Writing implements for forming thermochromic handwriting

摘要

[Solving Means] The present invention is intended to achieve a writing instrument excellent in handwriting density and temporal stability. [Solution] A writing instrument characterized by comprising a ball-point pen tip attached to the front end portion of the ink storage cylinder; and a ball-point pen refill having an ink composition for a writing instrument loaded therein; wherein said ink composition for a writing instrument is a thermochromic ink containing at least a thermochromic microcapsule pigment; wherein said writing instrument including a pressurization mechanism for applying a pressure to the back end of said ink composition for a writing instrument.