Hard-edge wallboard

摘要

A method of making gypsum wallboard in which a portion of the conventional foamed gypsum slurry for forming the wallboard core is fed through a relatively low speed agitator wherein a defoaming agent is thoroughly admixed therewith, and this portion of the slurry is then disposed along the edge portion of the wallboard being formed, whereby a hard-edge wallboard is produced using less energy than used with prior methods for making a hard-edge wallboard.