Patent Intelligence / US 7,731,794 B2
US 7,731,794 B2

High starch light weight gypsum wallboard

Dispersant + starch chemistry
Assignee
United States Gypsum Co
Inventors
Qiang Yu, Weixin D. Song, Michael R. Lynn
Jurisdiction
United States (USPTO)
Filed
2006-06-07
Published
2010-06-08
Priority
2006-06-07
Abstract — verbatim from Google Patents

The invention generally provides gypsum-containing slurries including stucco, naphthalenesulfonate dispersant, and pregelatinized starch. The naphthalenesulfonate dispersant is present in an amount of about 0.1%–3.0% by weight based on the weight of dry stucco. The pregelatinized starch is present in an amount of at least about 0.5% by weight up to about 10% by weight of pregelatinized starch by weight based on the weight of dry stucco in the formulation. Other slurry additives can include trimetaphosphate salts, accelerators, binders, paper fiber, glass fiber, and other known ingredients. The invention also comprises the gypsum-containing products made with such slurries, for example, gypsum wallboard, and a method of making gypsum wallboard.

Claim 1 — verbatim

A light weight high strength, low dusting gypsum wallboard comprising: a set gypsum composition formed between two substantially parallel cover sheets, the set gypsum composition made using a gypsum-containing slurry comprising: water, stucco, pregelatinized starch, and a naphthalenesulfonate dispersant, wherein the pregelatinized starch is present in an amount from about 0.5% by weight to about 10% by weight based on the weight of stucco.

Further claims, drawings, prosecution history and legal status: see the official record.

Sources
  1. [1]US 7,731,794 B2 — High starch light weight gypsum wallboard Google Patents · 2010-06-08