general dry process such as vacuum deposition. In the case of polymeric materials, it can be applied to the component using a wet process such as spin coating, ink jet printing or casting.

The wet method using a polymer makes component fabrication easier and cost-effective and scalable compared to a dry process such as vacuum deposition. Aspects have advantages. However, polymer materials have problems with lower lifetime, luminous efficiency, color purity, and the like, compared to low molecular materials.

Therefore, in order to solve such problems, it is required to develop a low molecular material which can be applied to a wet method due to high solubility.

Summary of the invention

According to an embodiment of the present invention, there is provided a metal-doped compound for an organic light-emitting display element which has improved solubility due to a bulky substituent and thus uses such as spin coating, ink jet printing or casting during the manufacture of the component Wet method to coat. According to another embodiment, an organic light emitting display element comprising the metal-miscible compound is provided.

The metal-substituted compound for an organic light-emitting display element contains a symmetrical anthracene derivative ligand represented by the following formula 1:

Wherein n is an integer in the range of 1 to 3, and a and b are independently 0 or 1; the ring of Formula 1 above may be a ring containing a double bond or a single bond; M is an octahedral complex. a metal; L is a bidentate ligand bonded to a monovalent anion of M via a covalent covalent bond with a sp ² carbon and a hetero atom, or an unpaired electron pair of a hetero atom and a hetero atom via a coordinating covalent bond a monodentate ligand of a monovalent anion of M; Y ¹ is a monodentate ligand bonded to M via an unshared electron pair of a hetero atom via a coordinating covalent bond, and Y ² is a unit price via a coordinating covalent bond An anionic sp ² carbon and a nitrogen atom are bonded to a monodentate ligand of M; and X ¹ to X ⁸ are a carbon atom or a hetero atom, and when one of X ¹ to X ⁸ is a carbon atom, and X ¹ X ⁸ to the binding of R ¹ to R ⁸ is a carbon atom bound to the substituent group, or when X ¹ to X ⁸ are one of nitrogen, oxygen or sulfur, and X ¹ to X ⁸ binding of R ¹ to R ⁸ is an unshared electron pair, or R ¹ to R ⁸ form a fused ring bonded to X ¹ to X ⁸ .

R ¹ to R ^{8 are} independently selected from the group consisting of hydrogen, substituted or unsubstituted aryl having 6 or more carbon numbers, substituted or unsubstituted having 2 or more carbon numbers a heteroaryl group, a substituted or unsubstituted alkyl group having 1 or more carbon numbers, a substituted or unsubstituted amine group having 2 or more carbon numbers, a substituted or unsubstituted carbon number having 1 or more carbon numbers Substituted alkoxy, halogen, nitro, substituted or unsubstituted extended aryl having 6 or more carbon numbers, substituted or unsubstituted heteroaryl having 2 or more carbon numbers, and having A substituted or unsubstituted alkyl group having one or more carbon numbers.

The compound of the above formula 1 is an aromatic cyclic compound.

The metal (M) forming the octahedral complex is ruthenium.

The substituent of R ¹ to R ⁸ may have a fluorene structure selected from the group consisting of the following formulas 2 and 3:

Wherein R ^{9 is} independently a group selected from the group consisting of hydrogen, halogen, R ¹¹ , OR ⁴ , N(R ¹¹ ) ₂ , P(R ¹¹ ) ₂ , P(OR ¹¹ ) ₂ , POR ¹¹ , PO ₂ R ¹¹ , PO ₃ R ¹¹ , SR ¹¹ , Si(R ¹¹ ) ₃ , Si(CH ₃ ) ₂ R ¹¹ , Si(Ph) ₂ R ¹¹ , B(R ¹¹ ) ₂ , B(OR ¹¹ ) ₂ , C(O)R ¹¹ , C(O)OR ¹¹ , C(O)N(R ¹¹ ) ₂ , CN, NO ₂ , SO ₂ , SOR ¹¹ , SO ₂ R ¹¹ and SO ₃ R ¹¹ ; R ¹¹ is selected from the group consisting of hydrogen, linear or branched C1 to C30 alkyl, linear or branched C2 to C30 alkenyl, linear or branched C2 to C30 alkynyl, linear or branched-chain C1 to C30 heteroalkyl group, C6 to C40 aryl and C3 to C40 heteroaryl group, wherein R ¹¹ substituent group with at least one substituent Z; Z group consisting of selected from the group consisting of following groups: R ^12, oR ¹² , N(R ¹² ) ₂ , P(R ¹² ) ₂ , P(OR ¹² ) ₂ , POR ¹² , PO ₂ R ¹² , PO ₃ R ¹² , SR ¹² , Si(R ¹² ) ₃ , Si(CH _{3 2} R ¹² , Si(Ph) ₂ R ¹² , B(R ¹² ) ₂ , B(OR ¹² ) ₂ , C(O)R ¹² , C(O)OR ¹² , C(O)N(R ¹² ) _{2, CN, NO 2, SO} 2, SOR 12, SO 2 R 12 , and SO ₃ R ^12; R ¹² each selected from the group consisting of the following group consisting Group: hydrogen, linear or branched C1 to C30 alkyl, linear or branched C2 to C30 alkenyl, linear or branched C2 to C30 alkynyl, straight or branched C1 to C30 heteroalkyl, C6 To a C40 aryl group and a C3 to C40 heteroaryl group; and R ¹⁰ is selected from the group consisting of substituted or unsubstituted aryl groups having 6 or more carbon numbers, having 2 or more carbon numbers a substituted or unsubstituted heteroaryl group, a substituted or unsubstituted alkyl group having 1 or more carbon numbers, a substituted or unsubstituted amine group having 2 or more carbon numbers, having 1 or more Substituted or unsubstituted alkoxy group, halogen, nitro group, substituted or unsubstituted aryl group having 6 or more carbon numbers, substituted or unsubstituted having 2 or more carbon numbers Heteroaryl, and substituted or unsubstituted alkyl having one or more carbon numbers.

According to a specific example, L is a ligand selected from the group consisting of the following ligands (1) to (9):

According to a specific example, the metal-substituted compound of the formula 1 above for the organic light-emitting display element may be a compound selected from the group consisting of the following formulas 1a to 1g, but is not limited to the compounds.

In the above formulae 1a to 1g, R and R' are independently a linear or branched C1 to C30 alkyl group, and M is a metal forming an octahedral complex.

An organic light emitting display element according to another specific example includes a first electrode disposed on a substrate, an organic thin layer containing a metal-miscible compound disposed on the first electrode, and a second electrode disposed on the organic thin layer.

The organic thin layer comprises at least one of the following layers: a first buffer layer disposed on the first electrode layer for hole injection or transmission, an emission layer disposed on the first buffer layer, and disposed on the emission layer A second buffer layer for electron injection or transmission.

The first electrode is formed of a transparent conductive metal oxide selected from the group consisting of ITO (indium tin oxide), IZO (indium zinc oxide), tin oxide, zinc oxide, and combinations thereof.

The substrate may be a glass substrate or a flexible substrate.

The emissive layer can be formed using at least one of spin coating, ink jet printing, and casting.

Detailed description

In the present specification, when a specific definition is not provided, "aryl" or "aryl" refers to a C6 to C40 aryl or an aryl group, and "heteroaryl" or "heteroaryl" means C2 to C40 heteroaryl or heteroaryl, "alkyl", "alkyl" or "alkoxy" means C1 to C30 alkyl, alkyl or alkoxy, and "heteroalkyl" means C1 to C30 heteroalkyl.

In the present specification, when a specific definition is not provided, the term "substituted" means at least one selected from the group consisting of an aryl group, a heteroaryl group, an alkyl group, an amine group, and an alkoxy group. a group substituted with a substituent of a group of halogens (F, CI, Br or I) and a nitro group.

In the present specification, the term "hetero" means a group containing from 1 to 10 hetero atoms selected from the group consisting of N, O, S and Si, when a specific definition is not provided.

The metal-substituted compound for an organic light-emitting display element comprises an asymmetric anthracene derivative ligand represented by the following formula 1:

Wherein n is an integer in the range of 1 to 3, and a and b are independently 0 or 1; the ring of Formula 1 above may be a ring containing a double bond or a single bond; M is an octahedral complex. a metal; L is a bidentate ligand bonded to a monovalent anion of M via a covalent covalent bond with a sp ² carbon and a hetero atom, or an unpaired electron pair of a hetero atom and a hetero atom via a coordinating covalent bond a monodentate ligand of a monovalent anion of M; Y ¹ is a monodentate ligand bonded to M via an unshared electron pair of a hetero atom via a coordinating covalent bond, and Y ² is a unit price via a coordinating covalent bond An anionic sp ² carbon and a nitrogen atom are bonded to a monodentate ligand of M; and X ¹ to X ⁸ are a carbon atom or a hetero atom, and when one of X ¹ to X ⁸ is a carbon atom, and X ¹ X ⁸ to the binding of R ¹ to R ⁸ is a carbon atom bound to the substituent group, or when one of X ¹ to X ⁸ as nitrogen, oxygen or sulfur, and X ¹ to X ⁸ binding of R ¹ to R ⁸ To form an fused ring that does not share an electron pair, or R ¹ to R ⁸ form a bond with X ¹ to X ⁸ .

R ¹ to R ^{8 are} independently selected from the group consisting of hydrogen, substituted or unsubstituted aryl having 6 or more carbon numbers, substituted or unsubstituted having 2 or more carbon numbers a heteroaryl group, a substituted or unsubstituted alkyl group having 1 or more carbon numbers, a substituted or unsubstituted amine group having 2 or more carbon numbers, a substituted or unsubstituted carbon number having 1 or more carbon numbers Substituted alkoxy, halogen, nitro, substituted or unsubstituted extended aryl having 6 or more carbon numbers, substituted or unsubstituted heteroaryl having 2 or more carbon numbers, and having A substituted or unsubstituted alkyl group having one or more carbon numbers.

The metal-missing compound comprises a 5-membered ring (when a and b are both 0), a 6-membered ring (when a=b=1), and a 5-membered ring and a 6-membered ring (when a=0 and b=1, Or a=1 and b=0).

The compound of the above formula 1 is an aromatic cyclic compound.

The metal (M) forming the octahedral complex is ruthenium.

The substituent of R ¹ to R ⁸ may have a fluorene structure selected from the group consisting of the following formulas 2 and 3:

Wherein R ^{9 is} independently a group selected from the group consisting of hydrogen, halogen, R ¹¹ , OR ⁴ , N(R ¹¹ ) ₂ , P(R ¹¹ ) ₂ , P(OR ¹¹ ) ₂ , _{^{POR 11, PO 2 R 11,}} PO 3 R 11, SR 11, Si (R 11) 3, Si (CH 3) 2 R 11, Si (Ph) 2 R 11, B (R 11) 2, B (OR ¹¹ ) ₂ , C(O)R ¹¹ , C(O)OR ¹¹ , C(O)N(R ¹¹ ) ₂ , CN, NO ₂ , SO ₂ , SOR ¹¹ , SO ₂ R ¹¹ and SO ₃ R ¹¹ ; R ¹¹ is selected from the group consisting of hydrogen, linear or branched C1 to C30 alkyl, linear or branched C2 to C30 alkenyl, linear or branched C2 to C30 alkynyl, linear or branched-chain C1 to C30 heteroalkyl group, C6 to C40 aryl group and a C6 to C40 heteroaryl group, wherein R ¹¹ substituent group with at least one substituent Z; Z group consisting of selected from the group consisting of following groups: R ^12, oR ¹² , N(R ¹² ) ₂ , P(R ¹² ) ₂ , P(OR ¹² ) ₂ , POR ¹² , PO ₂ R ¹² , PO ₃ R ¹² , SR ¹² , Si(R ¹² ) ₃ , Si(CH _{3 2} R ¹² , Si(Ph) ₂ R ¹² , B(R ¹² ) ₂ , B(OR ¹² ) ₂ , C(O)R ¹² , C(O)OR ¹² , C(O)N(R ¹² ) _{2, CN, NO 2, SO} 2, SOR 12, SO 2 R 12 , and SO ₃ R ^12; R ¹² each selected from the group consisting of the following group consisting Group: hydrogen, linear or branched C1 to C30 alkyl, linear or branched C2 to C30 alkenyl, linear or branched C2 to C30 alkynyl, straight or branched C1 to C30 heteroalkyl, C6 To a C40 aryl group and a C3 to C40 heteroaryl group; and R ¹⁰ is selected from the group consisting of substituted or unsubstituted aryl groups having 6 or more carbon numbers, having 2 or more carbon numbers a substituted or unsubstituted heteroaryl group, a substituted or unsubstituted alkyl group having one or more carbon numbers, a substituted or unsubstituted amino group having two or more carbon numbers, and one or more Substituted or unsubstituted alkoxy group, halogen, nitro group, substituted or unsubstituted aryl group having 6 or more carbon numbers, substituted or unsubstituted having 2 or more carbon numbers Heteroaryl, and substituted or unsubstituted alkyl having one or more carbon numbers.

According to a specific example, L is a ligand selected from the group consisting of the following ligands (1) to (9):

According to a specific example, the metal-substituted compound of the formula 1 above for the organic light-emitting display element may be a compound selected from the group consisting of the following formulas 1a to 1g, but is not limited to the compounds.

In the above formulas 1a to 1g, R is a linear or branched C1 to C30 alkyl group, and M is a metal forming an octahedral complex.

The above metal-doped compound can be used as an illuminating dopant for an organic light-emitting display element.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a view of an organic light emitting display element according to an embodiment of the present invention.

The organic light-emitting display element 1 according to a specific example includes a first electrode (anode, 20) disposed on the substrate 10, an organic thin layer 100 including a metal-misc compound disposed on the first electrode, and disposed on the organic thin layer 100. The second electrode (cathode, 30).

The organic thin layer 100 includes at least one of the following layers: a first buffer layer 110 disposed on the first electrode 20 for hole injection or transmission, an emission layer 120 disposed on the first buffer layer 110, and disposed on A second buffer layer 130 for electron injection or transmission on the emissive layer 120. At least one of the organic thin layers 100 comprises a metal-doped compound according to an embodiment of the present invention.

The first buffer layer 110 may include at least one selected from the group consisting of a hole injection layer (HIL) and a hole transport layer (HTL), and may further include an electron suppression layer to improve the light emitting characteristics of the emission layer 120.

The second buffer layer 130 may include at least one selected from the group consisting of an electron injection layer (EIL) and an electron transport layer (ETL), and may further include a hole suppression layer to improve the light emission characteristics of the emission layer 120.

A third buffer layer (not shown) may be disposed between the first electrode 20 and the first buffer layer 120 to supplement the anode surface and aid in hole injection and flow.

The third buffer layer may comprise a polymer such as doped polyaniline (PANI) or doped polyethylene dioxythiophene (PEDOT), or a low molecular material such as a-CuPc.

The first electrode 20 is formed of a transparent conductive metal oxide selected from the group consisting of ITO (indium tin oxide), IZO (indium zinc oxide), tin oxide, zinc oxide, and combinations thereof.

The substrate 10 can be a glass substrate or a flexible substrate.

The emissive layer 120 is formed from a host and a dopant using a wet process such as spin coating, ink jet printing or casting. The main body can be TMM038 (Merck, low molecular weight), PVK (polyvinylcarbazole) or PVK/CBP (4,4'-N, N'-dicarbazole biphenyl) (weight ratio of 45:55 or 1:1) And the dopant is a metal-doped compound according to an embodiment of the present invention. The metal-miscible compound may be included in an amount of from 1 to 30% by weight based on the total weight of the emissive layer material. In one embodiment, the metal-miscible compound can be included in an amount of from 3 to 10% by weight based on the total weight of the emissive layer material. Within the above range, preferred component characteristics are obtained.

When an electric field is applied to the organic light-emitting display element 1, holes and electrons are injected from the first electrode 20 and the second electrode 30, respectively. The injected holes and electrons recombine through the hole transport layer (HTL) and electron transport layer (ETL) on the emissive layer to provide luminescent excitons.

The provided illuminating excitons emit light by transitioning to the ground state.

The following examples illustrate the invention in more detail. However, it should be understood that the invention is not limited by the embodiments.

Example 1: Synthesis of Chemical Formula 1a'

14.0 g (1.1 equivalents, 61.1 mmol) of 1,3-dibromobenzene was dissolved in 200 ml of tetrahydrofuran. The reaction temperature was cooled to -78 °C, and then 39.8 ml (1.15 eq., 63.8 mmol) n-butyllithium (1.6 M in n-hexane) was slowly added dropwise.

After stirring for 30 minutes, 10.0 g (1.0 equivalent, 55.5 mmol) of anthrone in 100 ml of tetrahydrofuran was slowly added dropwise. The resulting mixture was stirred under nitrogen for 12 hours while allowing the reaction temperature to rise to room temperature.

When the reaction was completed, extraction with diethyl ether was carried out. The obtained organic layer was dried over anhydrous magnesium sulfate, concentrated, and then separated using a silica gel column chromatography to obtain 9-(3-bromophenyl)-9H-purin-9-ol.

5.0 g (1.0 equivalents, 14.8 mmol) of 9-(3-bromophenyl)-9H-indol-9-ol and 2.5 g (1.1 equivalents, 21.0 mmol) of 4-isobutylbenzene were dissolved in dichloromethane. . Subsequently, a catalytic amount of methanesulfonic acid diluted with dichloromethane was added dropwise to the solution. Stir the resulting product at room temperature 12 hour.

When the reaction was completed, the organic layer was extracted with dichloromethane, dried over anhydrous magnesium sulfate to concentrate, and then separated using a silica gel column chromatography to obtain 2-(3-(9-(4-isobutylphenyl). )-9H-fluoren-9-yl)phenyl) bromide.

4.0 g (1.0 eq., 8.8 mmol) of 3-(9-(4-isobutylphenyl)-9H-indol-9-yl)phenyl bromide was dissolved in 50 ml of THF. The solution was cooled to -78 ° C, and 9.73 ml (1.2 eq., 11 mmol) of n-butyllithium (1.6 M in hexane) was slowly added dropwise thereto.

The obtained product was stirred for 30 minutes, and 1.96 g (1.3 equivalent, 11.5 mmol) of 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2- was slowly added thereto in a dropwise manner. Diboron pentane. Subsequently, the resulting product was allowed to warm to room temperature and stirred for 12 hours.

When the reaction was completed, extraction with diethyl ether was carried out. The organic layer was dehydrated, concentrated and then separated using a silica gel column chromatography to afford Intermediate 3.

Next, a ligand is synthesized using a Suzuki coupling reaction. 2 g (1 equivalent, 4 mmol) of intermediate 3 and 0.59 g (0.9 eq., 3.6 mmol) of 1-chloroisoquinoline were dissolved in 10 ml of 2 M aqueous potassium carbonate and 20 ml of THF. Subsequently, 0.1 g (2 mol%) of ruthenium (triphenylphosphine)palladium having an oxidation number of 0 was added thereto under a nitrogen stream, and refluxed for 12 hours.

When the reaction was completed, hydrazine (triphenylphosphine) palladium was removed by performing diatomaceous earth filtration. Subsequently, the organic layer was extracted with diethyl ether. The organic layer was dehydrated, concentrated and then separated by column chromatography to obtain a ligand a.

0.46 g (4.5 equivalents, 0.9 mmol) of ligand a and 0.1 g (0.2 mmol) of ruthenium acetyl acetonate were added to the glycerol at 200 ° C in nitrogen Heat under air flow for 24 hours and then agitate.

When the reaction was completed, the reactants were placed in distilled water. Subsequently, the solid was filtered therefrom, dissolved in chloroform, and separated using a silica gel column chromatography to obtain a compound 1a' containing a complex anthracene derivative ligand as a bulky ligand.

Example 2: Synthesis of Chemical Formula 1b'

The intermediate 3 in Example 1 was reacted with 1-(4'-bromophenyl)isoquinoline to synthesize the corresponding ligand b using a Suzuki coupling reaction. According to the same method as in Example 1, a compound of the following formula 1b' was obtained using a ligand.

Example 3: Synthesis of Chemical Formula 1c'

The intermediate 3 in Example 1 was reacted with 1-(3'-bromophenyl)isoquinoline to synthesize the corresponding ligand c using a Suzuki coupling reaction. According to the same method as in Example 1, a compound of the following formula 1c' was obtained using a ligand.

Example 4: Synthesis of Chemical Formula 1d'

The intermediate 4 having the formula below is reacted with 1-(4'-bromophenyl)isoquinoline to synthesize the corresponding ligand d using a Suzuki coupling reaction. According to the same method as in Example 1, a compound of the following formula 1d' was obtained using a ligand.

Example 5: Synthesis of Chemical Formula 1e'

Intermediate 3 in Example 1 was reacted with 4-bromophenylpyridine to synthesize the corresponding ligand e using a Suzuki coupling reaction. According to the same method as in Example 1, a compound of the following formula 1e' was obtained using a ligand.

Example 6: Synthesis of Chemical Formula 1f'

The ligand f was prepared according to a method similar to that in Example 1. 0.3 g (2 equivalents, 0.66 mmol) of ligand f and 0.2 g (0.33 mmol) of Ir(ppy) ₂ (acac) were dissolved in glycerol. The resulting product was heated to 200 ° C for 24 hours under a stream of nitrogen and then agitated.

When the reaction was completed, the reactants were placed in distilled water. Subsequently, the solid was filtered therefrom, dissolved in chloroform, and then separated by a silica gel column chromatography to obtain a compound 1f' containing a complex anthracene derivative ligand as a bulky ligand.

Example 7: Synthesis of Chemical Formula 1g'

The ligand g was prepared according to a method similar to that in Example 1. 0.65 g (2 equivalents, 0.66 mmol) of ligand g and 0.2 g (0.33 mmol) of Ir(ppy) ₂ (acac) were dissolved in glycerol. The resulting product was heated to 200 ° C for 24 hours under a stream of nitrogen and then agitated.

When the reaction was completed, the reactants were placed in distilled water. Subsequently, the solid was filtered therefrom, dissolved in chloroform, and then separated by silica gel column chromatography to obtain a compound 1g' containing an asymmetric anthracene derivative ligand as a bulky ligand.

Example 8: Manufacture of OLED elements

The electroluminescent display element of Fig. 1 was prepared using the metal-substituted compounds 1a' to 1d' prepared according to Examples 1-4.

First, at 15 Ω/cm ² 1200 A first electrode 20 having a size of 20 mm × 20 mm × 0.7 mm was fabricated on a substrate 10 (Corning Inc.).

The first electrode 20 contains ITO (Indium Tin Oxide) as a transparent conductive metal oxide.

The substrate 10 containing the first electrode 20 was ultrasonicated for 5 minutes in isopropyl alcohol and pure water, and then UV ozone was cleaned for 30 minutes.

Subsequently, the first electrode 20 is coated on top of it to form the organic thin layer 100 by spin coating PEDOT (poly(ethylenedioxy)thiophene). Next, by using TMM038 (Merck, low molecular weight) as a host and metal-missing compounds 1a' to 1d' according to Examples 1 to 4 as a dopant (based on the total amount of the host and the dopant, 7 wt %), on PEDOT (poly(ethylenedioxy)thiophene), spin coating 500 Thick emission layer.

Next, on the emissive layer 120, BAIq is vacuum deposited to form 50 Thick hole suppression layer. Subsequently, on the hole suppression layer, Alq3 is vacuum deposited to form 200 Thick electron transport layer (ETL).

Subsequently, vacuum deposition 10 on the electron transport layer (ETL) LiF as an electron injection layer (EIL) and 1000 Al (cathode) to form a second electrode 30 having a LiF/AI metal, thereby fabricating the organic light-emitting display element 1.

Example 9: Manufacture of OLED elements

The organic light-emitting display element 1 shown in Fig. 1 was produced according to the same method as in Example 8, except that on PEDOT (poly(ethylenedioxy)thiophene), by using PVK/CBP (4, 4) '-N,N'-dicarbazole biphenyl) (weight ratio of 1:1) as a host and metal complex compounds 1e to 1g according to Examples 5 to 7 as dopants (in the form of a host and a dopant) Total, 7 wt%), spin coating 500 Thick emission layer.

By measuring the initial driving voltage (on voltage), driving voltage (V), current efficiency (cd/A), and electric power efficiency at each maximum brightness (cd/m ² ) and brightness of 1000 cd/m ² (Im/ W) The organic light-emitting display elements 1 according to Examples 8 and 9 were evaluated. The results of Example 8 are shown in Table 1.

As described above, the metal-doped compound according to an embodiment of the present invention contained in the organic thin layer 100 is not manufactured into the organic light-emitting display element 1 by spin coating as a wet method by vacuum deposition. However, the organic light emitting display element can emit pure red light having a color coordinate of x, y = [0.67, 0.33]. Further, measuring its initial driving voltage of 2.8-5.0 V, and the maximum luminance in the range of 3847 cd / m ² to 12,700 cd / m ^2. Therefore, it can have improved electrical stability.

In addition, by using Ir(piq) ₃ or Ir(piq) ₂ (acac) which is known to have an excellent effect in the metal-missing compound which emits red phosphorescence, due to the intermolecular van der Waals force (van der Waals' force is a metal-missing compound which has excellent solubility in an organic solvent such as toluene, chloroform, chlorobenzene or the like, and can be easily produced by a wet method.

In other words, when a bulky substituent is introduced into the metal-doped compound of the present invention, the metal-miscible compound can improve solubility because molecules therein become distant from each other, lowering crystallinity. The molecules have a suppressed interaction, which improves the luminous efficiency and electrical characteristics.

Therefore, the metal-substituted compound of the present invention can be suitably used as a phosphorescent material for an organic light-emitting display element.

The metal-knit compound for an organic light-emitting display element suppresses molecular interaction by introducing a bulky substituent as a ligand, resulting in improved solubility.

The metal-miscible compound can be applied to a wet method such as spin coating, inkjet printing, casting, or the like during the manufacture of the organic light-emitting display element, so that the manufacturing cost of the organic light-emitting display element is reduced.

Although the present invention has been described in connection with what is presently described as illustrative embodiments, it is understood that the invention is not limited to the specific examples disclosed, but rather, Various modifications and equivalent configurations within the scope.

1‧‧‧Organic light-emitting display elements

10‧‧‧Substrate

20‧‧‧First electrode or anode

30‧‧‧Second electrode or cathode

100‧‧‧Organic thin layer

110‧‧‧First buffer layer

120‧‧‧Emission layer

130‧‧‧Second buffer layer

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a view of an organic light emitting display element according to an embodiment of the present invention.

1‧‧‧Organic light-emitting display elements

10‧‧‧Substrate

20‧‧‧First electrode or anode

30‧‧‧Second electrode or cathode

100‧‧‧Organic thin layer

110‧‧‧First buffer layer

120‧‧‧Emission layer

130‧‧‧Second buffer layer

Claims (6)

A metal-substituted compound for an organic light-emitting display element, wherein the metal-knit compound for an organic light-emitting display element is a compound selected from the group consisting of the following formulas 1a to 1g, which includes an asymmetric anthracene derivative ligand : [Chemical Formula 1e] Here, in the above formulas 1a to 1g, R and R' are independently a linear or branched C1 to C30 alkyl group, and M is a metal forming an octahedral complex. An organic light emitting display element comprising: a first electrode disposed on a substrate; an organic thin layer disposed on the first electrode; and a second electrode disposed on the organic thin layer, wherein the organic thin layer includes A metal-missing compound of claim 1 of the patent scope. The organic light-emitting display device of claim 2, wherein the organic thin layer comprises at least one of the following layers: a first buffer layer disposed on the first electrode layer for hole injection or transmission, disposed in An emissive layer on the first buffer layer, and a second buffer layer disposed on the emissive layer for electron injection or transport. The organic light-emitting display element of claim 2, wherein the first electrode is formed of a transparent conductive metal oxide selected from the group consisting of ITO (indium tin oxide), IZO (indium zinc oxide), and combinations thereof. The organic light emitting display device of claim 2, wherein the substrate is a glass substrate or a flexible substrate. The organic light-emitting display element of claim 2, wherein the emission layer is formed using at least one of spin coating, inkjet printing, and casting.