| abstract |
The invention provides a pigment dispersion coagent, which may be produced at a high efficiency by using concentrated sulfuric acid or oleum, and may exhibit an excellent pigment dispersability by employed in conjunction with a pigment dispersant. The feature of the pigment dispersion coagent is that it is a compound represented by the following general formula (1) [where M represents H, Na, K, NH.sub.4 or NR.sup.1R.sup.2R.sup.3R.sup.4 (R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are the same or different, and represent substitutable saturated or unsaturated aliphatic hydrocarbon groups of 1 to 10 carbon atoms, or substitutable aromatic hydrocarbon groups of 6 to 10 carbon atoms); m represents an integer of 1 or more]. |