| 摘要 |
PROBLEM TO BE SOLVED: To provide a pigment having a high-quality back color phase with excellent moisture resistance, bronze resistance, light fastness, (ozone) gas resistance and storage stability in an aqueous solution, a high print density, and low color saturation and color rendering and an ink composition containing the pigment, especially an ink composition for ink jet recording.SOLUTION: Azo compounds of the following formula and their tautomers and salts are provided. In the formula, Ris e.g. a methyl group; Ris e.g. a sulfo group; Rto Rare independently e.g. a 1-4C alkylthio group having a substituent; Rto Rare independently e.g. a 1-4C alkylcarbonylamino group; Rand Rare independently e.g. a 1-4C alkoxy group; and Rand Rare independently e.g. a sulfo group. |
