31
Progressive increase then decrease concept diagram
：
According to above diagram, the initial means the first sheet’s crease data.
Variable means the different between two sheet’s crease lines. For example,
sheets number is 11. 1
st
to 6
th
are progressive increase by 0.5mm; then, 7
th
to
11
th
are progressive decrease by 0.5mm.
The book after this function can be opened flatly.
However, the book without this function cannot be opened flatly.
First sheet
Sheet of decrease
Initial
Variable
Sheet of Increase