The middle part of Figure 6 and the bottom part of Figure 7 show the trends of basis weight in the absolute dry (bone-dry) condition. It is clear that the control state was significantly stabilized by the improvement measures. The fluctuation range ±0.5 g/m2 before the improvement (*1 in Figure 6 ) has decreased to ±0.3 g/m2 (*2 in Figure 7 ), indicating that a 40% improvement effect was achieved