PURPOSE: To obtain the above composition having excellent storage stability, erasability and fluidity, by blending ink with pigment, a resin having a specific film-forming temperature, organic solvent and water in a specific ratio.

CONSTITUTION: Ink is blended with (A) 1W50% pigment such as carbon black or phthalocyanine Blue, (B) 3W50% resin (e,g., acrylic resin, acryl-styrene copolymer resin, ethylene-vinyl acetate-vinyl chloride copolymer resin, acryl-vinyl acetate resin, carboxylated SBR or styrenic resin) having ≥40°C (preferably ≥50°C) film-forming temperature, (C) 0.5W50% organic solvent comprising a (di)alkylene glycol, polyalkylene glycol or glycerin and (D) 7W60% water.