| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain the subject ink excellent in water resistance and continuous extrudability by dispersing or dissolving carbon black and a resin in an aqueous liquid to prepare a dispersion wherein the carbon black partially adsorbs the resin, and subsequently removing the non-adsorbed portion of the resin by an ultrafiltration method. SOLUTION: This method for producing an ink jet ink comprises dispersing or dissolving carbon black and a resin preferably such as an acrylic copolymer, e.g. an acrylic acid-styrene-α-methylstyrene terpolymer, in an aqueous solution to allow the carbon black to adsorb the resin preferably in an amount of 0.05-0.5 pt.wt. per 1 pt.wt. of the carbon black, and subsequently removing at least a part of the non-adsorbed resin by an ultrafiltration method using an ultrafiltration membrane having a fractionation mol.wt. of 50,000-400,000 to obtain the objective ink wherein the concentration of the non-adsorbed resin is 0.001-1.0 wt.%.</p> |
