To provide an ink stock solution giving an ink composition and having excellent storage stability and handling property, an ink stock solution enabling high-density printing with excellent black tone without adding a large amount of a dye or other color correction dye, having high weather resistance and excellent heat-resistance, water resistance (bleeding resistance), hue and liquid stability, an ink composition produced by using the ink stock solution, and an inkjet recording method to use the ink composition.
The ink stock solution contains an aqueous medium and at least one kind of dye at a concentration of ≥3 mass% wherein the dye has a peak of absorption spectrum in the aqueous medium at 440-540 nm, its half-value width of 90-200 nm and an HPLC purity of 80-95%. The invention further provides an ink composition produced by using the ink stock solution and an inkjet recording method to use the ink composition.
WACHI NAOTAKA
Hironori Honda
Toshimitsu Ichikawa
Takeshi Takamatsu
Kiyozumi Yazawa