| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a fired lead for pencil, in which in the fired lead for pencil, because the bending strength decreases with the improvement of its writing concentration, the decrease in the bending strength is controlled while high writing concentration is obtained for further performance improvement of the fired lead for pencil, and that breaks an inverse correlation of conventional bending strength and concentration. <P>SOLUTION: The fired lead for pencil is obtained by calcining a composition that contains at least graphite; and a composite particle in which at least 40% of the organic particle surface is covered with an inorganic particle. The fired lead for pencil is obtained by calcining a composition in which at least 30 volume% of composite particle is included. <P>COPYRIGHT: (C)2013,JPO&INPIT |
