| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a pencil lead excellent in the balance of bending strength and density. <P>SOLUTION: The pencil lead uses at least a constitutional material and a coupling material as main materials, and is formed by being applied with mixture, molding and burning treatment. The pencil lead contains, in a pencil lead body, inorganic particles other than graphite whose particle diameters are not smaller than 0.1 μm and smaller than 1.0 μm. <P>COPYRIGHT: (C)2012,JPO&INPIT |
