| 摘要 |
PURPOSE:To produce an inorg. filler having no acute angles and improving the flowability and moldability of its resin compound by heat treating a pulverized product of molten silica under special conditions. CONSTITUTION:Natural silica, rock crystal or synthesized silica powder is melted until the crystal content is reduced to <=0.2%. The resulting molten silica is pulverized to <=149mum max. particle size and the pulverized product is passed through a flame kept at a temp. above the m.p. of silica at a concn. of 6-20kg powder in the flame per 1Nm<3> combustible gas to obtain an inorg. filler made of siliceous powder having <=149mum max. particle size, 1-50mum average particle size, <=10m<2>/g specific surface area and <=0.2% crystal content. The inorg. filler has no acute angles.
|
