RECOVERY OF PIGMENT FROM WATER INK

摘要

PURPOSE:To recorver pigments separately classibying by their color, in recovering the pigments from waste ink, by reparating each layer of the pigment by utilizing the difference of the floating or precipitating speed of pigment particles. CONSTITUTION:Waste ink is supplied to a mixing tank M from a line 2 while a diluting solvent is supplied thereto from a tack T3 to be mixed while the ratio of diluting solvent 1 waste ink is adjusted to 0.1-3 and the obtained mixture is sent to a dipersing tower D. To said dispersing tower D, a solbent poor in dispersibility for the pigment but good in solubility to resins is supplied at a constant speed as a rising stream and pigment particles in the waste ink are reparated into plural layers by the difference of bloating or precipitating speed while withdrawn in separated layers from lines 11-15 to be sent to a solid- liquid separators S1-S5. As the rising solvent, an aromatic hydrocarbon such as toluene or xylene is preferred and used as a mixture with ethyl acetate or the like and the rising speed is pref. 0.05-1.0mm./sec.