Alkaline soaking after ozone treatment was studied for mechanical pulp in order to improve sheet strengths of ozone treated pulp with yield of 85% or more.
The results obtained are summarized as follows :
Alkaline soaking of ozone treated pulp increased tear factor and breaking strengthe to 1.2 and 1.5 times higher respectively than those of non-soaked pulp.
Alkaline soaking reduced brightness, freeness and slightly pentosan content in the pulp. On the other hand, it increased sheet density, K value and carboxyl group content.