The author has studied the effects on stuffs of various reagents and of the preliminary treatments when beaten under definite conditions in the ball mill, and has obtained the following results :
1. When treated preliminary with dilute solutions of strong acids under proper conditions the wet beating of certain pulps is rapidly attained due to a reduction of the aggregation degree of the cellulose. But the loss of minute fibres or the so-called slime from the wire cloth increases and, moreover, the strength of paper sheets from them is greatly reduced. Using dilute acid solutions as beating media, no difference is found in the beating degree comparing with the case of pure water.
2. Weakly xanthated pulps give very wet stuffs by beating but the latters become very free when decomposed with an acid. The pulps once weakly xanthated and then decomposed with an acid are hard to be wet beaten.
3. The addition of alcohol or glycerin to the water retards beating.
4. The pulps treated preliminary with conc. zinc chloride solutions give very free stuffs the absorbent power of the sheets produced being very great.
5. Beating in alkaline solutions results also free stuffs. The pulps treated preliminary with conc. alkaline solutions are hard to be wet beaten.
6. Kraft pulps, when bleached, become soft and are easy to be wet beaten. The effects of breaching on sulphite pulps are not definite depending on the degree of bleaching.
7. The addition of lactic acid to the water or the preliminary steeping of pulps in dilute lactic acid solutions does not accelerate beating which being against the claim in C.G. Schwalbe's D.R.P. 379996.
8. Pulps for artificial silk show no special properties compared with ordinary paper pulps in their beating behaviours. Purified pulps for nitrocellulose are hard to be wet beaten.
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