|1.Research Institution||Osaka University|
|2.Research Area||Physical and Engineering Sciences|
|4.Term of Project||FY 1997 〜 FY 2001|
|6.Title of Project||Creation of Photo- and Electroactive Organic Materials and their Applications for Photonic Devices|
|Name||Institution,Department||Title of Position|
|Yasuhiko Shirota||Osaka University, Graduate School of Engineering||Professor|
|Names||Institution,Department||Title of Position|
|Tomiki Ikeda||Tokyo Institute of Technology, Research Laboratory of Resources Utilization||Professor|
|Takatomo Sasaki||Osaka University, Graduate School of Engineering||Professor|
|Ken-ichi Machida||Osaka University, Collaborative Research Center for Advanced Science and Technology||Professor|
9.Summary of Research Results
* Several new concepts for the molecular design of amorphous molecular materials for use in organic light-emitting
diodes (OELDs) have been presented, and novel families of hole-transporting, electron-transporting,
hole-blocking, and emitting amorphous molecular materials were designed and synthesized. These materials
permitted the fabrication of thermally stable, high performance OLEDs. Multi-color OLEDs using novel
emitting amorphous molecular materials were also developed.
* Photochromic amorphous molecular materials based on azobenzene and dithienyethene were created and their photochromic properties in the amorphous film were elucidated. Formation of surface relief grating with high diffraction efficiency and dual image formation at the same location were realized using these materials.
* A photorefractive device using an amorphous molecular material as a hole-transporting host was developed. It is shown that the device exhibits a large photorefractive effect at zero electric field in the absence of the poling process.
* Novel photochromic liquid-crystalline materials were designed and synthesized. It was found that photochemical liquid crystalline-to-isotropic phase transition can be induced by photochemical reactions of photochromic materials in nanosecond timescale and that the reorientation of liquid crystalline molecules was brought about with the molecular long axis perpendicular to the polarization direction of light. Holographic materials using these photochromic liquid-crystalline molecules were developed.
* New techniques for the growth of high quality organic single crystals were developed. High quality nonlinear optical crystals were successfully grown by using these new techniques.
* A series of silica-based hybrid materials containing rare-earth complexes were prepared by the sol-gel method. The luminescence characteristics were investigated. The hybrid materials containing europium (III) crown ether complexes have been found to exhibit good persistent spectral hole-burning characteristics that the holes persist even at room temperature.
(1)Photonics、(2)Amorphous Material、(3)Single Crystal
(4)Liquid Crystal、(5)Hybrid Material