| 摘要 |
PROBLEM TO BE SOLVED: To provide a process for producing a water-base pigment color ink composition suitable for use in ink jet printing. SOLUTION: A water-soluble initiator being an inorganic persulfate is added in the presence of an organic monomer phase containing a carboxylic acid, an oil-soluble chain transfer agent and a partially water-soluble chain transfer agent and a water phase containing a nonionic surfactant and an anionic surfactant, and the resulting mixture is subjected to polymerization to obtain a latex containing carboxylic acid carrying polymer particles. The obtained latex particles and a colorant are coagulated, and an effective amount of an anionic surfactant is added to the agglomerates under agitation. The obtained mixture is heated to a temperature substantially equal to or higher than the glass transition point of the polymer. |
