KR20100072644A - Organic light emitting diode device - Google Patents

Abstract

PURPOSE: An organic electric field radiating element is provided to improve a brightness characteristic by forming a second radiating layer including green phosphorescence, a red dopant and a first radiating layer including the phosphorescence and a fluorescence blue dopant. CONSTITUTION: A first stack(130) is located on an anode electrode(120). The first stack includes a radiating layer. The first radiating layer includes a phosphorescence blue dopant and a fluorescence blue dopant. A charge generating layer(140) is located on the first stack. A second stack(150) is located on the charge generating layer. The second stack includes a second radiating layer. The second radiating layer includes a phosphorescence green dopant and a phosphorescence red dopant. A cathode electrode(160) is located on the second stack.

Description

Organic Light Emitting Diode Device

The present invention relates to an organic light emitting display device, and more particularly, to an organic light emitting display device capable of improving color stability and high efficiency.

Recently, the importance of flat panel displays (FPDs) has increased with the development of multimedia. In response to this, a variety of liquid crystal displays (LCDs), plasma display panels (PDPs), field emission displays (FEDs), organic light emitting devices (Organic Light Emitting Devices), etc. Flat panel displays have been put into practical use.

In particular, the organic light emitting device has a high response time with a response speed of 1 ms or less, low power consumption, and self-luminous light. In addition, there is no problem in viewing angle, which is advantageous as a moving image display medium regardless of the size of the device. In addition, low-temperature manufacturing is possible, and the manufacturing process is simple based on the existing semiconductor process technology has attracted attention as a next-generation flat panel display device in the future.

The organic light emitting device includes a light emitting layer between the anode electrode and the cathode electrode, so that holes supplied from the anode electrode and electrons received from the cathode electrode combine in the light emitting layer to form an exciton, a hole-electron pair, and then the exciton is bottomed. The light emitted by the energy generated when returning to the state.

Such organic light emitting diodes are being developed in various structures, among which white organic light emitting diodes are generally developed in a structure in which a red light emitting layer, a green light emitting layer, and a blue light emitting layer are stacked.

However, the white organic light emitting diode having a laminated structure has problems such as low lifespan of the blue light emitting layer, low color stability, and relatively high driving voltage. There is a problem with this falling.

Accordingly, the present invention provides an organic light emitting device capable of improving color stability and realizing high efficiency.

In order to achieve the above object, an organic light emitting display device according to an embodiment of the present invention is an anode electrode, the anode is located on the anode, the first light emitting layer comprising a phosphorescent blue dopant and a fluorescent blue dopant in one host And a second stack including a first stack including a first stack, a charge generation layer positioned on the first stack, and a second light emitting layer disposed on the charge generation layer and including green and red dopants in one host. It may include a cathode electrode located on the two stacks.

The first stack may include a first hole injection layer and a first hole transport layer formed between the anode electrode and the first emission layer, and a first electron transport layer and a first electron injection layer formed between the first emission layer and the charge generation layer. It may further include.

The second stack may include a second hole injection layer and a second hole transport layer formed between the charge generation layer and the second emission layer, and a second electron transport layer and a second electron injection layer formed between the second emission layer and the cathode electrode. It may further include.

An exciton blocking layer may be further included between the first hole transport layer and the first light emitting layer or between the second hole transport layer and the second light emitting layer.

The second emission layer may include a phosphorescent or fluorescent green dopant and a phosphorescent or fluorescent red dopant in one host.

In addition, an organic light emitting display device according to an embodiment of the present invention includes an anode electrode, a first stack disposed on the anode electrode, and having a first light emitting layer including green and red dopants in one host, the first stack A second stack having a charge generation layer positioned on the stack and a second light emitting layer positioned on the charge generation layer and having a second light emitting layer including a phosphorescent blue dopant and a fluorescent blue dopant in one host; It may include a cathode electrode.

The first stack may include a first hole injection layer and a first hole transport layer formed between the anode electrode and the first emission layer, and a first electron transport layer and a first electron injection layer formed between the first emission layer and the charge generation layer. It may further include.

The second stack may include a second hole injection layer and a second hole transport layer formed between the charge generation layer and the second emission layer, and a second electron transport layer and a second electron injection layer formed between the second emission layer and the cathode electrode. It may further include.

An exciton blocking layer may be further included between the first hole transport layer and the first light emitting layer or between the second hole transport layer and the second light emitting layer.

The second emission layer may include a phosphorescent or fluorescent green dopant and a phosphorescent or fluorescent red dopant in one host.

The organic light emitting display device according to an embodiment of the present invention has an advantage of improving color stability and high efficiency and further reducing power consumption of the organic light emitting display device.

Hereinafter, various embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a view showing an organic light emitting display device according to a first embodiment of the present invention.

Referring to FIG. 1, the organic light emitting display device 100 according to the first exemplary embodiment of the present invention may be a white organic light emitting display device of white light including light of red, green, and blue wavelengths.

The organic light emitting display device 100 according to the first exemplary embodiment of the present invention is positioned on the anode electrode 120 and the anode electrode 120 on the substrate 110, and has a phosphorescent blue dopant and a fluorescent blue on one host. A first stack 130 having a first emission layer 133 including a dopant, a charge generation layer 140 positioned on the first stack 130, and a charge generation layer 140 positioned on the charge generation layer 140; It may include a second stack 150 having a second light emitting layer 154 including a green and a red dopant in one host and a cathode electrode 160 positioned on the second stack 150.

The substrate 110 may be made of transparent glass, plastic, or a conductive material.

The anode 120 may be a transparent electrode or a reflective electrode. When the anode electrode 120 is a transparent electrode, the anode electrode 120 may be any one of indium tin oxide (ITO), indium zinc oxide (IZO), or zinc oxide (ZnO). In addition, when the anode electrode 120 is a reflective electrode, the anode electrode 120 is made of any one of aluminum (Al), silver (Ag), or nickel (Ni) under a layer made of any one of ITO, IZO, or ZnO. The reflective layer may further include a reflective layer, and in addition, the reflective layer may be included between two layers made of any one of ITO, IZO, or ZnO.

The first stack 130 may include a first emission layer 133 including a phosphorescent blue dopant and a fluorescent blue dopant in one host. Since the first stack 130 emits only blue light, including only the blue light emitting layer as the first light emitting layer 133, the color stability of blue can be improved.

The first light emitting layer 133 is a light emitting layer emitting blue light, and a phosphorescent blue dopant and a fluorescent blue dopant may be mixed in one host having a wide band gap.

For example, the first emission layer 133 may be formed of AND (9,10-di (2-naphthyl) anthracene) or DPVBi (4,4'-bis (2,2-diphenylethen-1-yl) as shown below. fluoride blue dopants such as 1,6-Bis (diphenylamine) pyrene and TBPe (tetrakis (t-butyl) perylene) and Ir (pFCNp) ₃ (tri (2- (2,4-) Phosphorescent blue dopants such as difluoro-3-cyanophenylpyridine) iridium (III)) may be mixed.

The first stack 130 may include a first hole injection layer 131 and a first hole transport layer 132 and the first light emitting layer 133 formed between the anode electrode 120 and the first light emitting layer 133. The electronic device may further include a first electron transport layer 134 and a first electron injection layer 135 formed between the charge generation layer 140.

The first hole injection layer (HIL) 131 may play a role of smoothly injecting holes from the anode 120 to the first emission layer 133, and may include cupper phthalocyanine (CuPc), PEDOT (poly (3,4) -ethylenedioxythiophene), PANI (polyaniline) and NPD (N, N-dinaphthyl-N, N'-diphenyl benzidine) may be made of any one or more selected from the group consisting of, but not limited to.

The first hole injection layer 131 may be formed by an evaporation method or a spin coating method, and may have a thickness of 5 to 150 nm.

The first hole transport layer (HTL) 132 serves to facilitate the transport of holes, NPD (N, N-dinaphthyl-N, N'-diphenyl benzidine), TPD (N, N ' -bis- (3-methylphenyl) -N, N'-bis- (phenyl) -benzidine), s-TAD and MTDATA (4,4 ', 4 "-Tris (N-3-methylphenyl-N-phenyl-amino ) -triphenylamine) may be composed of any one or more selected from the group consisting of, but is not limited thereto.

The first hole transport layer 132 may be formed by evaporation or spin coating, and may have a thickness of 5 to 150 nm.

The first electron transport layer (ETL) 134 serves to facilitate the transport of electrons, and includes Alq3 (tris (8-hydroxyquinolino) aluminum), PBD, TAZ, spiro-PBD, BAlq and SAlq. It may be made of one or more selected from the group consisting of, but is not limited thereto.

The first electron transport layer 134 may be formed by an evaporation method or a spin coating method, and may have a thickness of 1 to 50 nm.

The first electron injection layer (EIL) 135 serves to facilitate the injection of electrons, Alq3 (tris (8-hydroxyquinolino) aluminum), PBD, TAZ, spiro-PBD, BAlq or SAlq May be used, but is not limited thereto.

The first electron injection layer 135 may further include a metal compound including an alkali metal or an alkaline earth metal.

In addition, the first electron injection layer 135 may be formed by evaporation or spin coating, and may have a thickness of 1 to 50 nm.

The charge generation layer (CGL) 140 may be formed of a single layer or a double layer. First, in the case of a single layer, a metal oxide may be used, for example, V ₂ O ₅ or WO ₃ may be used. In addition, when the charge generation layer 140 is formed of a double layer, a structure in which metal oxides / metals are sequentially stacked may be used. In this case, V ₂ O ₅ or WO ₃ may be used as the metal oxide, and all metals may be used as the metal, but Al or Ag may be preferably used.

The charge generation layer 140 may be formed by one method selected from the group consisting of spin coating, dip coating, vacuum deposition, and inkjet printing, and may have a thickness of 30 to 50 μs.

In this case, when the power is applied to the anode electrode 120 and the cathode electrode 160, the charge generation layer 140 generates charges, ie, electrons and holes, in the charge generation layer 140 by the power source. It serves to provide electrons and holes to the adjacent first light emitting layer 133 and the second light emitting layer 154, respectively. Therefore, the distribution of the charge is uniformly made in each light emitting layer to prevent the disadvantage of emitting light in one color.

The second stack 150 may include a second emission layer 154 including green and red dopants in one host.

For example, the second emission layer 154 may be formed of CBP (4,4'-N, N'-dicarbazolebiphenyl) or Balq (Bis (2-methyl-8-quinlinolato-N1, O8)-( Phosphorescent green dopant of Ir (ppy) ₃ and Ir (Mnpy) ₃ , Btp2Ir (acac) (bis (2O-benzo [4,5) in any one of 1,1'-Biphenyl-4-olato) aluminium) A phosphorescent red dopant selected from -a] thienyl) pyridinato-N, C3O) iridium (zcetylactonate) or Btp2Ir (acac) (iridium (III) bis (1-phenylisoquinolyl) -N, C2 ') acetylacetonate may be mixed. have.

Alternatively, the second light emitting layer 154 may be a mixture of a fluorescent green dopant of tris (8-hydroxyquinolino) aluminum (Alq3) and a fluorescent red dopant of PBD: Eu (DBM) ₃ (Phen) or perylene in one host. It is not limited to this.

The second stack 150 may include a second hole injection layer 151 and a second hole transport layer 152 and the second light emitting layer 154 formed between the charge generation layer 140 and the second light emitting layer 154. And a second electron transport layer 155 and a second electron injection layer 156 formed between the cathode electrode 160 and the cathode electrode 160.

The second hole injection layer 151, the second hole transport layer 152, the second electron transport layer 155, and the second electron injection layer 156 are the first hole injection layer 131 and the first hole transport layer described above. 132, the same as the first electron transport layer 134 and the first electron injection layer 135, the description thereof will be omitted.

An exciton blocking layer 153 may be further included between the second hole transport layer 152 and the second emission layer 154.

The exciton blocking layer (EBL) 153 suppresses diffusion of the exciton generated in the second emission layer 154 into the second hole transport layer 152 during the driving of the organic light emitting diode. By, it may be made of TCTA (4,4 ', 4 "-tris (N-carbazolyl) -triphenylamine), Balq, BCP, CF-X, TAZ or spiro-TAZ and the like.

The cathode electrode 160 may be made of aluminum (Al), magnesium (Mg), silver (Ag), or an alloy thereof having a low work function. Here, the cathode electrode 160 may be formed to be thin enough to transmit light in the case of top emission, and may be formed thick so that the light is reflected in case of the bottom emission.

An organic light emitting display device according to an embodiment of the present invention uses light emission through fluorescence and phosphorescence. Phosphorescence refers to the emission of organic molecules from the triplet excited state. In contrast, fluorescence means emission from a singlet excited state of organic molecules. Thus, the luminescence of the organic light emitting device shows fluorescence emission or phosphorescence emission.

Phosphorescence is due to the recombination of holes and electrons, so that all excitons formed in either a singlet or triplet excited state can participate in luminescence. This is because the lowest singlet excited state of the organic molecule is in a slightly higher energy state than the lowest triplet excited state. For example, in phosphorescent organometallic compounds, the lowest singlet excited state is the lowest triplet excited state where phosphorescence is produced.

It may collapse quickly.

In comparison, only about 25% of excitons in fluorescent elements can produce fluorescent luminescence resulting from a singlet excited state. In a fluorescent device, the remaining excitons produced in the lowest triplet excited state cannot be converted to the higher energy singlet excited states in which fluorescence is generated.

2 illustrates an energy transfer mechanism of the first light emitting layer of the organic light emitting diode, and FIG. 3 is a diagram illustrating a band diagram of the organic light emitting diode.

The energy transfer mechanism and band diagram of the organic light emitting display device as shown in FIG. 1 will be described with reference to FIGS. 2 and 3 based on the above-described light emission principle of fluorescence and phosphorescence.

Referring to FIG. 2, a fluorescent blue dopant and a phosphorescent blue dopant are mixed in one host in the first emission layer 133 of the first stack 130.

Phosphorescent blue dopants receive most of the singlet excitons and triplet exciter states from the host. The singlet exciter state in phosphorescent blue is brought down to triplet exciter state by ISC, and the triplet exciter state of phosphorescent blue dopant is theoretically close to 75%, which is the triplet exciter state of fluorescent blue dopant Energy can be transferred in the state to achieve internal quantum efficiency close to 100%. However, energy loss may occur due to the path (indicated by X) generated during the energy transfer process.

Referring to FIG. 3, the blue light is emitted from the first light emitting layer 133 by the energy transfer mechanism as described above, and the singlet exciter state and the triplet exciter state are phosphorescent green from the host in the second light emitting layer 154. The dopant and the phosphorescent red dopant are electrolyzed to emit green and red light, which finally emits white light.

Therefore, the organic light emitting display device according to an embodiment of the present invention can implement a white organic light emitting device of white color.

4 is a diagram illustrating an organic light emitting display device 200 according to a second embodiment of the present invention.

Referring to FIG. 4, the organic light emitting display device 200 according to the second embodiment of the present invention is positioned on the anode electrode 220 and the anode electrode 220 on the substrate 210, and located on one host. On the first stack 230 having a first light emitting layer 233 including green and red dopants, the charge generation layer 240 positioned on the first stack 230 and on the charge generation layer 240 A second stack 250 having a second light emitting layer 254 including a phosphorescent blue dopant and a fluorescent blue dopant in one host, and a cathode electrode 260 positioned on the second stack 250. It may include.

The organic light emitting device according to the second embodiment of the present invention has a structure in which the positions of the first light emitting layer and the second light emitting layer are interchanged in the organic light emitting device according to the first embodiment of the present invention described above. Therefore, description overlapping with the first embodiment will be omitted.

The first stack 230 includes a first hole injection layer 231 and a first hole transport layer 232 and the first light emitting layer 233 formed between the anode electrode 220 and the first light emitting layer 233. And a first electron transport layer 234 and a first electron injection layer 235 formed between the charge generation layer 240.

The second stack 250 may include a second hole injection layer 251 and a second hole transport layer 252 and the second light emitting layer formed between the charge generation layer 240 and the second light emitting layer 254. A second electron transport layer 255 and the second electron injection layer 256 formed between the 254 and the cathode electrode 260 may be further included.

An exciton blocking layer 254 may be further included between the first hole transport layer 232 and the first emission layer 233 or between the second hole transport layer 252 and the second emission layer 254.

The second emission layer 254 may include a phosphorescent or fluorescent green dopant and a phosphorescent or fluorescent red dopant in one host.

As described above, the organic light emitting diode according to the second embodiment of the present invention may implement a white white organic light emitting diode by emitting red and green light in the first light emitting layer and blue light in the second light emitting layer.

5 illustrates an organic light emitting display device having a bottom emission structure according to embodiments of the present invention.

Referring to FIG. 5, a thin film transistor TFT is positioned on a transparent substrate SUBS, and a pixel electrode PIX is connected to the thin film transistor TFT. The pixel electrode PIX is connected to the drain electrode D of the thin film transistor TFT and is connected to the anode electrode of the organic light emitting diode WOLE shown in FIG. 1. In FIG. 5, reference numeral “GI” denotes a gate metal pattern including a gate electrode G of the thin film transistor TFT and a gate line connected thereto, and source and drain electrodes S and D of the thin film transistor TFT and a data line. A gate insulating film for insulating a source / drain metal pattern including a. "PAS" is a passivation layer for protecting the thin film transistor TFT, in which a contact hole for contacting the pixel electrode PIX with the drain electrode D of the thin film transistor TFT is formed. . "BNK" is a structure for partitioning a red pixel, a green pixel, and a blue light emitting cell.

"ENCAP" is an encapsulation member that is adhered to the transparent substrate SUBS with a sealant including a getter. The organic light emitting diode (WOLED) has a two-layer stacked structure as shown in FIG. 1, and the light emitted by the light emission of the organic light emitting diode (WOLED) is a passivation layer (PAS), a gate insulating layer (GI), and an anode electrode. (ANO) and transparent substrate (SUBS). A red color filter, a green color filter, and a blue color filter may be formed between the transparent substrate SUBS and the organic light emitting diode WOLED to realize color.

Hereinafter, an experimental example according to an embodiment of the present invention is disclosed. However, the experimental examples disclosed below are only examples of the present invention, and the present invention is not limited to the following experimental examples.

Experimental Example 1

The light emitting area of the ITO glass was patterned to have a size of 2 mm x 2 mm and then washed. After mounting the substrate in the vacuum chamber, the base pressure was 1 × 10 ⁻⁶ torr, and the first hole injection layer DNTPD was deposited to a thickness of 600 kPa on the anode electrode ITO, and the first hole transport layer NPD was 400 kPa. It was formed into a thickness. Then, a 300 Å first light emitting layer was formed by co-depositing 1,6-Bis (diphenylamine) pyrene, which is a phosphorescent blue dopant, on the host ADN (9,10-di (2-naphthyl) anthracene). At this time, the doping concentration of the dopant was 5wt%. Subsequently, Alq ₃ , which is the first electron transport layer, was formed to have a thickness of 300 GPa, LiF, which was the first electron injection layer, was formed to have a thickness of 5 GPa, and Al, the cathode electrode, was formed to have a thickness of 1000 GPa to fabricate an organic light emitting display device. .

Experimental Example 2

An organic light emitting diode was manufactured under the same condition as Experimental Example 1, except that the first emission layer was formed using Ir (pFCNp) _3, which is a blue fluorescent dopant.

Experimental Example 3

1,6-Bis (diphenylamine) pyrene, a phosphorescent blue dopant, and Ir (pFCNp) ₃ , a fluorescent blue dopant, were mixed at a doping concentration of 10 wt% for a phosphorescent blue dopant and 1 wt% for a fluorescent blue dopant to form a first emission layer. Except, an organic light emitting display device was manufactured under the same condition as Experimental Example 1.

Experimental Example 4

An organic light emitting display device was manufactured under the same condition as Experimental Example 3, except that a TCTA, which was an exciton blocking layer, was formed between the first hole transport layer and the first light emitting layer to a thickness of 200 GPa.

Experimental Example 5

1,6-Bis (diphenylamine) pyrene, a phosphorescent blue dopant, and Ir (pFCNp) ₃ , a fluorescent blue dopant, were mixed at a doping concentration of 10 wt% for a phosphorescent blue dopant and 0.5 wt% for a fluorescent blue dopant to form a first emission layer. Except that, an organic light emitting display device was manufactured under the same condition as Experimental Example 1.

Experimental Example 6

TBPe, which is a phosphorescent blue dopant, and Ir (pFCNp) ₃ , which is a fluorescent blue dopant, were mixed at a doping concentration of 10 wt% of a phosphorescent blue dopant and 0.5 wt% of a fluorescent blue dopant to form a first light emitting layer. An organic light emitting diode was manufactured under the conditions.

The driving voltage, luminous efficiency, quantum efficiency, luminance and color coordinates of the organic light emitting diodes manufactured according to Experimental Examples 1 to 6 are shown in Table 1 below, and the emission spectra are shown in FIG. 6.

Driving voltage
(V) Luminous efficiency Quantum efficiency
(%) Luminance
(Cd / ㎡) Color coordinates Cd / A lm / W CIE_x CIE_y Experimental Example 1 4.8 8.7 5.6 7.2 867 0.134 0.189 Experimental Example 2 7.0 14.4 6.5 8.1 1442 0.155 0.348 Experimental Example 3 3.7 15.2 12.9 12.6 1520 0.131 0.243 Experimental Example 4 4.0 18.7 14.7 15.5 1870 0.131 0.264 Experimental Example 5 3.8 21.5 17.7 17.8 2150 0.132 0.287 Experimental Example 6 3.8 6.3 5.2 5.2 630 0.132 0.263

Referring to Tables 1 and 6, Experimental Examples 3 to 5, in which phosphorescent and fluorescent blue dopants were mixed, showed driving voltage, luminous efficiency, quantum efficiency, luminance, and color coordinate characteristics than Experimental Examples 1 and 2 using phosphorescent or fluorescent blue dopants. It turns out that this is remarkably excellent. On the other hand, in the case of different phosphorescent blue dopant in Experimental Example 6 it can be seen that all the properties are significantly lower due to inefficient energy transfer process.

And, as shown in Experimental Examples 3 and 4, the driving voltage is increased by about 0.3V with the presence of the exciton blocking layer, but it can be seen that the luminous efficiency, quantum efficiency and luminance characteristics are improved.

Based on this, the phosphorescent blue dopant and the fluorescent blue dopant of the first emission layer are set, and the following experiment is started.

Experimental Example 7

The light emitting area of the ITO glass was patterned to have a size of 2 mm x 2 mm and then washed. After mounting the substrate in the vacuum chamber, the base pressure was 1 × 10 ⁻⁶ torr, and the first hole injection layer DNTPD was deposited to a thickness of 600 kPa on the anode electrode ITO, and the first hole transport layer NPD was 400 kPa. It was formed into a thickness. A 300 (second light emitting layer was formed by co-depositing Ir (ppy) ₃ , which is a phosphorescent green dopant, and Ir (mnapy) ₃ , which is a phosphorescent red dopant, on the host CBP. At this time, the doping concentration of the dopant was 5wt%, respectively. Subsequently, Alq ₃ , which is the first electron transport layer, was formed to have a thickness of 300 GPa, LiF, which was the first electron injection layer, was formed to have a thickness of 5 GPa, and Al, the cathode electrode, was formed to have a thickness of 1000 GPa to fabricate an organic light emitting display device. .

Experimental Example 8

The light emitting area of the ITO glass was patterned to have a size of 2 mm x 2 mm and then washed. After mounting the substrate in the vacuum chamber, the base pressure was 1 × 10 ⁻⁶ torr, and the first hole injection layer DNTPD was deposited to a thickness of 600 kPa on the anode electrode ITO, and the first hole transport layer NPD was 400 kPa. It was formed into a thickness. Then, 300 제 of the first light emitting layer was formed by co-depositing Ir (pFCNp) ₃ as a fluorescent blue dopant on ADN (9,10-di (2-naphthyl) anthracene) which is a host. At this time, the doping concentration of the dopant was 5% of the fluorescent blue dopant. Subsequently, Alq ₃ , which is the first electron transport layer, was formed into a film having a thickness of 300 GPa, LiF which was the first electron injection layer was formed into a film having a thickness of 5 GPa, and WO ₃ , which was a charge generation layer, was formed into a film of 30 GPa. Next, DNTPD, the second hole injection layer, is deposited to a thickness of 600 kPa, NPD, the second hole transport layer, is deposited to a thickness of 400 kPa, TCTA, the exciton blocking layer, is deposited to a thickness of 200 kPa, and phosphorescent green on the host CBP. A 300 발광 second light emitting layer was formed by co-depositing Ir (ppy) ₃ as a dopant and Ir (mnapy) ₃ as a phosphorescent red dopant. At this time, the doping concentration of the dopant was 2wt%. Subsequently, Alq ₃ , which is the second electron transport layer, was formed to have a thickness of 300 kW, LiF, which was the second electron injection layer, was formed to have a thickness of 5 kW, and Al, which was a cathode electrode, was formed to have a thickness of 1000 kW, to fabricate an organic light emitting device. .

Experimental Example 9

1,6-Bis (diphenylamine) pyrene, a phosphorescent blue dopant, and Ir (pFCNp) ₃ , a fluorescent blue dopant, were mixed at a doping concentration of 10 wt% for a phosphorescent blue dopant and 0.5 wt% for a fluorescent blue dopant to form a first emission layer. Except that, an organic light emitting display device was manufactured under the same condition as Experimental Example 8.

The driving voltage, luminous efficiency, quantum efficiency, luminance, and color coordinates of the organic light emitting diodes manufactured according to Experimental Examples 7 to 9 are shown in Table 2 below, and the emission spectra are shown in FIG. 7.

Driving voltage
(V) Luminous efficiency Quantum efficiency
(%) Luminance
(Cd / ㎡) Color coordinates Cd / A lm / W CIE_x CIE_y Experimental Example 7 3.4 45.5 41.8 18.4 4550 0.449 0.529 Experimental Example 8 7.0 47.8 21.4 24.6 4776 0.352 0.375 Experimental Example 9 7.2 56.4 24.6 29.0 5640 0.333 0.399

Referring to Table 2 and FIG. 7, Experimental Example 9 having a first light emitting layer in which phosphorescent and fluorescent blue dopants are mixed and a second light emitting layer incorporating phosphorescent green and red dopants are compared to other driving examples 7 and 8. It can be seen that the luminous efficiency, quantum efficiency and luminance characteristics are remarkably excellent.

In addition, Experimental Example 8 having a first light emitting layer including a fluorescent blue dopant and a second light emitting layer in which phosphorescent green and red dopants were mixed showed better characteristics than Experimental Example 7, but showed slightly lower characteristics than Experimental Example 9. Can be.

As described above, the organic light emitting display device according to an embodiment of the present invention comprises a first stack having a first light emitting layer in which phosphorescent and fluorescent blue dopants are mixed and a second light emitting layer in which phosphorescent green and red dopants are mixed. By forming the white light emitting organic light emitting diode including the two stacks, there is an advantage that the driving voltage, luminous efficiency, quantum efficiency and luminance characteristics are excellent.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It will be understood that the invention may be practiced. Therefore, the embodiments described above are to be understood as illustrative and not restrictive in all aspects. In addition, the scope of the present invention is shown by the claims below, rather than the above detailed description. Also, it is to be construed that all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts are included in the scope of the present invention.

1 is a view showing an organic light emitting display device according to a first embodiment of the present invention.

2 is a view showing a mechanism of a first light emitting layer of an organic light emitting display device according to a first embodiment of the present invention.

3 is a band diagram of an organic light emitting display device according to a first embodiment of the present invention;

4 is a view showing an organic light emitting display device according to a second embodiment of the present invention.

5 is a view showing an organic light emitting display device according to embodiments of the present invention.

6 is a graph showing the emission spectrum of the organic light emitting display device manufactured according to Experimental Examples 1 to 6 of the present invention.

7 is a graph showing an emission spectrum of the organic light emitting display device manufactured according to Experimental Example 7 to 9 of the present invention.

Claims (10)

An anode electrode; A first stack disposed on the anode and having a first light emitting layer comprising a phosphorescent blue dopant and a fluorescent blue dopant in one host; A charge generation layer located on the first stack; A second stack disposed on the charge generation layer, the second stack including a second light emitting layer including green and red dopants in one host; And An organic light emitting device comprising a cathode electrode located on the second stack. The method of claim 1, The first stack is, A first hole injection layer and a first hole transport layer formed between the anode electrode and the first light emitting layer; And An organic electroluminescent device further comprising a first electron transport layer and a first electron injection layer formed between the first light emitting layer and the charge generation layer. 3. The method of claim 2, The second stack, A second hole injection layer and a second hole transport layer formed between the charge generation layer and the second light emitting layer; And The organic light emitting device further comprises a second electron transport layer and a second electron injection layer formed between the second light emitting layer and the cathode electrode. The method of claim 3, wherein And an exciton blocking layer between the first hole transport layer and the first light emitting layer or between the second hole transport layer and the second light emitting layer. The method of claim 1, The second light emitting layer includes a phosphorescent or fluorescent green dopant and a phosphorescent or fluorescent red dopant in one host. An anode electrode; A first stack disposed on the anode and having a first light emitting layer including a green and a red dopant in one host; A charge generation layer located on the first stack; A second stack disposed on the charge generation layer, the second stack including a second light emitting layer including a phosphorescent blue dopant and a fluorescent blue dopant in one host; And An organic light emitting device comprising a cathode electrode located on the second stack. The method of claim 6, The first stack, A first hole injection layer and a first hole transport layer formed between the anode electrode and the first light emitting layer; And An organic electroluminescent device further comprising a first electron transport layer and a first electron injection layer formed between the first light emitting layer and the charge generation layer. The method of claim 7, wherein The second stack, A second hole injection layer and a second hole transport layer formed between the charge generation layer and the second light emitting layer; And The organic light emitting device further comprises a second electron transport layer and a second electron injection layer formed between the second light emitting layer and the cathode electrode. The method of claim 8, And an exciton blocking layer between the first hole transport layer and the first light emitting layer or between the second hole transport layer and the second light emitting layer. The method of claim 6, The second light emitting layer includes a phosphorescent or fluorescent green dopant and a phosphorescent or fluorescent red dopant in one host.

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