초록 ▼

A lightweight gypsum board is provided, including, by dry weight, gypsum as the largest single ingredient, perlite as the second largest single ingredient, and starch as a minor ingredient, in the board. The starch may be pre-cooked prior to mixing, and is dispersed in the core of the board to act a

A lightweight gypsum board is provided, including, by dry weight, gypsum as the largest single ingredient, perlite as the second largest single ingredient, and starch as a minor ingredient, in the board. The starch may be pre-cooked prior to mixing, and is dispersed in the core of the board to act as a binder for binding the gypsum to the perlite. Gypsum board made according to the invention is lighter in weight, yet has a comparable nail pull value to conventional wallboard.

대표청구항 ▼

[ What is claimed is:] [1.] A lightweight gypsum wallboard comprising:a core including:a. gypsum, said gypsum being the largest single ingredient, by dry weight in the core, said gypsum comprising at least 50% of the dry weight of the core;b. perlite having a bulk density of approximately 3-3.5 poun

[ What is claimed is:] [1.] A lightweight gypsum wallboard comprising:a core including:a. gypsum, said gypsum being the largest single ingredient, by dry weight in the core, said gypsum comprising at least 50% of the dry weight of the core;b. perlite having a bulk density of approximately 3-3.5 pounds per cubic foot, said perlite being the second largest single ingredient, by dry weight, in the core, said perlite comprising less than 50% of the dry weight of the core and being distributed throughout said core;c. fibers comprising in the range of 0.5% to 5.6% of the dry weight of the core;d. starch comprising in the range of 0.25% to 6% of the dry weight of the core: ande. first and second sheets of face paper, said core being surfaced by said first and second sheets;wherein the wallboard ha a density of between 21.5 and 37.1 pounds per cubic foot.