Tokyo — Mitsubishi Chemical Corporation (MCC) announced here that it has developed new blue phosphorescence Organic Light-Emitting Diode (OLED) material that can be manufactured at lower cost than other OLED processes.
The company said its breakthrough technology uses a lower-cost, wet-coating process which could evolve into a production technique for the manufacture of large flat-panel OLED displays.
OLED devices emit light when an electric current is applied and do not require a backlight to function. They consume less power, have a wider viewing angle and display a brighter image with a refresh rate that is a thousand times faster than LCDs.
Current applications of OLED technology are limited to smaller display screens of mobile phones, car audio, portable music players and similar products because of the difficulty applying current OLED technologies to large screens.
The research center of MCG has been developing phosphorescence-emitting layer material, suitable for manufacturing a thin, bright large-screen display, the company said.
The company said phosphorescent material has four times greater luminous efficiency in principle than that of fluorescent material, which is widely used today.
“This higher efficiency of phosphorescence leads to low power consumption, which is critical for applications using larger screens such as flat-panel television screens,” MCG said in a prepared statement. “In addition, the wet-coating method enables low-cost processing and makes practical the fabrication of large-area screens, which has been difficult and expensive using standard vacuum deposition processes.”
The new OLED device employs blue phosphorescence host material, hole blocking material and hole injection material to achieve a 30cd/A efficiency at an intensity of 100 cd/m2 (external quantum efficiency: 13 percent), more than twice that of conventional blue wet-coating type OLEDs, the company said.
