Low threshold organic reverse saturable absorber material

摘要

PROBLEM TO BE SOLVED: To provide a low threshold organic inverse-oversaturation absorbing material which shows a significant increase in the absorbance of the material by weak steady light such as light from an LED, a semiconductor laser and sun rays having an energy of not more than 1 W/cm² and in an order of several mW/cm² in air at a normal temperature, and allowing the formation of a medium having a large area.;SOLUTION: The inverse-oversaturation absorbing material comprises a matrix having a diffusion coefficient of smaller than 10^-15 cm²/s at a normal temperature and forming a disordered state a photosensitizer having an inter-system crossing efficiency of 50% or hig and a phosphorescent quantum efficiency of 0.1 sec or longer at room temperature and a dye having a long excited state lif, showing a phosphorescent life time of 0.3 sec or longer in a rigid medium at 77K. In the material, the lowest excited triplet energy of the photosensitizer is higher than the lowest excited triplet energy of the dye having a long excited state life, and the absorbance of the photosensitizer in the ground state at a wavelength of 400 to 600 nm is smaller than the absorbance of super-absorption in the excited triplet state of the dye having a long excited state life.;COPYRIGHT: (C)2011,JPO&INPIT