| 摘要 |
PROBLEM TO BE SOLVED: To provide a reversible thermochromic water-based ink composition, which exhibits favorable writing performance of suppressing handwriting from lightening or deepening of color, in particular, without lightening of color of handwriting in an erect state with time and without lightening of color of handwriting caused by vibration during transportation or carrying, in which no putrefaction caused by mold generation and proliferation of microorganisms takes place even after stored for a long period, and which is excellent in an antibacterial effect on toxic bacteria, and to provide a writing utensil and a writing utensil set using the same.SOLUTION: A water-based ink composition for a reversible thermochromic writing utensil composed of: water; a water soluble organic solvent; a reversible thermochromic microencapsulated pigment containing a reversible thermochromic composition comprising (i) an electron-donating colorable organic compound, (ii) an electron-accepting compound, and (iii) a reaction medium which determines a temperature for inducing a coloring reaction of the former two; a comb-shaped polymer dispersant having a carboxyl group on a side chain; a water soluble resin; a sugar alcohol having 3 or more carbon atoms; and an antiseptic agent having a cationic property, and a writing utensil 1 and a writing utensil set using the same, are disclosed. |
