Standard for font size requirements of ancient books binding

The national standard font requires the font size to be equal to the height of the font, that is, the No.5 font size is equal to the height of 5㎜, and the font size is set to 5.

Then the font number 5 of Songti is 10.5. Songti is a Chinese font that seems to be suitable for printing, and the strokes are different in thickness.

Moreover, it is generally thin and thick, and is often used for text typesetting of books, magazines and newspapers.