| 摘要 |
PURPOSE:To obtain a lead for a load, containing carbon and boron nitride as main materials, having a specific peak to X-ray irradiation perpendicular to the extrusion axis direction, usable by mounting on a plotter for writing under the low load and giving clear scripts having improved erasability. CONSTITUTION:A lead obtained by blending (A) carbon as a binder, e.g. carbon prepared by calcining a carbonizable organic compound such as natural resin, etc., and (B) boron nitride as a lubricant as main materials and molding the resultant blend to give >=40 ratio of the peak height of (002) plane of hexagonal boron nitride to the peak height of (100) plane in an X-ray diffraction obtained by irradiating X-rays perpendicularly to the extrusion axis direction of the lead. 50-300pts.wt. component (B) is preferably blended with 100pts.wt. carbonizable organic compound. |
