-It is a product that retains the conventional "hard to break", "dark" and "smooth" features, but adds a "hard to get dirty" function.
-Even if you draw a marker such as a highlighter pen, the spread of the core powder is suppressed, so the characters do not easily bleed and the paper surface is not soiled.
-The dirt caused by the core powder adhering to the pen tip of the marker is also reduced, and the notebook can be kept clean.