Abstract: A water based white color tone pigment ink for a ballpoint pen comprising titanium oxide having an oil absorption of 25 (g/100 g) or less and an average particle diameter of 400 nm or less, a water soluble resin, a thickener, water and a polar solvent, which can provide drawn lines to be excellent in developing colors such as a white color and a poster color regardless of a color tone of writing paper and which can cover or correct drawn lines printed by means of a writing instrument, a type writer and a copying machine.

Abstract: Provided is a water based ink composition for a ball point pen comprising at least one selected from the group consisting of an alkylene oxide adduct of polyglycerin, an alkylene oxide adduct of glycerin and an alkylene oxide adduct of trimethylolpropane and further comprising a colorant, a white plastic pigment, a viscosity-controlling agent and water. The ink composition is excellent in a writing property as well as a coloring property of the drawn lines regardless of the kind of writing paper and is stable with the passage of time. In addition thereto, it provides the drawn lines with a color having the same color tone as that of the visual color when it is charged into an ink reservoir.

Abstract: Provided is a water based white color tone pigment ink for a ballpoint pen comprising titanium oxide, a complementary colorant comprising a pigment or a pseudo pigment obtained by dyeing resin particles with a dye, a resin emulsion, a thickener, water, a polar solvent and other additives, wherein the pigment has an average particle diameter of 100 nm or more; the pseudo pigment has an average particle diameter of 200 nm or more; the resin contained in the resin emulsion has an average particle diameter of 200 nm or more; and the ink has a viscosity of 500 mPa·s to 5000 mPa·s. Vivid drawn lines having a poster color tone can be obtained well even on writing paper having a dark hue. The ink is stable even in long term storage and excellent in a follow-up property and can write continuously.