| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a friction body which selectively and easily discolors only an image, formed from a reversible thermochromic ink, and a microarea part of handwriting, without requiring a strong pressing force during scratching, or increasing the number of the times of the scratching. <P>SOLUTION: The friction body discolors the image with reversible thermochromism to a second state from a first one by frictional heat. When the friction body is pressed against the top of a glass plate by a load of 1,000 g, a contact area of the friction body is in the range of 0.5-15 mm<SP>2</SP>. A writing instrument with the built-in reversibly thermochromic ink is equipped with the friction body. A writing instrument set comprises the friction body, and the writing instrument with the built-in reversibly thermochromic ink. <P>COPYRIGHT: (C)2007,JPO&INPIT |
