KR100587291B1 - Red Organic Luminous Material And Organic Electroluminescent Display Device Using The Same - Google Patents

Abstract

The red organic light emitting material and the electroluminescent device using the red organic light emitting material of the present invention provides an organic light emitting material having both a hole transport characteristic, an electron transport characteristic and a red light emission characteristic under an electric field, and the organic light emitting material as a light emitting layer It is characterized by providing a red organic light emitting display device having excellent efficiency, high brightness and color purity unlike when using a conventional light emitting material.

Organic light emitting device, organic light emitting layer, red light emitting, hole, electron, high brightness, high efficiency

Description

Red Organic Luminous Material And Organic Electroluminescent Display Device Using The Same}

1 is a structural diagram of a conventional organic light emitting display device.

2 is a structural diagram of an organic light emitting display device according to the present invention;

3 is a structural diagram of another organic light emitting display device according to the present invention;

4 is a structural diagram of another organic light emitting display device of the present invention.

* Explanation of symbols for main parts of the drawings

200, 300, 400: transparent substrate 201, 301, 401: anode

202, 302,: hole injection layer 203: hole transport layer

204, 304, 404: organic light emitting layer 205: electron transport layer

206, 306: electron injection layer 207, 307, 407: cathode

The present invention relates to an organic light emitting device that emits red light under an electric field and an organic electroluminescent device (OELD) using the red organic light emitting material, and more particularly, to an organic light emitting device having high brightness and high efficiency.

That is, the present invention relates to an organic light emitting device having both a hole transporting capability and an electron transporting capability, and capable of emitting red light and a high brightness and high efficiency organic electroluminescent device manufactured using the red organic light emitting material.

Organic electroluminescent display devices (OLEDs) have recently been used in flat panel displays since Pope, Kalman and Magnate discovered electroluminescence in anthracene single crystals in 1963. Organic electroluminescent devices using organic electroluminescent devices are being developed very rapidly such as improved performance as displays and application products.

In terms of performance improvement, the organic light emitting display device has the following advantages over LCD or PDP, which is a flat panel display device, according to IEEE Spectrum 35 (4), 1998. Compared to LCD with narrow viewing angle (40 °) and slow response time (30-60ms), the organic light emitting device has a viewing angle of 80 ° or more and a response speed of 0.01ms or less. The organic light emitting device has a low luminous efficiency (1.0 lm / W) and a large driving voltage (200 V), which requires a lot of power consumption (200 W, size 106.7 cm). Voltage is 2-5V and power consumption is less than 1W (size 26.4cm).

Application products include roll TVs, outdoor billboards, paper-based lighting, notebook computers, automobile dashboards, road signs, clock plates, laser diodes, and wall-mounted TVs.

Here, the characteristics of the organic light emitting device is a light emitting device, high brightness, high efficiency, low driving voltage (direct current drive, battery can be used), easy to change color (multicolor), large area, easy to bend, low price , High speed response (see Display, pp305-342 1999, EMDEC)

In general, when a cathode and an anode are formed at both ends of a film-like material of a thin film, when an electric field is applied, electrons and holes are injected and transferred into the film-like material, and when combined with each other, binding energy is emitted as light. , Electroluminescence). As materials having electroluminescent properties, both inorganic compounds and organic compounds can be used, and electroluminescent devices using inorganic materials have already been commercialized. However, inorganic electroluminescent devices have high power consumption and are difficult to obtain high luminance light, and are difficult to obtain various emission colors.

However, organic electroluminescent devices using organic compounds are driven by direct current voltages of several tens to several tens of volts, high brightness of several hundreds to thousands of cd / m2, and various light emission colors can be obtained according to molecular structure changes. It is the subject of interest in the field. Looking at the structure of the organic light emitting device briefly, the organic light emitting material having a semiconductor characteristic has a sandwich structure between the cathode and the anode in the form of a thin film. When a direct current field is applied to two electrodes of the device, electrons are injected into the organic light emitting material from the cathode, and holes are injected into the organic light emitting material from the anode. The electrons and the holes injected into the organic light emitting layer move through the organic light emitting layer under an electric field, combine with each other to form an exciton, and the electrons in the excited state of the exciton transition to the ground state and light in the visible region. It can be used as a display element.

Recently, as the size of a display increases, the demand for a display device having less space is increasing. In the case of personal information terminals including PCS (personal communication service), where demand is increasing steadily, liquid crystal displays are widely used, but organic light emitting diodes of self-luminescence attract attention because they have a narrow viewing angle and a slow response time. have. The organic light emitting display device has fast response speed and excellent brightness, and can realize low voltage driving due to thin film, and can realize all colors in the visible light range, which can be adapted to various tastes of modern people. In addition, the organic light emitting device can be formed on a flexible transparent substrate, such as plastic, as well as excellent characteristics such as wide viewing angle, high-speed response, high contrast (contrast). Such an organic light emitting display device can be used as a pixel of a graphic display or a surface light source, can be driven at a lower voltage than a plasma display panel or an inorganic light emitting display device, and consumes relatively little power. In addition, it is suitable for the next-generation flat panel display because it can easily realize three colors of green, red, and blue.

Therefore, as a research direction for the commercialization of the organic light emitting display device, improvement of the efficiency of the light emitting device and the implementation of full color display by implementing various colors are the main research subjects. The method for improving the efficiency of the organic light emitting device is possible by varying the structure of the electroluminescent device, that is, having not only a light emitting material between the cathode and the anode but also electron injection (electron transport) and hole injection (hole injection) characteristics A method of obtaining a highly efficient device by introducing a substance into the light emitting device at the same time to control the injection amount and mobility of electrons and holes.

As one of the research directions for commercialization, various colors of the organic light emitting diode can be realized by changing the structure of the light emitting material. The color emitted is of great importance for the manufacture of color displays. In order to obtain natural colors in color displays, red light, green light and blue light must be mixed in an appropriate ratio. In the case of full color displays such as cathode ray tube (CRT), liquid crystal display (LCD) and plasma display panel (PDP), fluorescent materials capable of emitting red light, green light and blue light are used as fine patterns. In the case of the organic light emitting device, a tricolor light emitting material must be developed to have a surface as a display. Among the three color light emitting materials known to be used for organic light emitting devices, green and blue materials have been developed with excellent brightness and efficiency, but in the case of red, the brightness and efficiency are significantly lower than those of green and blue, so full color organic light emitting devices It is not enough to manufacture.

Hereinafter, a structure and a method of forming an organic light emitting display device according to the prior art will be described with reference to the accompanying drawings.

1 is a structure of an organic light emitting display device. As shown in FIG. 1, the organic light emitting display device includes an anode 101, a hole injection layer 102, a hole transport layer 103, an emission layer 104, an electron transport layer 105, and an electron injection layer on the transparent substrate 100. 106 has a laminated structure in which a cathode 107 is sequentially formed.

ITO (Indium Tin Oxide, In ₂ O ₃ + SnO ₃ ) is mainly used as the anode 101 material formed on the transparent substrate 100 such as glass. The hole injection layer 102 is formed on the anode 101 and mainly copper phthalocyanine (Copper (II) (Phthalocyanine) is deposited to a thickness of 10 to 30 nm.The hole transport layer is formed on the hole injection layer 102. N, N-di (naphthalen-1-yl) -N, N'-diphenylbenzidine, which forms (103) and is mainly an organic dye, n, en-di (naphthalen-1-yl) ene, en'-diphenylbenzidine ) Is deposited at 30 to 60 nm.

Next, the organic light emitting layer 104 is formed on the hole transport layer 103. In this case, the organic light emitting layer 104 is formed in a state in which the light emitting material is doped with the light emitting material alone or the host material as necessary. Using green light as an example, the green light organic light emitting layer 104 may be formed of N-methylquinacridone and N-methylquinacridone in a host such as tris (8-hydroxyquinolate) aluminum (Alq3). It is formed by doping the same luminescent material (organic pigment), it is made of a thickness of about 30 ~ 60nm. In addition, the host can be used alone as a light emitting material without doping, Alq3 is mainly used for green light.

The electron transport layer 105 is formed on the organic light emitting layer 104, mainly Alq3 is deposited to a thickness of 20 ~ 50nm. In addition, the electron injection layer 106 is formed on the electron transport layer 105, and is vacuum deposited to a thickness of 30 to 50 nm mainly with an alkali metal derivative (Li ₂ O). Deposition of Al / Li onto the cathode 107 made of metal on the electron injection layer 106 completes the organic light emitting device.

In the case of blue light and red light, the organic light emitting layer is formed by using a unique material and doped with a light emitting material alone or a host material, and the device can be manufactured by the same method as for green light.

However, the organic light emitting device as described above has the following problems.

First, even though the organic light emitting device has a multilayer structure such as an anode, a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, an electron injection layer, and an anode, the luminous efficiency is low and thus insufficient for display.

Second, the performance of the materials of each layer of the organic light emitting device is insufficient.

Third, among the three color light emitting materials known for the organic light emitting device, red is significantly lower in brightness and efficiency than green and blue, and thus, it is insufficient to manufacture a full color organic light emitting device.

The present invention has been made to solve the above problems, and provides a red organic light emitting material having a hole transport characteristics, electron transport characteristics and red light emission characteristics at the same time, by using the red organic light emitting material as a light emitting layer, The purpose of the present invention is to provide a red organic light emitting display device having excellent efficiency, high brightness, and color purity unlike when using a light emitting material.

The red organic light emitting material and the electroluminescent device using the red organic light emitting material of the present invention for achieving the above object provides an organic light emitting material having both a hole transport characteristics, electron transport characteristics and red light emission characteristics under an electric field, By using the organic light emitting material also as a light emitting layer is characterized in that it provides a red organic electroluminescent device excellent in high efficiency, high brightness and color purity unlike when using a conventional light emitting material.

Hereinafter, a red organic light emitting material and an electroluminescent device using the red organic light emitting material according to the present invention will be described in detail with reference to the accompanying drawings.

First, the red organic light emitting material for an organic light emitting display device according to the present invention has a phenocazine group and an anthracene group having excellent electron transport ability, as shown in Chemical Formulas 1, 2 and 3, and pi (π)- It is characterized in that it is connected in conjugate form. In said Formula (1), (2) and (3), R <_1> is C1-C20 aliphatic hydrocarbon, R <_2> is hydrogen (H), and cyano group (CN) was introduce | transduced. Here, when R ₁ is not limited to an aliphatic hydrocarbon and is an aryl group, a heteroaryl group, or the like, the adhesion of the deposited film and the uniformity of the deposited film thickness after vacuum deposition are excellent. In addition, in the case of R ₂ , not only hydrogen (H) but also various kinds of substituents, as a result, light emission of not only the red region but also the green region can be confirmed. In particular, in the case of a compound in which a cyano (CN) group was introduced, it was confirmed that the color purity of red light was much better.

R ₁ and R ₂ in Formula 1 may be the same or different, hydrogen (H), aryl (aryl), heteroaryl (hetroaryl), halogen (halogen) group, 1 to 20 carbon atoms, saturated or unsaturated Selected from hydrocarbons.

In Formula ₂ R _1, R 2 may be the same or different and are hydrogen (H), aryl (aryl) group, a heteroaryl group (hetroaryl) group, a halogen (halogen) groups, the carbon number is 1-20, saturated or unsaturated Selected from hydrocarbons.

R ₁ and R ₂ in Formula 3 may be the same or different, hydrogen (H), aryl (aryl), heteroaryl (hetroaryl), halogen (halogen) group, 1 to 20 carbon atoms, saturated or unsaturated Selected from hydrocarbons.

Preparation of Formula 1, Formula 2 or Formula 3 of the present invention is synthesized by combining the Arbuzov reaction, Honor-Emmons reaction, Knoevenage reaction and the like.

First, the synthesis process of Formula 1 will be described.

Phenothiazine represented by the formula (4) and alkyl halide or aryl halide represented by the formula (5) are reacted in the presence of alkali to obtain the formula (6), and the formula (6) is phosphoryl chloride (phosphorusoxy chloride) and dimethyl formamide (dimethyl formamide) ) To obtain a compound as shown in Formula 7.

In Formula 5, R ₁ is selected from hydrogen (H), an aryl group, a heteroaryl group, a halogen group, a halogen group, a saturated or unsaturated hydrocarbon having 1 to 20 carbon atoms, and X is F, Cl , Br, I.

In Formula 6, R ₁ is selected from hydrogen (H), an aryl group, a heteroaryl group, a halogen group, a halogen group, and a saturated or unsaturated hydrocarbon having 1 to 20 carbon atoms.

In Formula 7, R ₁ is selected from hydrogen (H), an aryl group, a heteroaryl group, a halogen group, a halogen group, and a saturated or unsaturated hydrocarbon having 1 to 20 carbon atoms.

Here, in Formula 1, Formula 2 or Formula 3, when R ₁ is hydrogen (H), the reaction process of Formula 4 and Formula 5 is not necessary, and Formula 4 is directly replaced with phosphorusoxy chloride and dimethylformamide ( dimethyl formamide) to obtain a compound as shown in Formula 7.

In the preparation of Chemical Formula 6 by the reaction of Chemical Formula 4 and Chemical Formula 5, the reaction solvent is one selected from dimethyl sulfoxide, dimethyl formamide, and alcohols. , Preferably dimethyl sulfoxide.

The alkali used to obtain the formula (6) is at least one selected from sodium hydroxide, potassium hydroxide, sodium hydride, sodium methoxide, sodium ethoxide, preferably sodium hydroxide, sodium hydride. The highest yield was obtained when the compound represented by Chemical Formula 6 was reacted with 1.5-2 mole of alkali and alkyl halide or aryl halide compared to 1 mol of phenocyazine. 1,2-dichloroethane (1,2-dichloroethane) is suitable as a reaction solvent for reacting Chemical Formula 6 with phosphoryl chloride and dimethyl formamide to obtain Chemical Formula 7. Phosphoryl chloride and dimethyl formamide are liquid at room temperature and do not need to be used.

When preparing the compound represented by Formula 7 it is preferable to use 1 to 2 mole of dimethyl formamide and phosphoryl chloride (phosphoryl chloride) compared to 1 mole of the formula 6, the aldehyde group In addition, the preparation of Chemical Formula 2, which is further introduced, preferably uses 8 to 10 mole of dimethyl formamide and phosphoryl chloride compared to 1 mole of Chemical Formula 6.

The aldehyde of Formula 7 is thionyl chloride (SOCl ₂ ), tertiary butoxy chloride, en-bromosuccinimide in the presence of a substance generating radicals such as azobisisobutyronitrile React with compounds such as (N-bromosucciimide) to produce acyl halide compounds.

Such acyl halide compounds are easily reacted with aryl compounds (phenyl, naphthalene, biphenyl, terphenyl, anthracene, etc.), heteroaryl compounds (pyridine, quinoline, picoline, etc.), alkenes, etc. To a compound of formula (8).

R ₁ and R ₂ in Formula 8 may be the same or different, hydrogen (H), aryl (aryl), heteroaryl (hetroaryl), halogen (halogen) group, 1 to 20 carbon atoms, saturated or unsaturated Selected from hydrocarbons.

In order to react with the ketone group of the compound of Formula 8 to form a double bond in which a cyano group is introduced as in Formula 1, a compound having a cyano methyl group is required, and the preparation thereof may be prepared from Formula 9. The manufacturing process will be described in detail as follows. 267 ml of methyl isobutyl ketone, 133 ml of dioxane, 67 ml of distilled water, 50 g of potassium cyanide (97%), 0.4 g of cuprous cyanide and 0.4 g of cuprous cyanide were mixed and heated under reflux. Let's do it. 17 g of 9,10-bis (chloromethyl) anthracene (9,10-bis (chloromethyl) anthracene), a compound of Formula 9, was added dropwise to the reaction mixture over 2 hours, followed by heating to reflux for 8 hours. After heating for 8 hours at reflux for 10 hours, the solid product precipitates, and after recrystallization with dimethyl formamide, the compound of Formula 10 having a melting point of 336 ° C. can be obtained in high yield.

Formula 8 and Formula 10 may be reacted under an acid catalyst or an alkali catalyst to form a double bond into which a cyano group is introduced, thereby obtaining Formula 1 in high yield. The reaction process is as follows. The compound represented by the formula (8) and 9,10-anthracenediactronitrile (9,10-anthracenediactronitrile) represented by the formula (10) were mixed in the reactor in the same equivalent weight and then dissolved by adding tetrahydrofurane (tetrahydrofurane) The temperature is raised to 60 ℃. To this, tetrabutylammonium hydroxide solution was slowly added and stirred for 5 hours. After completion of the reaction, the solvent was removed with a rotary evaporator, washed with methanol and water, filtered, and vacuum dried (50 ° C.) to obtain Chemical Formula 1. When the electroluminescent device as shown in FIG. 2 is manufactured using the chemical formula 1 obtained by the above method, high luminance and high efficiency red light is obtained when a DC electric field is applied.

In addition, the synthesis process of Chemical Formulas 2 and 3 is as follows. First, the preparation of Chemical Formula 11 as a raw material required for the synthesis of Chemical Formulas 2 and 3 was performed using chloromethylanthracene (ClCH ₂ -anthracene) as a starting material.

It is the same as the conditions for preparing Formula 10.

In addition, in order to obtain the above Chemical Formula 2, the synthesis of Chemical Formula 12 having two ketone groups introduced therein should be made.

R ₁ and R ₂ in Formula 12 may be the same or different, hydrogen (H), aryl (aryl), heteroaryl (hetroaryl), halogen (halogen) group, 1 to 20 carbon atoms, saturated or unsaturated Selected from hydrocarbons.

First, a process of first synthesizing a substance into which two aldehyde groups are introduced in Chemical Formula 6 and then converting the introduced aldehyde group to a ketone group is required. Looking at the synthesis process of the compound in which two aldehyde groups are introduced in Formula 6, 8 to 10 mole of dimethyl formamide and phosphoryl chloride (phosphoryl chloride) compared to 1 mole of Formula 6, the aldehyde group 2 Synthesis of dog-introduced compound (N- (aryl-3,6-diformylphenothiazine)) is possible. The process of converting the introduced aldehyde group to a ketone group Dissolve (N- (aryl-3,6-diformylphenothiazine)) in a solvent and generate radicals such as azobisisobutyronitrile. material under the presence of thionyl chloride (SOCl _2), emitter eoseori butoxy chloride (tertiary butoxy chloride) or N - bromo succinimide acyl halide compound to react with the compounds, such as imide (N-bromosucciimide) (acyl chloride, acyl bromide Id, acyl fluoid), which are again aryl compounds (phenyl, naphthalene, biphenyl, terphenyl, anthracene, etc.), heteroaryl compounds (pyridine, quinoline, picoline, etc.) or It can be obtained by reacting with an alkene compound.

When Chemical Formula 11 and Chemical Formula 12 obtained by the above method are reacted under an acid catalyst or an alkali catalyst, Chemical Formula 2 may be synthesized. Detailed reaction conditions are the same as the preparation method of Chemical Formula 1 by the reaction of Chemical Formula 8 and Chemical Formula 10.

Next, the preparation of Chemical Formula 3 may be performed by reacting the chemical formula 8 and Chemical Formula 11 as raw materials under the same conditions as the synthesis of Chemical Formula 1 or Chemical Formula 2. As described above, the preparation of Chemical Formula 2 and Chemical Formula 3 can be easily achieved by appropriately applying the synthetic conditions of Chemical Formula 1.

Another feature of the present invention is to provide an organic electroluminescent device of high brightness and high efficiency using the organic light emitting material. Hereinafter, with reference to the accompanying drawings in detail as follows.

2 is a structure of the organic light emitting display device. As shown in FIG. 2, the organic light emitting display device includes an anode 201, a hole injection layer 202, a hole transport layer 203, an organic light emitting layer 204, an electron transport layer 205, and an electron injection on the transparent substrate 200. The layer 206 and the cathode 207 have a laminated structure formed sequentially.

First, the anode 201 is formed on the transparent substrate 200 by sputtering or the like. The material of the anode 201 is ITO (Indium Tin Oxide, In ₂ O ₃ + S _n O ₃ ) or IZO (Indium Zinc Oxide, In ₂ O ₃ + ZnO).

The hole injection layer 202 is formed on the anode 201. Copper phthalocyanine (Copper (II) Phthalocyanine) is used as a material of the hole injection layer 202.

In addition, N, N-di (naphthalen-1-yl) ene, N'-diphenylbenzidine (N, N'-di (naphthalen-1-) as the hole transport layer 203 on the hole injection layer 202. Triphenylamine or diphenylamine derivatives such as yl) N, N'-diphenylbenzidine) can be used.

The organic light emitting layer 204 is deposited on the hole transport layer 203. At this time, the organic light emitting layer 204 is formed in a state in which the light emitting material is doped to the light emitting material alone or the host material, if necessary, Formula 1, Formula 2 or Formula 3 of the present invention is a light emitting layer used as a dopant, It may be a single light emitting layer consisting of only the formula (2) or formula (3). That is, in the case of green light, the organic light emitting layer 204 is formed of a material such as Chemical Formula 1, Chemical Formula 2 or Chemical Formula 3 in a host such as tris (8-hydroxyquinolate) aluminum (Alq3). It is formed by doping and is made of a thickness of about 30 ~ 60nm.

Alq3 used as a host of the organic light emitting layer 204 has excellent electron transport characteristics, and thus may be used as the electron transport layer 205 on the organic light emitting layer 204. As another material that may be used as the electron transport layer 205, 2- (4-biphenyl) -5- (4-tert-butylphenyl) -1,3,4-oxadiazole (2- There are oxadiazole and oxatriazole derivatives, such as (4-biphenyl) -5- (4-tert-butylphenyl) -1,3,4-oxadiazole).

The electron injection layer 206 is deposited on the electron transport layer 205. Alkali metals (Cs, Rb, K, Na, Li) and alkali metal derivatives (Li ₂ O) may be used as materials of the electron injection layer 206, and are formed on the electron injection layer 206. As the cathode material, Ma / Ag, Al, Al / Li, Al / Nd, or the like is used.

In Formula 1, Formula 2, or Formula 3 used as the organic light emitting layer 204, the anthracene having a large electron accepting property and the phenocyazine having excellent electron donor properties are conjugated to each other, so that not only light emission characteristics but also hole transport characteristics And electron transport characteristics at the same time. In particular, the cyano groups of Formulas 1, 2 and 3 play a role of increasing the conjugated length of the compound because carbon and nitrogen are bonded by triple bonds. To improve. In addition, since the light emitting material itself has excellent hole transporting properties and electron transporting properties, a high luminance and high efficiency red light emission is obtained, which is superior to conventional red light emitting organic light emitting materials, and high purity red light is obtained by the presence of cyano groups.

That is, when electrons and holes that are moved to the electron transport layer 205 and the hole transport layer 202 are injected into the organic light emitting layer 204, the organic light emitting layer itself has excellent hole and electron transport characteristics, Injection into the 204 is much easier than the conventional light emitting material, so that the possibility of electrons and holes to meet and form excitons is further increased, thereby enabling high brightness and high efficiency. In addition, the presence of cyano groups serves to shift the light emission wavelength to a long wavelength, thereby obtaining pure red light.

In this case, it is possible that Formula 1, Formula 2 and Formula 3 exhibit red light because an exciplex (excited charge transfer complex) is formed by the interaction of an electron donor phenocazine and an anthracene electron acceptor. That is, the band gap energy of Formula 1, Formula 2, or Formula 3 in which the exciplexes are formed between the molecules is smaller than that in the case of not forming the exciplex. Here, the conjugate length increases due to the presence of cyano groups, which results in shifting the luminescent wavelength to the long wavelength region, whereby red having excellent color purity is obtained.

Formula 1, Formula 2 and Formula 3 of the present invention is composed of a material having an electron donor and an electron acceptor characteristic is possible to emit red light by the exciplex formation and the electron donor phenocyazine group has a hole transport characteristics In addition, the electron acceptor anthracene provides electron transport characteristics, thereby making it possible to emit red light of high brightness and high efficiency in the organic light emitting device. In addition, the presence of the cyano group serves to increase the conjugate length and eventually to shift the light emission wavelength to long wavelength. That is, when hydrogen is bonded to the cyano group in Chemical Formula 1, the maximum wavelength was 612 nm, but the Chemical Formula 1 substituted with the cyano group showed the maximum wavelength of 645 nm.

In addition, when the organic light emitting diode is manufactured by using Chemical Formula 1, Chemical Formula 2, and Chemical Formula 3, a pure red emission spectrum (645 nm) can be obtained when DC power is applied, and a high efficiency of 6 to 8 lm / W is obtained. , High luminance of 1000 to 1800 cd / m 2 was obtained.

3 is a structure of an organic light emitting display device which does not separately form an electron transport layer and a hole transport layer because the light emitting material itself has excellent electron transport characteristics and hole transport characteristics. The structure (anode 301 / hole injection layer 302 / organic light emitting layer 304 / electron injection layer 306 / cathode 307) of FIG. 3 also has excellent brightness and efficiency. At this time, the organic electroluminescent device of FIG. 3 has a structure except for the hole transport layer and the electron transport layer in the organic electroluminescent device of FIG.

In addition, as shown in FIG. 4, even when the organic electroluminescent device having a single layer structure (anode 401 / organic light emitting layer 404 / cathode 407) is formed, high luminance and high efficiency can be obtained. In this case, the formation of the organic light emitting diode of FIG. 4 is the same as that of FIG.

Next, in the first embodiment, the organic light emitting diode of FIG. 2 was manufactured using the synthesized Chemical Formula 1. First, copper (II) phthalocyanine is vacuum-deposited on the ultrasonically cleaned ITO glass to form a hole injection layer 202 having a thickness of 30 nm. N, N'-di (naphthalen-1-yl) -N, N'-diphenylbenzidine (N, N-di (naphthalen-1-yl) as the hole transport layer 203 on the hole injection layer 202. N, N'-diphenylbenzidine) is deposited to a thickness of 50 nm. The organic light emitting layer 204 is deposited on the hole transport layer 203 to a thickness of 30 nm. In addition, Alq3 is deposited to a thickness of 40 nm as the electron transport layer 205 on the organic light emitting layer 204, and Li ₂ O as an electron injection layer 206 is deposited on the electron transport layer 205 to a thickness of 25 nm. Finally, Mg and Ag, which are cathodes 207, are deposited on the electron injection layer 206 to a thickness of 100 nm. When the anode is connected to ITO and the cathode is connected to the Mg and Ag layers, a red spectrum having a maximum emission wavelength of 645 nm is obtained. In this case, the luminance is 1800 cd / m 2 and the efficiency is 8.1 lm / W.

In the second embodiment, the organic electroluminescent device such as ITO glass / hole injection layer / light emitting layer / electron injection layer / Mg, Ag is omitted by the same method as in the first embodiment, but omitting the formation of the electron transport layer and the hole transport layer. It was prepared, and shows a luminance of 1400 cd / m 2 and an efficiency of 7.2 lm / W when DC power is applied. In this case, the maximum emission wavelength of the spectrum measured by the photoresearch company PR-650 was 645 nm.

In the third embodiment, the organic light emitting diode was manufactured under the same conditions as in the first embodiment using the formula (2) or the formula (3) instead of the formula (1) used as the light emitting layer in the first embodiment. The anode power was connected to ITO, the cathode power was applied to the Mg and Ag layers, and the emitted light was measured by Photoresearch's PR-650. As a result, the maximum light emission wavelength was 550 ~ 690nm according to R ₁ and R ₂ types The brightness was 1100 ~ 1800cd / ㎡, the efficiency was in the range of 6.5 ~ 9.3 lm / W.

Next, the fourth embodiment was formed using the formula (1) as a dopant and Alq3 as a host to form a light emitting layer, and other manufacturing conditions were the same as the first embodiment to manufacture and evaluate the organic light emitting device. As a result, the maximum light emission wavelength was 642 nm, where luminance was 1900 cd / m 2 and efficiency was 8.9 lm / W.

The red material for an organic light emitting display device and the electroluminescent device using the same according to the present invention have the following effects.                     

First, Chemical Formula 1, Chemical Formula 2 or Chemical Formula 3 of the present invention is an phenocazine group having a function of hole transport (electron system) and an anthracene group having a function of electron transport (electron acceptor) with red light emission by exciplex formation. And because it has a cyano group at the same time, the organic light emitting device manufactured using the same can provide a high luminance of more than 1000cd / ㎡ and a high efficiency electroluminescent device of more than 7 lm / W.

Second, the introduction of cyano groups serves to shift the light emission wavelength to a long wavelength, from which a high purity red light emitting device can be obtained.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the spirit of the present invention.

Therefore, the technical scope of the present invention should not be limited to the contents described in the embodiments, but should be defined by the claims.

Claims (6)

Red organic light emitting material represented by the following formula (1) characterized in that the organic light emitting device generates visible light. Formula 1

      (In the above meal, R ₁ and R ₂ are selected from hydrogen (H), aryl group, heteroaryl group, halogen group, saturated or unsaturated hydrocarbon having 1 to 20 carbon atoms.) Red organic light emitting material represented by the following formula (2) characterized in that the organic light emitting device generates visible light. Formula 2

(In the above meal, R ₁ and R ₂ are selected from hydrogen (H), aryl group, heteroaryl group, halogen group, saturated or unsaturated hydrocarbon having 1 to 20 carbon atoms.) A red organic light emitting material represented by the following Chemical Formula 3, wherein the organic light emitting device generates visible light. Formula 3

      (In the above meal, R ₁ and R ₂ are selected from hydrogen (H), aryl group, heteroaryl group, halogen group, saturated or unsaturated hydrocarbon having 1 to 20 carbon atoms.) An organic electroluminescent device in which an anode, an organic material layer, and a cathode are sequentially stacked on a substrate, wherein the organic material layer comprises a light emitting layer containing Formula 1, Formula 2, or Formula 3 below. Formula 1

(In the above meal, R ₁ and R ₂ are selected from hydrogen (H), aryl group, heteroaryl group, halogen group, saturated or unsaturated hydrocarbon having 1 to 20 carbon atoms.) Formula 2

(In the above meal, R ₁ and R ₂ are selected from hydrogen (H), aryl group, heteroaryl group, halogen group, saturated or unsaturated hydrocarbon having 1 to 20 carbon atoms.) Formula 3

(In the above meal, R ₁ and R ₂ are selected from hydrogen (H), aryl group, heteroaryl group, halogen group, saturated or unsaturated hydrocarbon having 1 to 20 carbon atoms.) The organic light emitting device of claim 4, wherein the organic material layer comprises an electron injection layer, an organic light emitting layer, and a hole injection layer. The organic light emitting device of claim 4, wherein the organic material layer comprises an electron injection layer, an electron transport layer, an organic light emitting layer, a hole transport layer, and a hole injection layer.

Images