INK FOR INK JET PRINTING, AND LIQUID DEVELOPING AGENT COMPOSITION BOTH CONTAINING COLORED SILICA PARTICLE

摘要

Ink jet inks and liquid developers are disclosed which contain coloured particles comprising hydrophilic silica particles, to the surfaces of which dyes are covalently bonded through silane coupling agents. The ink jet inks generally comprise a liquid medium and a plurality of the coloured silica particles. The liquid developers generally comprise a liquid medium, a resin, a pluraltiy of the coloured silica particles, and a charge-control agent. The particles are prepared by a process which comprises reacting hydrophilic silica particles with a silane coupling agent in the absence of water to form particles having covalently attached thereto coupling agents, followed by reacting a dye with the coupling agent attached to the silica particles.