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As the electronic device market has expanded, image sensors have attracted much attention. In order to develop a high performance image sensor, the unit pixel size of the image sensor is gradually ...

Inkjet technology using pigment requires pigment dispersity as well as the stability in solvents. New synergist PY-150ASA2 was synthesized by substituting 1,4-butane sultone in order to give the di...

New green emitting compounds based on tris(N-methylindolo)benzene (NMT), anthracene and pyrene were synthesized. NMT-An and NMT-Py were used as an emitting layer in OLED device to examine emitting property. OLED device containing NMT-An emitting layer and conventional hole transporting layer (HTL) of NPB was found to exhibit better characteristics compared to NMT-Py. And that device showed maximum EL emission at 502 nm and 550 nm, CIE coordinates (0.38, 0.48), and a luminance efficiency of 2.06 cd/A. Also when NMT and NMT-An were used as a HTL instead of NPB, the device including NMT-An emitter showed 2.67 cd/A and 2.29 cd/A in luminance efficiency.

Two emitting compounds, 9,10-bis-[1,1′;3′,1′′]terphenyl-5′-yl-1,5-di-o-tolyl-anthracene [TP-DTA-TP] and 9,10-bis-phenyl[1,1′;3′,1′′]triphenyl-5′-yl-1,5-di-o-tolyl-anthracene [TPB-DTA-TPB] based on new twisted core moiety were synthesized through boration, Suzuki reaction, and Sandmeyer reactions. EL performance was improved by varying the chemical structure of the side group. Physical properties such as optical, electrochemical, and electroluminescent properties were investigated. Synthesized compounds were used as an EML in OLED device: ITO / 2-TNATA (60nm) / NPB (15nm)/ TP-DTA-TP or TPB-DTA-TPB (35 nm) / Alq3 (20nm) / LiF (1nm) / Al (200nm). It was found that TPB-DTA-TPB showed higher luminance efficiency and better C.I.E. value than TP-DTA-TP device.

Three new emitting compounds of 5P-VCB, 5P-VAn and 5P-VPy for OLED based on hexaphenylbenzene moiety were synthesized. Physical properties by the change of the substitution groups of the synthesized materials were systematically examined. Photoluminescence spectrum of the synthesized materials showed maximum emitting wavelengths of about 420∼487 nm in solution state and 452∼488 nm in film state, indicating blue emission color. OLED devices were fabricated by the synthesized compounds using vacuum deposition process as an emitting layer. Current efficiencies and CIE values of 5P-VCB, 5P-VAn and 5P-VPy were 1.76, 0.38 and 7.91 cd/A and (0.15, 0.07), (0.20, 0.31) and (0.20, 0.36), respectively.

Two color white organic light-emitting diode (WOLED) that uses a co-host system in a solution process method was achieved. The device configuration was ITO/PEDOT:PSS (40 nm)/emitting layer (50 nm) / BCP (10nm) / Alq3 (20 nm) / LiF (1 nm) / Al. The emitting layer consists of two co-hosts of TATa and NPB and dopants of DPAVBi (blue) and rubrene (yellow). As the ratio of the host material NPB was increased, the operating voltage of the device was reduced. Luminance efficiency and power efficiency were also increased according to the NPB ratio. For the white device using host of TATa 40%:NPB 60%, the efficiency was 5.17 cd/A and 3.23 lm/W with color coordinates of (0.29, 0.38).

Two color white EML is proposed by using blending and spin-coating method through a co-host/dopant system. Device performances were systematically compared based on the optical property of with/without interlayer PVK. When 1-[1,1’;3’,1’’]Terphenyl-5’-yl-6-(10-[1,1′;3′,1′′] terphenyl-5′-yl-anthracen-9-yl)-pyrene (TP-AP-TP) is a blue emitter with high luminance and external quantum efficiency, NPB is used as a co-host material which has HTL property and wide band gap like a blue emitter. DPAVBi and Rubrene were each used as blue dopant and yellow dopant. Luminance efficiency of the device used interlayer was 4.31cd/A, a value 30% higher than without interlayer (3.31 cd/A) at 10 mA/cm2.

A triyne monomer was prepared by the reaction of oxotremorine and propargyl bromide. A new conjugated polymer was prepared by the double cyclopolymerization of triyne monomer by using transition me...