PRODUCTION OF CARBONACEOUS POWDER FOR ELECTROVISCOUS FLUID

摘要

PURPOSE:To attain small initial viscosity by pulverizing a carbonaceous powder raw material by a jet pulverizer to enhance the sphericity of particles to apply the obtained carbonaceous particulate to electroviscous fluid. CONSTITUTION:The carbonaceous powder material (e.g. coal or petroleum tar, pitch and resin or the like) is heat-treated and pulverized to 0.5-40mum average particle diameter. In this case, the sphericity of the particle is heightened by using a particle collision type jet pulverizer, and the obtained carbonaceous particulate is used as a dielectric particle and is dispersed into an oily medium excellent in electrical insulation resistance to obtain the electroviscous fluid. At the time of applying voltage to the electroviscous fluid, the apparent viscosity of the fluid is rapidly and reversibly changed.