| In this paper, the different effects of calcium-ions and sodium-ions on wet end performance and properties of hand-sheets were investigated. The results showed that metal ions could enhance the retention and drainage ability of the pulp without any chemical aids. However when chemical aids such as cationic starch, AKD, CPAM, silica sol were added into the pulp, metal ions impaired the ability of the chemical aids and affected the retention and drainage ability of the furnish, the reduction of retention and drainage ability of the furnish caused by calcium-ions was more significant than sodium-ions. Metal ions also affected the sizing efficiency of AKD, the reducing effect of calcium-ion was stronger than sodium-ions. On the other hand increasing the metal ions content in the furnish, tensile index and folding endurance of the hand-sheets increased at first and then decreased, sodium-ions was superior to calcium-ions in hand-sheets strength when the conductivities of the furnish were the same. |
