Abstract: A moisture-tolerant structural panel comprising a gypsum board comprising a set gypsum core sandwiched between and faced with mats of glass fibers, wherein a free surface of one of said mats is coated with a combination of a mineral pigment, an inorganic adhesive binder and a polymer latex adhesive binder applied to said surface as an aqueous coating composition, said aqueous coating composition upon drying and setting, covering said mat to the extent that substantially none of the fibers of said mat protrude from said coating.

Abstract: A fibrous mat faced gypsum panel having on at least one of the facing sheets a moisture resistant, cured coating of a radiation curable, e.g., UV curable, polymer.

Abstract: A moisture-tolerant structural panel comprising a gypsum board comprising a set gypsum core sandwiched between and faced with mats of glass fibers, wherein a free surface of one of said mats is coated with a combination of a mineral pigment, an inorganic adhesive binder and a polymer latex adhesive binder applied to said surface as an aqueous coating composition, said aqueous coating composition upon drying and setting, covering said mat to the extent that substantially none of the fibers of said mat protrude from said coating.

Abstract: Paper and/or mat-faced gypsum board is prepared by applying a relatively thin coating of aqueous gypsum slurry containing a polyvinyl alcohol binder to one or two facer sheets. The polyvinyl alcohol binder provides adequate adhesion between the set gypsum core and the adjacent facer sheet(s) without the need for starch or other conventional binders. In one embodiment, polyvinyl alcohol is concentrated in one or more regions of the core adjacent to the facer sheet(s). In another embodiment, polyvinyl alcohol is applied to an aqueous gypsum slurry used to form the bulk core, such that the polyvinyl alcohol is present throughout the core.

Abstract: Paper and/or mat-faced gypsum board is prepared by applying a relatively thin coating of aqueous gypsum slurry containing a polyvinyl alcohol binder to one or two facer sheets. The polyvinyl alcohol binder provides adequate adhesion between the set gypsum core and the adjacent facer sheet(s) without the need for starch or other conventional binders. In one embodiment, polyvinyl alcohol is concentrated in one or more regions of the core adjacent to the facer sheet(s). In another embodiment, polyvinyl alcohol is applied to an aqueous gypsum slurry used to form the bulk core, such that the polyvinyl alcohol is present throughout the core.

Abstract: Structural components for a fire door comprising a core and edge banding and other structural components, the components comprising gypsum, expanded perlite, and cement, and having a density between about 60 and 80 lbs./ft.3. Also, a method by which the structural components are made and a fire door comprising the components.

Abstract: The present invention describes improved fire door cores and improved methods of making these fire door cores. The fire door core of the present invention comprises expanded perlite, a fireproof binder, fire clay or vermiculite, and optionally one or more viscosity-enhancing components, fiberglass, or both. The method of making this improved fire door core is a semi-continuous batch press method wherein the expanded perlite, an fireproof binder, fire clay or vermiculite are mixed; the mixture compressed in a mold, and the compressed mixture dried.

Abstract: Disclosed is a mat-faced gypsum board of the general type having a gypsum-based core formed from a gypsum slurry compressed through an extrusion ratio of at least about 3:1 wherein the fibrous mat facing on at least one side of the board has a weight per unit surface area of greater than about 1.85 lb./100 ft..sup.2 and consists essentially of inorganic fibers having a diameter of less than about 15 microns. Also disclosed are methods for manufacturing such a gypsum board and the use of such a gypsum board in exterior finishing systems, interior lath systems and as a door core.

Abstract: In a gypsum board faced with a fibrous mat, for example, a mat of glass filaments adhesively bound together, improvements are realized by the use of a reinforcing binder in the mat.

Abstract: 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.

Abstract: Fire-resistant structures are provided having at least a 20 minute ASTM E-152 fire test rating. The structures include glass partition walls having framing members formed from a gypsum-containing composition having a density of at least about 60 lbs/ft.sup.3, a flexural strength of at least 30 lbs (1/2 inch thick material), and a screw-holding capacity of at least about 400 lbs. The gypsum-containing composition further contains a substantially uniform distribution of solids including about 65 wt. % to about 90 wt. % set gypsum dihydrate, about 7 wt. % to about 30 wt. % paper fiber, and about 1.5 wt. % to about 35 wt. % of one or more performance boosters selected from inorganic fiber, clay, vermiculite, and binder polymer.

Abstract: Disclosed are fibrous mat-faced gypsum boards with improved resistance to skin irritation and itching. The boards include a mat facing in which the fibrous portion thereof comprises both inorganic and organic fibers, with organic fibers preferably being present in amount from about 5% to about 25% by weight of the total fibers.

Abstract: A fire resistant article comprising at least about 65 wt. % gypsum dihydrate, reinforcing fibers disposed substantially homogeneously throughout said set gypsum dihydrate, inorganic binder, and optionally refractive filler. This composition provides superior resistance to damage when subjected to a stream of pressurized water as from a fire hose.