Sulfide Solutions as Inkjet Inks for Color-changeable Ag Films

Abstract

A novel and easy method for preparing color-changeable Ag films/plates was discovered using aqueous solutions of sulfides as coloring agents. In the presence of specific sulfides such as lime sulfur solutions, the color of Ag films/plates, initially sliver, changes to yellow, red and blue depending on the preparation conditions such as the dipping time in the solutions and the temperature of the solution. One of the potential candidates is in the application as imaging materials. Assuming the imaging by inkjet devices, we have already investigated the ink receiving nature to Ag films/plates. The focus of this present work is to explore the nature of sulfide solutions which act as inks for changing the color of Ag films in the inkjet system. We found that both the solubility of sulfides in water and the nature of the hydrolyzed constituents of sulfides are important parameters for obtaining successful color-changeable Ag films in this imaging system. For example, K₂S solution works well as coloring agent due to its appropriate solubility in water and KSH, one of the hydrolyzed constituents of K₂S, play an important role to change the color of Ag films/plates.