| 摘要 |
PROBLEM TO BE SOLVED: To provide a water-based pigment ink composition set allowing prevention of a color bleeding, etc., even at the boundary between a high-brightness color and a low-brightness color. SOLUTION: This ink set is obtained by selecting the ink having lowest brightness so as to have highest surface tension and the ink having highest brightness so as to have lowest surface tension and preparing the inks so that (1) the ink having lowest brightness comprises an anionic surfactant and the ink having highest brightness comprises an ampholytic surfactant or (2) the ink having lowest brightness comprises the ampholytic surfactant and the ink having highest brightness comprises the anionic surfactant (a) when dispersed pigments in the inks having lowest brightness and highest brightness are anionic or (1) the ink having lowest brightness comprises a cationic surfactant and the ink having highest brightness comprises an ampholytic surfactant or (2) the ink having lowest brightness comprises the ampholytic surfactant and the ink having highest brightness comprises the cationic surfactant (a) when dispersed pigments in the inks having lowest brightness and highest brightness are cationic. |
