| 摘要 |
This invention provides low dust low density gypsum wallboard products ha ving high total core void volumes, corresponding to low densities in the ran ge of about 10 to 30 pcf. The wallboards have a set gypsum core formed betwe en two substantially parallel cover sheets, the set gypsum core preferably h aving a total void volume from about 80% to about 92%, and made from a slurr y including stucco, pregelatinized starch, and a naphthalenesulfonate disper sant. The combination of the pregelatinized starch and the naphthalenesulfon ate dispersant also provides a glue-like effect in binding the set gypsum cr ystals together. The wallboard formulation, along with small air bubble void s (and water voids) provides dust control during cutting, sawing, routing, s napping, nailing or screwing down, or drilling of the gypsum-containing prod ucts. This invention also provides a method of making the low dust low densi ty gypsum products including the introduction of soap foam in an amount suff icient to form a total void volume, including air voids, preferably from abo ut 80% to about 92% in the set gypsum core, corresponding to a set gypsum co re density from about 10 pcf to about 30 pcf. The wallboards produced by the method generate significantly less dust during working. |
