A pigment dispersant contains the following component (a) alone or the following components (a) and (b) in combination: Component (a): a composite pigment formed of a diketopyrrolopyrrole pigment having a sulfonic group and another diketopyrrolopyrrole pigment having no sulfonic group, wherein the number of sulfonic group per molecule of the diketopyrrolopyrrole pigments in the composite pigment is from 0.05 to 0.5; and Component (b): a pigment other than the component (a), wherein the pigment has a sulfonic group or its metal salt, ammonium salt or amine salt. Also disclosed are a colored composition for color filters, a process for the fabrication of a color filter, the color filter fabricated by the process, an image display device including the color filter, and an information communication equipment including the image display device. These colored composition, process, color filter, image display device and information communication equipment all make either direct or indirect use of the pigment dispersant.