| abstract |
PURPOSE: To obtain composite particles showing good casting physical properties and high bulk density by dispersing filler particles in a specific polyimide soln. and introducing this dispersion into an aq. dispersant to coat the filler particles with a polyimide layer. n CONSTITUTION: Filler particles composed of graphite, glass, MOS 2 mica or polytetrafluoroethylene, etc., are dispersed in a soln. of a polylmide having a polyimide structure unit represented by formula (wherein R is 2,4-toluene, 2,6-toluene or a group represented by formula II) to obtain a dispersion. This dispersion is introduced into an aq. dispersant to coat at least a part of the filler particles to obtain the objective particles pref. having the max. particle size of 3 mm and bulk density of 0.20-0.70 g/cm 3 . n COPYRIGHT: (C)1991,JPO |