摘要 |
Thermal and/or acoustic insulation materials based on dried precipitated silica, having a total pore volume of from 1 to 5 cm3/g and optionally containing reinforcing fillers and/or opacifying agents, are prepared by: (A) filtering an aqueous dispersion D containing precipitated silica particles in a filter press, whereby a compacted filter cake is obtained; and then (B) drying the filter cake in the compacted state as obtained after step (A). |