An erasable ink composition comprising water, a water-soluble organic
solvent, and the following colorant, colorless resin particles and
shear-thinning, viscosity-adjustment agent, characterized in that the
colorless resin particles have a mean particle diameter smaller than that
of the colorant and are contained in an amount larger than that of the
colorant: (a) 3 to wt % (based on the whole ink) of colorless resin
particles which are made of at least one resin selected from among
acrylic resins, urethane resins, silicone resins and melamine resins and
have a mean particle diameter of 0.10 to 10 .mu.m, (b) 1 to 40 wt %
(based on the whole ink) of a colorant having a mean particle diameter of
2 .mu.m or above, and (c) 0.01 to 4 wt % (based on the whole ink) of a
shear thinning, viscosity-adjustment agent.