Hydrophobization of inkjet ink to improve drinking efficiency

摘要

Traditional flotation inkjet deinking has not been successful due to the hydrophilic nature as well as the submicron size of the ink. Furthermore, the pulping and deinking procedures of traditional hydrophobic ink and inkjet ink are always contradictory. Thus, it is much more difficult to remove ink in mixed printed paper. One possible solution for this challenge is to change the surface property of inkjet ink and increase the particle size by chemical reaction to solve the problem of mixed printed paper deinking. The inkjet consists of insoluble pigment particle with adsorbed hydrophilic polymers such as polyacrylamide and polyacrylate homopolymers and copolymers. The carboxylic acid group in the stabilizing polymers is the main reason for the hydrophilicity. Thus if the polymers can be reacted to produce hydrophobic segments, the surface property of the ink will turn to hydrophobic. In addition, the hydrophobic particles are easier to agglomerate. The coagulation and stability of pigment ink particles was measured using various methods including dynamic light scattering and zeta potential. Additionally, the hydrophobicity of the pigmented inkjet ink was measured using measurement methods such as contact angle. Using these measurements, the coagulation and hydrophobization of the inkjet ink was analyzed for various process parameters including reaction temperature and time, solution pH, and reactants used.