Rock wool composite material

摘要

A rock wool composite material obtained by mixing a fine rock wool having a diameter of 1 to 10 mu and a length of 70 to 500 mu and containing substantially no shots with a pulp-like substance of a heat-resistant aromatic polymer having a freeness value of 150 seconds or more and less than 500 seconds, is excellent in heat resistance, incombustibility, heat insulation and electrical insulation and is advantageously used as a substitute for an asbestos sheet or board.