To provide a method for producing a condensed disazo pigment excellent in light resistance and dispersibility, and capable of providing an ink jet-recording liquid capable of providing a printed product excellent in water resistance, the light resistance and transparency by kneading a specific compound, a water-soluble inorganic salt and a water-soluble solvent, and forming the kneaded material into a minute product.
(A) A compound of the formula (R is methyl or chlorine; A is methyl or H; B is trifluoromethyl or chlorine; D is H, methyl or p-chlorophenoxy) is kneaded with (B) a water-soluble inorganic salt (e.g. sodium chloride) and (C) a water-soluble solvent (e.g. diethylene glycol), and the kneaded product is formed into a minute product to provide the objective pigment, preferably having 60-200 m2/g specific surface area, 5-150 nm average primary particle diameter and an average ratio of the length to the width regulated so as to be (1:1)-(5:1) in the method for producing the condensed disazo pigment. The amount of the used component B is preferably 2-20 times, more preferably 3-10 times as much as the amount of the component C expressed in terms of weight. The amount of the used component C is 0.5-10 times as much as that of the component A.
TOYODA ICHIRO