THERMOCHROMIC WRITING INSTRUMENT

PROBLEM TO BE SOLVED: To provide a thermochromic writing instrument capable of preventing a friction body from becoming dirty when not in use.SOLUTION: A thermochromic writing instrument comprises a friction part 31 made of a low abrasive elastic material which can heat-discolor writing by frictional heat generating when the writing of the thermochromic ink is rubbed, and in which the thermochromic ink is accommodated, at an end part of a cylindrical body 2. On an outer surface of an end part on the friction part 31 side of the body 2, a protective member 4 is provided for surrounding an outer periphery of the friction part 31. The protective member 4 is provided in a manner movable in an axial direction, and it is always energized frontward in the axial direction by a resilient body 5. When the friction part 31 is not in use, a top part of the protective member 4 projects further frontward in the axial direction than a top part of the friction part 31. When the friction part 31 is in use, the protective member 4 moves backward in the axial direction by a contact between a writing surface 6 and the top part of the protective member 4.