A method for the production of perlite microspheres of

摘要

Perlite reduced to a particle size of less than 200 mesh in a binder of aqueous sodium ligno-sulfonate is expanded while suspended in a gaseous medium in a fluidized state at temperatures ranging from 1800. degree. to 2200°F. for a period of 30 to 60 seconds. The resultant microspheres have excellent physical properties and are suited to use as fillers for resins.