Effects of di-valent cations on dielectric properties of un-impregnated paper were studied in the same method as that of part I.
(1) If Ba⁺⁺ was expected, di-valent cations did not influence more badly on the dielectric loss at high temperature than mono-valent cations, Na⁺ and K⁺ etc.
(2) The dieletric loss at high temperature of un-impregnated paper was improved without washing with water after immersed in the aqueous solution of di-valent cations.
(3) On the effects of di-valent cations on the dielectric properties, it was cleared that Pb⁺⁺ and Fe⁺⁺ were much better and Ba⁺⁺ was the worst.

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Part.1. On the Filterability of Viscose.
In order to investigate the relation between the conditions of hot alkali purification and the reactivity of pulp in viscose process, a group of pulps (α-cellulose 89, 90, 92, 94 and 95%) are prepared by controlling the hot alkali purification conditions in the five stage bleaching (Cl₂-NaOH-Cl₂-NaOH-NaOCl).
From the viscose tests of these pulps, the following results are obtained :
The values of cellulose yield in mercerization of pulp depend on the hot alkali purification conditions.
But the relation between α-cellulose and the filterability of viscose is not clear.
It is observed slightly the KW of (90 and 92% α-pulp) are better than the other, and reproductivity of KW of 89% is worse than the other.
Part.2. On the Aging of Alkali Cellulose.
To clear the influence of hot alkali purification on the reactivity of pulp in viscose process, the group of pulps (shown in Part. 1.) are mercerized with 17.5% NaOH solution and aged later . By this alkali aging process, the following results are obtained :
1. The depolynierization velocities during aging are nearly the same and does not depend on the α-cellulose content.
2. Though the effects of the hot alkali purification conditions on the content of hemicellulose, distribution of polymerization degree and reactivity by emulsion xanthation method (M . W. and S.W.) of pulp are greatly decreased during alkali aging process, their effects still remains in these fields after aging.
3. The relation curves between filterability and sulfonation time of diluted viscose solution depend on the purification of the pulp.

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