| 摘要 |
PURPOSE:To stably obtain high-quality carbonaceous powder for an electroviscous fluid without any rise in current value in applying a voltage by heat-treating tar, pitch, a resin, etc., regulating a value of carbonization ratio, then suppressing an increase in oxygen content of the resultant product to a specific value or below, pulverizing the prepared product and classifying the powder. CONSTITUTION:An organic compound such as coal-based tar, coal-based pitch, petroleum-based tar, petroleum-based pitch, a resin and a polymer of a condensed aromatic compound is heat-treated to regulate a value of carbonization ratio (C/H) which is the ratio of the number of carbon atoms to that of hydrogen atoms within the range of 2.00 to 3.50. The resultant substance obtained by the heat treatment is then pulverized and classified by suppressing an increase in oxygen content to <=0.5wt.% in an atmosphere at <=10wt.% oxygen concentration and <=0.1wt.% moisture concentration. Thereby, the average particle diameter is regulated to 0.5-40mum to afford the objective carbonaceous powder for an electroviscous fluid providing the high-quality electroviscous fluid capable of suppressing the rise in current value in applying a voltage to the electroviscous fluid. |
