摘要 |
Building panels such as ceiling tiles have compositions including starch as a binder and a coagulant for the starch. The building panels also can include a fibrous material and a filler. In one aspect, the starch is coagulated by the coagulant resulting in the starch being distributed substantially uniformly through a thickness of the building panels, whereby certain physical properties of the building panels and a wet-felting process for manufacturing the building panels are improved. The coagulant can comprise at least one aluminum salt. In the wet-felting process for manufacturing the ceiling tiles, a slurry comprising an aqueous dispersion of at least one fibrous material, at least one filler material, at least starch as a binder and a coagulant for the starch is delivered onto a foraminous wire frame. The slurry is dewatered to form a basemat and the basemat is dried to remove any residual moisture. |