초록 ▼

Fiberboards are provided containing at least about 65 wt. % calcium sulfate dihydrate derived from hemihydrate or anhydrous gypsum, and at least about 7 wt. % pulped paper fibers. The boards are capable of being formed into structural members having superior mechanical properties and/or fire resista

Fiberboards are provided containing at least about 65 wt. % calcium sulfate dihydrate derived from hemihydrate or anhydrous gypsum, and at least about 7 wt. % pulped paper fibers. The boards are capable of being formed into structural members having superior mechanical properties and/or fire resistance, including screw-holding capacities in excess of 650 lbs.

대표청구항 ▼

[ What is claimed is:] [1.] A fiberboard comprising from about 65 wt. % to about 90 wt. % set gypsum derived substantially from non-fibrous gypsum hemihydrate, from about 7 wt. % to about 30 wt. % homogeneously distributed pulped paper fiber, and from about 1.5 wt. % to about 7 wt. % of inorganic fi

[ What is claimed is:] [1.] A fiberboard comprising from about 65 wt. % to about 90 wt. % set gypsum derived substantially from non-fibrous gypsum hemihydrate, from about 7 wt. % to about 30 wt. % homogeneously distributed pulped paper fiber, and from about 1.5 wt. % to about 7 wt. % of inorganic fiber consisting essentially of siliceous fiber, and from about 1.5% to about 7 wt % clay, said fiberboard having a density of at least about 60 lbs./cu. ft. and a screw-holding capacity of at least about 400 lbs.