CARBONACEOUS POWDER FOR ELECTROVISCOUS FLUID AND PRODUCTION THEREOF

摘要

PURPOSE:To obtain the subject powder excellent in stability for a long period and stability to temperature by specifying the value of C/H ratio within a specified range and/or the amount of weight loss within a specific temperature range in nitrogen atmosphere within a specified range. CONSTITUTION:Carbonaceous powder used as dielectric fine particles in an electroviscous fluid obtained by dispersing the dielectric fine particles in an oily medium excellent in electrical insulating properties. The aforementioned powder is provided so as to satisfy at least one condition of the following. The value of the ratio (C/H) between the numbers of carbon atoms to hydrogen atoms within the range of 1.70-3.50 and the amount of weight loss at a temperature within the range of 400-600 deg.C in nitrogen atmosphere within the range of 0.5-13.0wt.%. Thereby, the objective carbon powder excellent in stability for a long period and stability to temperature for an electroviscous fluid is obtained.