| 摘要 |
PROBLEM TO BE SOLVED: To provide a pencil lead which has sufficient wearability and a large concentration, maintains a practical breaking strength, and has a black color different from the light-reflecting lead color of a line written with a conventional lead containing graphite as an extender. SOLUTION: This pencil lead prepared by kneading compounding materials using at least a binder and an extender as main materials, extruding the kneaded product in a thin line-like shape, and then calcining the extruded product is characterized by containing platy alumina as the extender. COPYRIGHT: (C)2004,JPO&NCIPI
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