Invented by Seok-Jong Lee, Seung-gak Yang, Hee-Yeon Kim, Young-Kook Kim, Seok-Hwan Hwang, Dae-Yup Shin, Young-rag Do, Dong-Hyun Jung, Samsung Display Co Ltd
Organic electroluminescent devices are based on organic materials that emit light when an electric current is passed through them. These devices offer several advantages over traditional lighting technologies, including high energy efficiency, thin and flexible form factors, and excellent color reproduction. OLEDs have found widespread use in display technologies, such as smartphones, televisions, and wearable devices, due to their ability to produce vibrant and high-contrast images.
On the other hand, compound electroluminescent devices, particularly QLEDs, are based on quantum dots, which are tiny semiconductor particles that emit light when excited by an electric current. QLEDs offer several advantages over OLEDs, including higher brightness, longer lifespan, and better color accuracy. These devices are increasingly being used in high-end televisions and monitors, as well as in the automotive industry for advanced lighting applications.
The market for both organic and compound electroluminescent devices is driven by several factors. Firstly, the growing demand for energy-efficient lighting solutions is fueling the adoption of OLEDs and QLEDs. These devices consume less power compared to traditional lighting technologies, resulting in significant energy savings. Moreover, the increasing focus on sustainability and environmental conservation is driving the demand for eco-friendly lighting solutions, further boosting the market for organic and compound electroluminescent devices.
Secondly, the rapid advancements in display technologies are also contributing to the market growth. OLEDs and QLEDs offer superior image quality, higher resolution, and wider viewing angles compared to conventional LCD displays. As a result, there is a growing demand for these devices in the consumer electronics industry, particularly in smartphones, televisions, and virtual reality headsets.
Furthermore, the automotive industry is emerging as a significant market for organic and compound electroluminescent devices. The ability of OLEDs and QLEDs to provide customizable and dynamic lighting solutions is driving their adoption in automotive lighting applications. These devices can create unique lighting effects, enhance safety by improving visibility, and contribute to the overall aesthetics of vehicles.
However, despite the numerous advantages and market opportunities, there are still challenges that need to be addressed. One of the major challenges is the high manufacturing cost of organic and compound electroluminescent devices. The complex production processes and the need for specialized equipment contribute to the overall cost, making these devices relatively expensive compared to traditional lighting technologies.
Additionally, the limited lifespan of organic electroluminescent devices is a concern for some applications. OLEDs have a shorter lifespan compared to QLEDs, which can affect their suitability for certain industries, such as outdoor signage and commercial lighting. However, ongoing research and development efforts are focused on improving the durability and longevity of these devices.
In conclusion, the market for organic and compound electroluminescent devices is experiencing significant growth due to their unique properties and applications. The demand for energy-efficient and eco-friendly lighting solutions, advancements in display technologies, and the automotive industry’s need for innovative lighting solutions are driving the market. Despite challenges such as high manufacturing costs and limited lifespan, ongoing research and development efforts are expected to further enhance the performance and market potential of these devices.
The Samsung Display Co Ltd invention works as follows
A blue phosphorescent compound is an Ir compound.” Such a material can be used in an organic electroluminescent product. The Ir compound can be used to create an organic layer such as a layer that emits light. A device that emits dark-blue light and has a high-purity organic layer can be an organic electroluminescent. This organic electroluminescent product may be low-power consumption.
Background for Ir organic and compound electroluminescent devices using the same
This application claims the benefit from Korean Patent Application No. The Korean patent application No. 10-2004-0006592 was filed on February 2, 2004 and is hereby incorporated in its entirety.
The present invention is an Ir compound, and an electroluminescent organic device that uses the Ir compound. More specifically, it is an Ir-containing blue phosphorescent organic metal compound, a manufacturing method, and a device using an Ir compound.
In a conventional electroluminescent device (EL), an anode on a substrate is formed. On the anode, successively, a hole transporting, a light-emitting, an electron transporting, and cathode layer are deposited. “The hole transporting, light emitting, and electron transporting layers are all made of organic compounds.
When a voltage applied to both the anode (cathode) and the anode (anode), holes from the anode migrate towards the emission layer through the hole transport layer. The electron transport layer injects electrons from the cathode into the light emitting layer. The electrons and holes then recombine at the emission layer, generating excitons. The fluorescent molecule in the emission layer emits a light when the excitons convert from an excited to a grounded state. This produces an image. “Fluorescence is the light emission that occurs when a single excited (S1) state is converted to a grounded state (SO), and phosphorescence is the light emission produced by a triplet (T1) excited state being converted to a base state (SO).
With regard to fluorescence the proportion of singlet excited states is 25% (the percentage of triplet excited states is 75) and there is thus a limit on light emission efficiency. In phosphorescence the proportions of triplet and singlet excited states may be 75 and 25 respectively. The theoretical quantum efficiency could reach 100%.
Light-emitting materials using T1 are being developed. Princeton University and South California University, for example, have developed phosphorescent material using Ir and platinum compounds [Sergey Lamansky and others]. Inorg. Chem. 40, 1704-1711 (2001) and J. Am. Chem. Soc., 123, 4304-4312, 2001]. Similarly, (4,6-F2ppy)2Irpic [Chihaya Adachi et al. Appl. Phys. Lett., 79: 2082-2084 (2001)] and an Ir-compound with a fluorinated Pppy ligand. [Vladimir V. Grishin etc. Chem. Commun. 1494-1495 2001] as a material that emits blue light. However, (4.6-F2ppy 2Irpic emits a light with a region of blue sky. The shoulder peak of (4.6-F2ppy2Irpic) is also large, increasing the y-value of color purity on the NTSC chromaticity chart. A host material for blue light-emitting material has yet to be developed. Blue light emitting materials are less efficient and have a shorter lifetime than red or green phosphorescent material. “Therefore, we need a material that emits dark blue light, has high efficiency and a long lifespan.
The present invention is a dark-blue phosphorescent material with high color purity, and low power consumption.
The present invention also provides a organic electroluminescent devices using a blue-phosphorescent compound either as a coloring material or dopant materials.
The present invention provides a Ir compound represented in formula 1:
Where A can be either ‘C(R4)’ or?N? A may be either?C(R4)? B can be either ‘C(R7)’ or?N? B may be either?C(R7)? “N” or?N?
The present invention provides an organic electroluminescent apparatus that includes an organic film interposed in between two electrodes. The organic film can be made of an Ir-compound.
The present invention, for example provides an Ir compound represented as formula 1. “The Ir compound may be represented by formulae 2 or 3, depending on the combination m and N.
in which R1-R6 may be the same formula as in Formula 1″.
In formulas 1-3, X is a monoanionic bidentate ligand such as acetylacetonate (acac), hexafluoroacetylacetonate (hfacac), picolinate (pic), salicylanilide (sal), quinolinecarboxylate (quin), 8-hydroxyquinolinate (hquin), L-proline (L-pro), 1,5-dimethyl-3-pyrazole carboxylate (dm3pc), imineacetylacetonate (imineacac), dibenzoylmethane (dbm), tetrametyl heptandionate (tmd), 1-(2-hydoxyphenyl) pyrazolate (oppz), or phenylpyrazole (ppz). The following compounds can be represented as formula 4:
The compound A in formula 2 or 3 can be either C(R4). “In the compound represented by formulas 2 or 3, A may be either?C(R4)? The R1 and R2 may all be H. R3 can be either H or an electron-donating group like a Dimethylamino, Diaphenylamino, Pyrolidine, Phenyl or Isopropyl Group. B may be either?C(R7)? ; R5, R6, and R7 may each independently be H, or an electron withdrawing group such as F, a cyano group, a nitro group, a substituted benzene with F or a trifluoro methyl group, or a trifluoro methyl group; and X may be a material such as acetylacetonate (acac), hexafluoroacetylacetonate (hfacac), picolinate (pic), salicylanilide (sal), quinoline carboxylate (quin), 8-hydroxyquinolinate (hquin), L-proline (L-pro), 1,5-dimethyl-3-pyrazolecarboxylate (dm3pc), imineacetylacetonate (imineacac), dibenzoylmethane (dbm), tetrametyl heptandionate (tmd), 1-(2-hydoxyphenyl) pyrazolate (oppz), or phenylpyrazole (ppz).
In Formulas 1-3 when A is either C(R4) or N? “In formulas 1-3, when A is either?C(R4)? All of R1, R2, R4 are hydrogen, R3 can be either H or an electron-donating group like a dimethylamino, a diphenylamino, a trimethylamino, or a biphenylamino; B could be either?C (R7)? B may be either?C(R7)? “N
Examples of the synthesis are given for a first compound (19), second compound (33) a third (136), fourth (138) and fifth (142). The present invention, however, is not limited to the compounds described. “Tables 1 and 2, respectively, show compounds that are represented by formulas 2 or 3.
The compounds represented by formulas 2, 3 and 4 are blue phosphorescent compounds with high color purity and excellent emission efficiency.
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