Patent attributes
A self-dispersible bipyridine-based metal complex includes a bipyridine-based ligand and a metal, and an ink composition including the metal complex. The bipyridine-based metal complex may be self-dispersed without requiring a dispersing agent and may be used as a colorant per se. Furthermore, the metal complex, when binding with a common colorant, may produce various colors and exhibit enhanced durability including light resistance. In addition, the metal complex includes a hydrophilic group-containing ligand coordinating with the metal, in addition to the bipyridine-based ligand, and thus, has a bulky structure. Therefore, dispersion stability is enhanced by a self-dispersion system based on a steric hindrance due to the bulky structure of the metal complex and an electrostatic repulsive force between the charged metal and the hydrophilic group-containing ligand, thus enhancing a long-term storage stability.
