KR20180103352A - Organic light emitting device - Google Patents

Abstract

The present invention provides an organic light emitting device with enhanced driving voltage, efficiency, and durability. The organic light emitting device comprises an anode; a cathode; a light emitting layer between the anode and the cathode; and an electron transport area between the cathode and the light emitting layer.

Description

[0001] The present invention relates to an organic light emitting device,

The present invention relates to an organic light emitting device having improved driving voltage, efficiency and lifetime.

In general, organic light emission phenomenon refers to a phenomenon in which an organic material is used to convert electric energy into light energy. The organic light emitting device using the organic light emitting phenomenon has a wide viewing angle, excellent contrast, fast response time, excellent characteristics of luminance, driving voltage and response speed, and much research has been conducted.

The organic light emitting device generally has a structure including an anode and a cathode, and an organic layer between the anode and the cathode. The organic material layer may have a multilayer structure composed of different materials in order to improve the efficiency and stability of the organic light emitting device. For example, the organic material layer may include a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer. When a voltage is applied between the two electrodes in the structure of such an organic light emitting device, holes are injected in the anode, electrons are injected into the organic layer in the cathode, excitons are formed when injected holes and electrons meet, When it falls back to the ground state, the light comes out.

In the organic light emitting device, development of an organic light emitting device having improved driving voltage, efficiency, and lifetime is continuously required.

Korean Patent Publication No. 10-2000-0051826

The present invention relates to an organic light emitting device having improved driving voltage, efficiency and lifetime.

The present invention provides the following organic light emitting device:

anode,

cathode,

A light-emitting layer between the anode and the cathode, and

And an electron transporting region between the cathode and the light emitting layer,

Wherein the light emitting layer comprises a compound represented by the following general formula (1)

Wherein the electron transport region comprises a compound represented by the following Formula 2:

[Chemical Formula 1]

In Formula 1,

X is O, or S,

L ₁ is a bond; Or substituted or unsubstituted C _6-60 arylene,

Ar ₁ is substituted or unsubstituted C _6-60 aryl,

Each R is independently selected from the group consisting of hydrogen; heavy hydrogen; halogen; Cyano; Nitro; Amino; Substituted or unsubstituted C _1-6 alkyl; Substituted or unsubstituted C _3-60 cycloalkyl; Substituted or unsubstituted C _2-60 alkenyl; Substituted or unsubstituted C _6-60 aryl; Or substituted or unsubstituted C _2-60 heteroaryl containing at least one hetero atom selected from the group consisting of N, O and S, at least one of R is deuterium,

n is an integer of 1 to 7,

(2)

In Formula 2,

L ₂ and L ₃ are each independently a bond; Or substituted or unsubstituted C _6-60 arylene,

Ar ₂ is substituted or unsubstituted C _6-60 aryl,

또는

이고,A is

or

ego,

R ₁ to R ₆ are each independently hydrogen; heavy hydrogen; halogen; Cyano; Nitro; Amino; Substituted or unsubstituted C _1-6 alkyl; Substituted or unsubstituted C _3-60 cycloalkyl; Substituted or unsubstituted C _2-60 alkenyl; Substituted or unsubstituted C _6-60 aryl; Or substituted or unsubstituted C _2-60 heteroaryl containing at least one hetero atom selected from the group consisting of N, O and S.

The organic light emitting device described above is excellent in driving voltage, efficiency, and lifetime.

1 shows an example of an organic light-emitting device comprising a substrate 1, an anode 2, a light-emitting layer 3, an electron-transporting region 4, and a cathode 5.
2 shows an example of an organic light emitting element made up of a substrate 1, an anode 2, a light emitting layer 3, a hole blocking layer 6, an electron transport layer 7, and a cathode 5.
3 shows an example of an organic light emitting element comprising a substrate 1, an anode 2, a hole transporting layer 8, a light emitting layer 3, a hole blocking layer 6, an electron transporting layer 7 and a cathode 5 FIG.

Hereinafter, the present invention will be described in detail in order to facilitate understanding of the present invention.

는 다른 치환기에 연결되는 결합을 의미한다. In the present specification,

Quot; means a bond connected to another substituent.

As used herein, the term " substituted or unsubstituted " A halogen group; Cyano; A nitro group; A hydroxy group; A carbonyl group; An ester group; Imide; An amino group; Phosphine oxide groups; An alkoxy group; An aryloxy group; An alkyloxy group; Arylthioxy group; An alkylsulfoxy group; Arylsulfoxy group; Silyl group; Boron group; An alkyl group; Cycloalkyl groups; An alkenyl group; An aryl group; Aralkyl groups; An aralkenyl group; An alkylaryl group; An alkylamine group; An aralkylamine group; A heteroarylamine group; An arylamine group; Arylphosphine groups; Or a heteroaryl group containing at least one of N, O and S atoms, or a substituted or unsubstituted group in which at least two of the above-exemplified substituents are connected to one another . For example, "the substituent to which at least two substituents are connected" may be a biphenylyl group. That is, the biphenylyl group may be an aryl group, and may be interpreted as a substituent in which two phenyl groups are connected.

In the present specification, the carbon number of the carbonyl group is not particularly limited, but it is preferably 1 to 40 carbon atoms. Specifically, it may be a compound having the following structure, but is not limited thereto.

In the present specification, the ester group may be substituted with a straight-chain, branched or cyclic alkyl group having 1 to 25 carbon atoms or an aryl group having 6 to 25 carbon atoms in the ester group. Specifically, it may be a compound of the following structural formula, but is not limited thereto.

In the present specification, the number of carbon atoms of the imide group is not particularly limited, but is preferably 1 to 25 carbon atoms. Specifically, it may be a compound having the following structure, but is not limited thereto.

In the present specification, the silyl group specifically includes a trimethylsilyl group, a triethylsilyl group, a t-butyldimethylsilyl group, a vinyldimethylsilyl group, a propyldimethylsilyl group, a triphenylsilyl group, a diphenylsilyl group, But are not limited thereto.

In the present specification, the boron group specifically includes, but is not limited to, a trimethylboron group, a triethylboron group, a t-butyldimethylboron group, a triphenylboron group, and a phenylboron group.

In the present specification, examples of the halogen group include fluorine, chlorine, bromine or iodine.

In the present specification, the alkyl group may be linear or branched, and the number of carbon atoms is not particularly limited, but is preferably 1 to 40. According to one embodiment, the alkyl group has 1 to 20 carbon atoms. According to another embodiment, the alkyl group has 1 to 10 carbon atoms. According to another embodiment, the alkyl group has 1 to 6 carbon atoms. Specific examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a tert-butyl group, But are not limited to, pentyl, isopentyl, neopentyl, tert-pentyl, hexyl, n-hexyl, 1-methylpentyl, , n-heptyl, 1-methylhexyl, cyclopentylmethyl, cyclohexylmethyl, octyl, n-octyl, tert-octyl, 1-methylheptyl, But are not limited to, dimethylheptyl, 1-ethyl-propyl, 1,1-dimethyl-propyl, isohexyl, 2-methylpentyl, 4-methylhexyl and 5-methylhexyl.

In the present specification, the alkenyl group may be straight-chain or branched, and the number of carbon atoms is not particularly limited, but is preferably 2 to 40. According to one embodiment, the alkenyl group has 2 to 20 carbon atoms. According to another embodiment, the alkenyl group has 2 to 10 carbon atoms. According to another embodiment, the alkenyl group has 2 to 6 carbon atoms. Specific examples include vinyl, 1-propenyl, isopropenyl, 1-butenyl, 2-butenyl, 3-butenyl, 1-pentenyl, Butenyl, allyl, 1-phenylvinyl-1-yl, 2-phenylvinyl-1-yl, (Diphenyl-1-yl) vinyl-1-yl, stilbenyl, stilenyl, and the like.

In the present specification, the cycloalkyl group is not particularly limited, but preferably has 3 to 60 carbon atoms. According to one embodiment, the cycloalkyl group has 3 to 30 carbon atoms. According to another embodiment, the cycloalkyl group has 3 to 20 carbon atoms. According to another embodiment, the cycloalkyl group has 3 to 6 carbon atoms. Specific examples include cyclopropyl, cyclobutyl, cyclopentyl, 3-methylcyclopentyl, 2,3-dimethylcyclopentyl, cyclohexyl, 3-methylcyclohexyl, 4-methylcyclohexyl, 2,3- 4,5-trimethylcyclohexyl, 4-tert-butylcyclohexyl, cycloheptyl, cyclooctyl, and the like, but are not limited thereto.

In the present specification, the aryl group is not particularly limited, but preferably has 6 to 60 carbon atoms, and may be a monocyclic aryl group or a polycyclic aryl group. According to one embodiment, the aryl group has 6 to 30 carbon atoms. According to one embodiment, the aryl group has 6 to 20 carbon atoms. The aryl group may be a phenyl group, a biphenyl group, a terphenyl group or the like as the monocyclic aryl group, but is not limited thereto. Examples of the polycyclic aryl group include, but are not limited to, a naphthyl group, an anthracenyl group, a phenanthryl group, a pyrenyl group, a perylenyl group, a klycenyl group and a fluorenyl group.

등이 될 수 있다. 다만, 이에 한정되는 것은 아니다.In the present specification, a fluorenyl group may be substituted, and two substituents may be bonded to each other to form a spiro structure. When the fluorenyl group is substituted,

And the like. However, the present invention is not limited thereto.

In the present specification, the heteroaryl group is a heteroaryl group containing at least one of O, N, Si and S as a hetero atom. The number of carbon atoms is not particularly limited, but is preferably 2 to 60 carbon atoms. Examples of the heteroaryl group include a thiophene group, a furane group, a furyl group, an imidazole group, a thiazole group, an oxazole group, an oxadiazole group, a triazole group, a pyridyl group, a bipyridyl group, a pyrimidyl group, An acyl group, an acridinyl group, a pyridazinyl group, a pyrazinyl group, a quinolinyl group, a quinazolinyl group, a quinoxalinyl group, a phthalazinyl group, a pyridopyrimidinyl group, a pyridopyranyl group, a pyrazinopyranyl group, , An indole group, a carbazole group, a benzooxazole group, a benzoimidazole group, a benzothiazole group, a benzocarbazole group, a benzothiophene group, a dibenzothiophene group, a benzofuranyl group, a phenanthroline, An isoxazolyl group, an oxadiazolyl group, a thiadiazolyl group, a benzothiazolyl group, a phenothiazinyl group, and a dibenzofuranyl group, but is not limited thereto.

In the present specification, the aryl group in the aralkyl group, the aralkenyl group, the alkylaryl group and the arylamine group is the same as the aforementioned aryl group. In the present specification, the alkyl group in the aralkyl group, the alkylaryl group, and the alkylamine group is the same as the alkyl group described above. In this specification, the heteroaryl among the heteroarylamines can be applied to the description of the above-mentioned heteroaryl groups. In the present specification, the alkenyl group in the aralkenyl group is the same as the above-mentioned alkenyl group. In the present specification, the description of the aryl group described above can be applied except that arylene is a divalent group. In this specification, the description of the above-mentioned heteroaryl group can be applied except that the heteroarylene is a divalent group. In the present specification, the description of the above-mentioned aryl group or cycloalkyl group can be applied except that the hydrocarbon ring is not a monovalent group and two substituents are bonded to each other.

Hereinafter, the present invention will be described in detail with respect to each constitution.

Anode and cathode

The positive electrode and the negative electrode used in the present invention refer to an electrode used in an organic light emitting device.

As the anode material, a material having a large work function is preferably used so that hole injection can be smoothly conducted to the organic material layer. Specific examples of the positive electrode material include metals such as vanadium, chromium, copper, zinc, and gold, or alloys thereof; Metal oxides such as zinc oxide, indium oxide, indium tin oxide (ITO), and indium zinc oxide (IZO); ZnO: Al or SNO _2: a combination of a metal and an oxide such as Sb; Conductive polymers such as poly (3-methylthiophene), poly [3,4- (ethylene-1,2-dioxy) thiophene] (PEDOT), polypyrrole and polyaniline.

The negative electrode material is preferably a material having a small work function to facilitate electron injection into the organic material layer. Specific examples of the negative electrode material include metals such as magnesium, calcium, sodium, potassium, titanium, indium, yttrium, lithium, gadolinium, aluminum, silver, tin and lead or alloys thereof; Layer structure materials such as LiF / Al or LiO ₂ / Al, but are not limited thereto.

Hole injection layer

The organic light emitting device according to the present invention may further include a hole injection layer between the anode and a hole transport layer to be described later.

The hole injecting layer is a layer for injecting holes from an electrode. The hole injecting material has a hole injecting effect, and has a hole injecting effect on the light emitting layer or a light emitting material. A compound which prevents the migration of excitons to the electron injecting layer or the electron injecting material and is also excellent in the thin film forming ability is preferable. It is preferred that the highest occupied molecular orbital (HOMO) of the hole injecting material be between the work function of the anode material and the HOMO of the surrounding organic layer.

Specific examples of the hole injecting material include metal porphyrin, oligothiophene, arylamine-based organic materials, hexanitrile hexaazatriphenylene-based organic materials, quinacridone-based organic materials, and perylene- , Anthraquinone, polyaniline and polythiophene-based conductive polymers, but the present invention is not limited thereto.

Hole transport region

The hole transporting region used in the present invention means a region for receiving holes from the hole injection layer formed on the anode or anode and transporting holes to the light emitting layer.

The hole transporting region includes a hole transporting layer, or includes a hole transporting layer and an electron blocking layer. When the hole transporting region includes a hole transporting layer and an electron blocking layer, preferably, the light emitting layer and the electron blocking layer are adjacent to each other.

The hole transporting material contained in the hole transporting region is a material capable of transporting holes from the anode or the hole injecting layer to the light emitting layer.

Specific examples of the hole transporting material include an arylamine-based organic material, a conductive polymer, and a block copolymer having a conjugated portion and a non-conjugated portion together, but the present invention is not limited thereto.

The light-

The light emitting layer used in the present invention is a layer capable of emitting light in the visible light region by combining holes and electrons transferred from the anode and the cathode, and is preferably a material having good quantum efficiency for fluorescence or phosphorescence.

Generally, the light emitting layer includes a host material and a dopant material, and the present invention includes a compound represented by the above formula (1) as a host.

In Formula 1, L ₁ is a bond; Phenylene; Or naphthylene.

Also, Ar ₁ may be C _6-20 aryl.

Specifically, Ar ₁ can be phenyl, biphenyl, naphthyl, phenanthrenyl, or triphenylenyl.

Also, each R may independently be hydrogen, deuterium, or C _6-20 aryl. For example, each R may independently be hydrogen, deuterium, phenyl, biphenyl, or naphthyl.

Also, n may be 1, 2, 3, 4, or 7. In this case, n represents the number of R, and when n is 2 or more, 2 or more Rs may be the same or different from each other.

Representative examples of the compound represented by the above formula (1) are as follows:

The compound represented by the formula (1) can be prepared by the following reaction scheme (1).

[Reaction Scheme 1]

In Reaction Scheme 1, L ₁ , Ar ₁ , R and n are the same as defined in Formula 1 above.

The above reaction uses a Suzuki coupling reaction, which can be further specified in Examples to be described later.

The dopant material is not particularly limited as long as it is a material used in an organic light emitting device. Examples thereof include aromatic amine derivatives, styrylamine compounds, boron complexes, fluoranthene compounds, and metal complexes. Specific examples of the aromatic amine derivatives include condensed aromatic ring derivatives having substituted or unsubstituted arylamino groups, and examples thereof include pyrene, anthracene, chrysene, and peripherrhene having an arylamino group. Examples of the styrylamine compound include substituted or unsubstituted Wherein at least one aryl vinyl group is substituted with at least one aryl vinyl group, and at least one substituent selected from the group consisting of an aryl group, a silyl group, an alkyl group, a cycloalkyl group and an arylamino group is substituted or unsubstituted. Specific examples thereof include, but are not limited to, styrylamine, styryldiamine, styryltriamine, styryltetraamine, and the like. Examples of the metal complex include iridium complex, platinum complex, and the like, but are not limited thereto.

Electron transport area

The electron transporting region used in the present invention means a region that receives electrons from the electron injection layer formed on the cathode or the cathode and transports electrons to the emission layer and also inhibits the transfer of holes from the emission layer.

The electron transporting region includes an electron transporting layer, or includes an electron transporting layer and a hole blocking layer. When the electron transporting region includes an electron transporting layer and a hole blocking layer, preferably, the light emitting layer and the hole blocking layer are adjacent to each other. Therefore, the electron transporting region includes an electron transporting layer, the electron transporting layer includes the compound represented by Formula 2, or the electron transporting region includes an electron transporting layer and a hole blocking layer, And a compound represented by the formula (2).

In Formula 2, L ₂ and L ₃ may each independently be a bond, phenylene, or naphthylene.

Specifically, L ₂ is a bond, phenylene, or naphthylene, and L ₃ may be a bond or phenylene.

Ar ₂ can also be C _6-20 aryl.

Specifically, Ar ₂ may be phenyl, biphenyl, naphthyl, or phenanthrenyl.

Also, R ₁ to R ₆ each independently may be hydrogen, C _1-10 alkyl, or C _6-20 aryl.

Specifically, R ₁ to R ₆ each independently may be hydrogen, methyl, ethyl, or phenyl.

Specifically, for example, R ₁ and R ₂ are each independently methyl, ethyl, or phenyl, and R ₃ to R ₆ may be hydrogen.

Representative examples of the compound represented by the general formula (2) are as follows:

Electron injection layer

The organic light emitting device according to the present invention may further include an electron injection layer between the electron transport layer and the cathode. The electron injection layer is a layer for injecting electrons from the electrode. The electron injection layer has the ability to transport electrons, has an electron injection effect from the cathode, and has an excellent electron injection effect with respect to the light emitting layer or the light emitting material. A compound which prevents migration to a layer and is excellent in a thin film forming ability is preferable.

Specific examples of materials that can be used for the electron injection layer include fluorenone, anthraquinodimethane, diphenoquinone, thiopyran dioxide, oxazole, oxadiazole, triazole, imidazole, perylene tetracarboxylic acid, Anthrone, and derivatives thereof, metal complex compounds, and nitrogen-containing 5-membered ring derivatives, but are not limited thereto.

Examples of the metal complex compound include 8-hydroxyquinolinato lithium, bis (8-hydroxyquinolinato) zinc, bis (8-hydroxyquinolinato) copper, bis (8- Tris (8-hydroxyquinolinato) aluminum, tris (2-methyl-8-hydroxyquinolinato) aluminum, tris (8- hydroxyquinolinato) gallium, bis (10- Quinolinato) beryllium, bis (10-hydroxybenzo [h] quinolinato) zinc, bis (2-methyl-8- quinolinato) chlorogallium, bis (2-methyl-8-quinolinato) (2-naphtholato) gallium, and the like, But is not limited thereto.

Organic light emitting device

The structure of the organic light emitting device according to the present invention is illustrated in FIG. 1 shows an example of an organic light-emitting device comprising a substrate 1, an anode 2, a light-emitting layer 3, an electron-transporting region 4, and a cathode 5. 2 shows an example of an organic light emitting element made up of a substrate 1, an anode 2, a light emitting layer 3, a hole blocking layer 6, an electron transport layer 7, and a cathode 5. 3 shows an example of an organic light emitting element comprising a substrate 1, an anode 2, a hole transporting layer 8, a light emitting layer 3, a hole blocking layer 6, an electron transporting layer 7 and a cathode 5 FIG.

The organic light emitting device according to the present invention can be manufactured by sequentially laminating the above-described structures. At this time, a metal or a metal oxide having conductivity or an alloy thereof is deposited on the substrate using a PVD (physical vapor deposition) method such as sputtering or e-beam evaporation to form an anode Forming each of the above-described layers thereon, and then depositing a material usable as a negative electrode thereon. In addition to such a method, an organic light emitting device can be formed by sequentially depositing a cathode material, an organic material layer, and a cathode material on a substrate. Further, the light emitting layer can be formed by a solution coating method as well as a vacuum deposition method for the host and the dopant. Here, the solution coating method refers to spin coating, dip coating, doctor blading, inkjet printing, screen printing, spraying, roll coating and the like, but is not limited thereto.

In addition to such a method, an organic light emitting device can be manufactured by sequentially depositing an organic material layer and a cathode material from a cathode material on a substrate (WO 2003/012890). However, the manufacturing method is not limited thereto.

Meanwhile, the organic light emitting diode according to the present invention may be a front emission type, a back emission type, or a both-sided emission type, depending on the material used.

Hereinafter, preferred embodiments of the present invention will be described in order to facilitate understanding of the present invention. However, the following examples are provided only for the purpose of easier understanding of the present invention, and the present invention is not limited thereto.

Example 1

Example 1-1

A thin glass substrate coated with ITO (Indium Tin Oxide) at a thickness of 1,400 Å was immersed in distilled water containing detergent and washed with ultrasonic waves. In this case, Fischer Co. was used as a detergent, and distilled water filtered by a filter of Millipore Co. was used as distilled water. The ITO was washed for 30 minutes and then washed twice with distilled water and ultrasonically cleaned for 10 minutes. After the distilled water was washed, it was ultrasonically washed with a solvent of isopropyl alcohol, acetone, and methanol, dried, and then transported to a plasma cleaner. Further, the substrate was cleaned using oxygen plasma for 5 minutes, and then the substrate was transported by a vacuum evaporator.

The following compound HI-A and hexanitrile hexaazatriphenylene (HAT) were sequentially deposited on the ITO transparent electrode in a thickness of 650 angstroms and 50 angstroms, respectively, to form a hole injection layer.

Compound HT-A shown below was vacuum-deposited as a hole transporting layer to a thickness of 600 Å, and then HT-B was thermally vacuum-deposited to a thickness of 50 Å as an electron blocking layer.

Subsequently, the host compound 1-1 and the dopant compound BD of 4 wt% as the light emitting layer were vacuum deposited to a thickness of 200 Å.

Subsequently, the following compound 2-1 and Liq were thermally vacuum-deposited in a thickness of 360 Å at a ratio of 1: 1 as an electron transporting layer and an electron injecting layer, and then Liq was vacuum-deposited to a thickness of 5 Å.

Magnesium and silver were sequentially deposited on the electron injection layer at a ratio of 10: 1 to a thickness of 220 ANGSTROM and aluminum to a thickness of 1000 ANGSTROM to form a cathode, thereby preparing an organic light emitting device.

Example  1-2 Example  1-9 and Comparative Example  1-1 to Comparative Example  1-6

Examples 1-2 to 1-9 and Comparative Examples 1-1 to Comparative Example were prepared in the same manner as in Example 1-1, except that the host material and the electron transport layer material were changed as shown in Table 1 below. Each of the organic luminescent devices of Examples 1-6 was fabricated.

Experimental Example  One

The voltage, efficiency, color coordinates and lifetime (T90) were measured by applying current to the organic light emitting devices fabricated in Examples 1-1 to 1-9 and Comparative Examples 1-1 to 1-6, Respectively. At this time, the voltage, efficiency and color coordinates were measured by applying a current density of 10 mA / cm ² , and T90 means the time until the initial luminance dropped to 90% at a current density of 20 mA / cm ² .

Host
matter Electron transport layer
matter @ 10 mA / cm ² @ 20 mA / cm ² Voltage
(V) efficiency
(cd / A) CIE-x CIE-y life span
(T90, hr) Example 1-1 Compound 1-1 Compound 2-1 3.31 5.61 0.138 0.130 170 Examples 1-2 Compound 1-1 Compound 2-2 3.35 5.51 0.138 0.130 160 Example 1-3 Compound 1-1 Compound 2-3 3.33 5.52 0.139 0.130 160 Examples 1-4 Compound 1-2 Compound 2-1 3.36 5.48 0.138 0.131 150 Examples 1-5 Compound 1-2 Compound 2-2 3.31 5.52 0.138 0.130 140 Examples 1-6 Compound 1-3 Compound 2-1 3.28 5.57 0.138 0.130 150 Examples 1-7 Compound 1-3 Compound 2-3 3.47 5.58 0.138 0.130 180 Examples 1-8 Compound 1-4 Compound 2-2 3.36 5.57 0.138 0.131 160 Examples 1-9 Compound 1-4 Compound 2-3 3.42 5.51 0.138 0.130 140 Comparative Example 1-1 BH-A ET-A 3.91 4.83 0.138 0.131 120 Comparative Example 1-2 BH-A Compound 2-1 4.57 4.21 0.139 0.136 70 Comparative Example 1-3 BH-B Compound 2-2 4.70 4.38 0.140 0.138 60 Comparative Example 1-4 BH-C Compound 2-3 4.67 4.33 0.138 0.139 60 Comparative Example 1-5 Compound 1-1 ET-A 5.34 4.04 0.139 0.140 20 Comparative Example 1-6 Compound 1-2 ET-B 5.48 3.99 0.142 0.138 20

As can be seen from the above Table 1, in the organic light emitting device manufactured by combining the compound of Formula 1 of the present invention as a host material and the compound of Formula 2 as an electron transporting material, compared with the organic light emitting device of Comparative Example, Voltage, current efficiency and life span.

Example  2

Example  2-1

A thin glass substrate coated with ITO (Indium Tin Oxide) at a thickness of 1,400 Å was immersed in distilled water containing detergent and washed with ultrasonic waves. In this case, Fischer Co. was used as a detergent, and distilled water filtered by a filter of Millipore Co. was used as distilled water. The ITO was washed for 30 minutes and then washed twice with distilled water and ultrasonically cleaned for 10 minutes. After the distilled water was washed, it was ultrasonically washed with a solvent of isopropyl alcohol, acetone, and methanol, dried, and then transported to a plasma cleaner. Further, the substrate was cleaned using oxygen plasma for 5 minutes, and then the substrate was transported by a vacuum evaporator.

On the prepared ITO transparent electrode, the following compounds HI-A and HAT were sequentially deposited by thermal vacuum deposition to a thickness of 650 ANGSTROM and 50 ANGSTROM, respectively, to form a hole injection layer. HT-A was vacuum-deposited as a hole transport layer thereon to a thickness of 600 Å, and then HT-B was thermally vacuum deposited to a thickness of 50 Å as an electron blocking layer.

Subsequently, a host compound 1-1 and a dopant compound BD of 4 wt% were vacuum deposited as a light emitting layer to a thickness of 200 Å.

Subsequently, Compound 2-1 was vacuum-deposited to a thickness of 50 ANGSTROM as a hole blocking layer. A 1: 1 ratio of 4,7-diphenyl-1,10-phenanthroline (Bphen) and Liq was deposited on the hole blocking layer to a thickness of 310 Å by thermal vacuum deposition Then, Liq was vacuum-deposited to a thickness of 5 Å to form an electron transport layer and an electron injection layer.

Magnesium and silver were sequentially deposited on the electron injection layer at a ratio of 10: 1 to a thickness of 220 ANGSTROM and aluminum to a thickness of 1000 ANGSTROM to form a cathode, thereby preparing an organic light emitting device.

Examples 2-2 to 2-9 and Comparative Examples 2-1 to 2-6

Examples 2-2 to 2-9 and Comparative Examples 2-1 to 2-3 were prepared in the same manner as in Example 2-1, except that the host material and the hole blocking layer material were changed as shown in Table 2 below. The organic light emitting devices of Comparative Examples 2-6 were fabricated.

Experimental Example 2

The voltage, efficiency, color coordinates and lifetime (T90) were measured by applying currents to the organic light-emitting devices fabricated in Examples 2-1 to 2-9 and Comparative Examples 2-1 to 2-6, Respectively. At this time, the voltage, efficiency and color coordinates were measured by applying a current density of 10 mA / cm ² , and T90 means the time until the initial luminance dropped to 90% at a current density of 20 mA / cm ² .

Host
matter Hole blocking layer
matter @ 10 mA / cm ² @ 20 mA / cm ² Voltage
(V) efficiency
(cd / A) CIE-x CIE-y life span
(T90, hr) Example 2-1 Compound 1-1 Compound 2-1 3.27 5.41 0.137 0.130 170 Example 2-2 Compound 1-1 Compound 2-2 3.24 5.50 0.139 0.131 160 Example 2-3 Compound 1-1 Compound 2-3 3.21 5.47 0.138 0.130 160 Examples 2-4 Compound 1-2 Compound 2-1 3.21 5.41 0.138 0.131 150 Example 2-5 Compound 1-2 Compound 2-2 3.27 5.48 0.138 0.130 170 Examples 2-6 Compound 1-3 Compound 2-1 3.25 5.39 0.138 0.131 150 Examples 2-7 Compound 1-3 Compound 2-3 3.26 5.46 0.139 0.131 180 Examples 2-8 Compound 1-4 Compound 2-2 3.22 5.38 0.138 0.130 160 Examples 2-9 Compound 1-4 Compound 2-3 3.24 5.46 0.137 0.130 150 Comparative Example 2-1 BH-A ET-A 3.75 4.83 0.138 0.130 130 Comparative Example 2-2 BH-A Compound 2-1 4.35 4.50 0.140 0.130 90 Comparative Example 2-3 BH-B Compound 2-2 4.33 4.39 0.138 0.131 60 Comparative Example 2-4 BH-C Compound 2-3 4.38 4.50 0.139 0.131 80 Comparative Example 2-5 Compound 1-1 ET-A 4.57 4.67 0.138 0.136 40 Comparative Example 2-6 Compound 1-2 ET-B 4.60 4.15 0.140 0.135 10

As can be seen from the above Table 2, in the case of the organic light emitting device manufactured by combining the compound of Formula 1 of the present invention with the host material and the compound of Formula 2 with the hole blocking material, Voltage, current efficiency and life span.

Therefore, as can be seen from Tables 1 and 2, when the compound of Formula 2 of the present invention is used not only as a material for an electron transport layer but also as a material for a hole blocking layer, The voltage, efficiency and lifetime of the organic light emitting device are improved.

1: substrate 2: anode
3: light emitting layer 4: electron transporting region
5: cathode 6: hole blocking layer
7: electron transport layer 8: hole transport layer

Claims (15)

anode,
cathode,
A light-emitting layer between the anode and the cathode, and
And an electron transporting region between the cathode and the light emitting layer,
Wherein the light emitting layer comprises a compound represented by the following general formula (1)
Wherein the electron transporting region comprises a compound represented by the following formula (2)
Organic Light Emitting Device:
[Chemical Formula 1]

In Formula 1,
X is O, or S,
L ₁ is a bond; Or substituted or unsubstituted C _6-60 arylene,
Ar ₁ is substituted or unsubstituted C _6-60 aryl,
Each R is independently selected from the group consisting of hydrogen; heavy hydrogen; halogen; Cyano; Nitro; Amino; Substituted or unsubstituted C _1-6 alkyl; Substituted or unsubstituted C _3-60 cycloalkyl; Substituted or unsubstituted C _2-60 alkenyl; Substituted or unsubstituted C _6-60 aryl; Or substituted or unsubstituted C _2-60 heteroaryl containing at least one hetero atom selected from the group consisting of N, O and S, at least one of R is deuterium,
n is an integer of 1 to 7,
(2)

In Formula 2,
L ₂ and L ₃ are each independently a bond; Or substituted or unsubstituted C _6-60 arylene,
Ar ₂ is substituted or unsubstituted C _6-60 aryl,
A is

or

ego,
R ₁ to R ₆ are each independently hydrogen; heavy hydrogen; halogen; Cyano; Nitro; Amino; Substituted or unsubstituted C _1-6 alkyl; Substituted or unsubstituted C _3-60 cycloalkyl; Substituted or unsubstituted C _2-60 alkenyl; Substituted or unsubstituted C _6-60 aryl; Or substituted or unsubstituted C _2-60 heteroaryl containing at least one hetero atom selected from the group consisting of N, O and S.
The method according to claim 1,
L ₁ is a bond; Phenylene; Or naphthylene.
The method according to claim 1,
Ar ₁ is phenyl, biphenyl, naphthyl, phenanthrenyl, or triphenylenyl.
The method according to claim 1,
Wherein each R is independently hydrogen, deuterium, or C _6-20 aryl.
The method according to claim 1,
and n is 1, 2, 3, 4, or 7.
The method according to claim 1,
Wherein the compound represented by Formula 1 is any one selected from the group consisting of:

The method according to claim 1,
L ₂ and L ₃ are each independently a bond, phenylene, or naphthylene.
8. The method of claim 7,
L ₂ is a bond, phenylene, or naphthylene,
And L < ₃ > is a bond or phenylene.
The method according to claim 1,
And Ar < ₂ > is phenyl, biphenyl, naphthyl, or phenanthrenyl.
The method according to claim 1,
R ₁ to R ₆ are each independently hydrogen, methyl, ethyl, or phenyl.
11. The method of claim 10,
R ₁ and R ₂ are each independently methyl, ethyl, or phenyl,
And R ₃ to R ₆ are hydrogen.
The method according to claim 1,
Wherein the compound represented by Formula 2 is any one selected from the group consisting of:

The method according to claim 1,
Wherein the electron transporting region comprises an electron transporting layer,
Wherein the electron transporting layer comprises a compound represented by the general formula (2)
Organic light emitting device.
The method according to claim 1,
Wherein the electron transporting region includes an electron transporting layer and a hole blocking layer,
Wherein the hole blocking layer comprises a compound represented by the general formula (2)
Organic light emitting device.
15. The method of claim 14,
Wherein the light emitting layer and the hole blocking layer are adjacent to each other,
Organic light emitting device.

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