| 摘要 |
PROBLEM TO BE SOLVED: To obtain an ink improved in deliverability and preservability, excellent in water resistance, capable of giving highly dense images, and useful in ink jet printers, by incorporating an aqueous medium with specific carbon black and a water-soluble resin, etc. SOLUTION: This ink is obtained by incorporating 50-75 wt.%, based on the total weight of the ink, of ion-exchanged water with (A) carbon black <=120 g/L in bulk density and 0.01-0.03 μm in particle size, (B) a water-soluble styrene-(meth)acrylic acid-(meth)acrylic ester copolymer 3,000-20,000 in weight- average molecular weight and 100-250 in acid value made from 5-40 wt.% of styrene, 30-90 wt.% of (meth)acrylic acid and 5-70 wt.% of a (meth)acrylic ester, (C) 10-40 wt.%, based on the total weight of the ink, of a polyhydric alcohol such as glycerol, and (D) <=10 wt.%, based on the total weight of the ink, of an aliphatic monohydric alcohol such as ethyl alcohol in a weight ratio A/B of (2:1) to (10:1). |
