摘要 |
<p>A paper-covered gypsum core wallboard made of a cover paper having on the inner surface a synthetic size of the class consisting of certain substituted succinic acid anhydrides, certain substituted glutaric acid anhydrides and the reaction product of maleic anhydride and an internal olefin, which reduces the absorption by the paper of components of the wet gypsum slurry, without affecting substantially the paper porosity, and, of prime importance, without any deleterious effect on the bond of the paper to the gypsum core, either prior to the drying of the board or after the drying of the board.</p> |