Patent ID: 8282299
Filing Date: 2012-10-09
Classification: B43K,B43L,C09D

Abstract:
1. A writing instrument for producing thermochromic handwriting comprising: a friction body that produces frictional heat allowing development, disappearance or change of color of handwriting formed with the writing instrument, wherein the writing instrument is configured to use a coloring agent being a microencapsulated pigment prepared by enclosing in microcapsules a reversibly thermochromic composition which contains at least three essential ingredients: (a) an electron-donating color-showing organic compound; (b) an electron-accepting compound; and (c) a reaction medium determining the temperature at which color reaction between (a) and (b) takes place, and whose color disappears by heating, the coloring agent having a completely decolorizing temperature within a range of from 50° C. to 80° C., wherein the friction body has a friction coefficient of 0.4 to 0.8 when rubbed against a paper surface.