Patent ID: 7708913

Claim:
A writing implement comprising: an ink composition that reversibly turns from a colored state to a colorless state for the writing implement; and a frictional body for erasing a colored writing formed by the ink composition, wherein the ink composition comprises a thermochromic coloring color-memory microcapsule pigment comprising a thermochromic coloring color-memory composition in a colored state, the thermochromic coloring color-memory composition comprises a homogeneous solubilized mixture of (A) an electron donative coloring organic compound, (B) an electron accepting compound and (C) an ester compound represented by the following formula (1) as a reaction medium which controls color reactions of the components (A) and (B): wherein R represents an alkyl group or an alkenyl group, having 4 to 12 carbon atoms, a complete decoloring temperature (T 4 ) of the thermochromic coloring color-memory composition is 50° C. to 70° C., a coloring starting temperature (T 2 ) of the thermochromic coloring color-memory composition is 0° C. or lower regarding the color density-temperature curve, and the thermochromic-coloring color-memory composition has color-memory ability at the ordinary temperature range.