US 11,702,591 B2
Fluorescent rare earth complex and security medium using the same
Hiroki Iwanaga, Yokohama (JP); and Kenji Miyazaki, Komae (JP)
Assigned to KABUSHIKI KAISHA TOSHIBA, Minato-ku (JP); and TOSHIBA INFRASTRUCTURE SYSTEMS & SOLUTIONS CORPORATION, Kawasaki (JP)
Filed by KABUSHIKI KAISHA TOSHIBA, Minato-ku (JP); and TOSHIBA INFRASTRUCTURE SYSTEMS & SOLUTIONS CORPORATION, Kawasaki (JP)
Filed on Mar. 13, 2020, as Appl. No. 16/818,726.
Claims priority of application No. 2019-163001 (JP), filed on Sep. 6, 2019.
Prior Publication US 2021/0071073 A1, Mar. 11, 2021
Int. Cl. H01L 51/50 (2006.01); C09K 11/06 (2006.01); F21K 2/00 (2006.01); C07F 9/53 (2006.01); C07F 5/00 (2006.01)
CPC C09K 11/06 (2013.01) [C07F 5/003 (2013.01); C07F 9/5345 (2013.01); F21K 2/00 (2013.01); C09K 2211/182 (2013.01)] 26 Claims
OG exemplary drawing
 
6. A rare earth complex comprising:
a rare earth ion,
a diphosphine dioxide ligand, and
a β-diketone ligand
wherein two phosphorus atoms contained in said diphosphine dioxide ligand individually have substituents different from each other, which is a polynuclear complex comprising two or more rare earth ions and having a structure in which two rare earth ions are bridged with said diphosphine dioxide ligand alone.
 
7. A rare earth complex mixture which contains two or more rare earth complexes comprising
rare earth ions,
diphosphine dioxide ligands, and
β-diketone ligands
wherein said mixture contains at least two rare earth complexes selected from the group consisting of:
(a) a first rare earth complex comprising
said rare earth ion,
one of said diphosphine dioxide ligands, and
three of said β-diketone ligands;
(b) a second rare earth complex comprising
said rare earth ion,
two of said diphosphine dioxide ligands, and
two of said β-diketone ligands; and
(c) a third rare earth complex comprising
said rare earth ion,
one of said diphosphine dioxide ligands, and
two of said β-diketone ligands
provided that
two phosphorus atoms contained in each said diphosphine dioxide ligand individually have substituent sets different from each other.