Patent attributes
A metallic colloidal solution (a) includes a water-based dispersion medium that is easy in handling with regard to safety and environment and metallic particles having a uniform particle diameter and being excellent in properties such as conductivity and (b) has properties suitable for various printing methods and ink-applying methods. In addition, an inkjet-use metallic ink incorporating the metallic colloidal solution has properties suitable for the inkjet printing method. The metallic particles are deposited by reducing metallic ions in water and have a primary-particle diameter of at most 200 nm. The dispersion medium is made of a mixed solvent of water and a water-soluble organic solvent. The metallic particles are dispersed in the dispersion medium under the presence of a dispersant having a molecular weight of 200 to 30,000.