| 摘要 |
PROBLEM TO BE SOLVED: To provide a pencil lead which can write densely on a smooth paper surface such as coat paper, moisture absorption is prevented, has good erasability and lead retentiveness, and is suitable for pencil lead in wood shaft and for mechanical pencil lead.SOLUTION: A pencil lead contains at least one kind selected from acetylenic glycols, their alkylene oxide additions and acetylene alcohols as an impregnate component or a surface treatment component of a sintered pencil lead body.SELECTED DRAWING: None |
