PURPOSE: To obtain pulverized pulp of a desired particle size in an industrially advantageous manner under mild conditions without causing decomposition and degradation of cellulose, by pulverizing pulp after being dried and cooled to a specified temperature.
CONSTITUTION: Pulp dried to a moisture content of below 1.0% is pulverized at a temperature within the range of about -30W0°C while the pulp is being maintained at a moisture content of below 1.0%. This dehydration may produce not only an effect of heightening the density of pulp but also such an effect that the pulp sheet loses its flexibility and stiffens and at the same time the cellulose fiber deprived of water gets very prominent thermoplasticity. The drying condition should be within such a limit as not to cause the thermal decomposition or oxidative degradation of cellulose but to cause its dehydration or and the cleavage of its hydrogen bonds because if the heat drying is carried out to such a degree that the thermal decomposition or oxidative decomposition occurs, problems such as loss of whiteness and quality degradation arise. In order to perform this dehydration remarkably effectively and to heighten the pulverization effect further, it is preferred to use pulp of an extraction pH in the range of 2W5.
KAIDA SATSUKO
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