INK COMPOSITION FOR REVERSIBLE THERMOCHROMIC WRITING IMPLEMENT, AND REVERSIBLE THERMOCHROMIC WRITING IMPLEMENT STORED THEREWITH

摘要

PPROBLEM TO BE SOLVED: To provide an ink composition for a reversible thermochromic writing implement capable of achromatizing the first handwriting at optional timing by a user, capable of restoring easily the achromatized handwriting, and capable of recognizing a content and erroneous writing after written, and a reversible thermochromic writing implement stored therewith. PSOLUTION: This ink composition for the reversible thermochromic writing implement contains two kinds of microcapsule pigments A, B including in each a reversible thermochromic composition and different in chromatic characteristics, a resin and a solvent, contains the microcapsule pigment A under a colored state, contains the microcapsule pigment B under an achromatic state, a complete achromatic temperature TSB4/SBof microcapsule pigment A is 30°C or more, as to a color density-temperature curve, a chromatism starting temperature TSB2/SBthereof is -50 to -20°C, a hysteresis width ▵H is within a range of 40-70°C, a complete achromatic temperature TSB4/SBof microcapsule pigment B is 45-95°C, and a chromatism starting temperature TSB2/SBthereof is within a range of -25 to 0°C. The writing implement storing the ink composition is disclosed. PCOPYRIGHT: (C)2009,JPO&INPIT