Back to results
US 5,558,710 AGranted
Gypsum/cellulosic fiber acoustical tile composition
AssigneeUSG Interiors, Inc.
InventorMirza A. Baig
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
AssigneeUSG Interiors, Inc.
InventorMirza A. Baig
Estimating the term…
An acoustical tile composition based on a gypsum/cellulosic fiber composition which can replace all or a portion of the mineral wool normally present in acoustical ceiling tiles. The gypsum/cellulosic fiber composition is combined with a lightweight aggregate material and a binder to form a composition which is used in a water-felting process to manufacture acoustical ceiling tiles and panels. The preferred source of the cellulosic fiber is a composite gypsum/cellulose fiber material which is prepared by mixing the gypsum and cellulosic fiber material with sufficient water to form a dilute slurry which is then heated under pressure to calcine the gypsum, converting it to an alpha calcium sulfate hemihydrate. The resulting composite material comprises cellulosic fibers physically interlocked with calcium sulfate crystals. Another source of both gypsum and cellulosic fibers is waste (scrap) gypsum wallboard. Expanded perlite is the preferred lightweight aggregate material.
A wetted, mineral wool-free composition suitable for making acoustical tiles in water-felting process consisting essentially of gypsum, cellulosic fiber, a lightweight aggregate material and a binder, in which on a dry solids basis there is at least about 15% by weight of gypsum and at least 13% by weight of cellulose fiber.
A wetted, mineral wool-free composition suitable for making acoustical tiles in a water-felting process consisting essentially of gypsum, cellulose fiber, a lightweight aggregate material and a binder in which at least a portion of the gypsum and the cellulosic fiber are in the form of a composite material which has been produced by calcining under pressure a dilute slurry of gypsum and cellulosic fiber.
A wetted, mineral wool-free composition suitable for making acoustical tiles in a water-felting process consisting essentially of gypsum, cellulosic fiber, a lightweight aggregate material and a binder in which on a dry solids basis there is at least 13% by weight of cellulose fiber, and a substantial portion of the gypsum and a minor portion of the cellulose fiber are in the form of ground gypsum wallboard.
A wetted composition suitable for making acoustical tiles in a water-felting process consisting essentially of mineral wool, gypsum, cellulosic fiber, a lightweight aggregate material and a binder, in which on a dry solids basis there is at least about 10% by weight of mineral wool, at least about 10% by weight of gypsum and at least 13% by weight of cellulose fiber.
A dry mineral wool-free acoustical tile made by a water-felting process consisting essentially of gypsum, cellulosic fiber, a lightweight aggregate material and a binder in which there is at least about 15% by weight of gypsum and at least 13% by weight of cellulose fiber.
A dry mineral wool-free acoustical tile made by a water-felting process consisting essentially of gypsum, cellulosic fiber, a lightweight aggregate material and a binder in which at least a portion of the gypsum and the cellulosic fiber are in the form of a composite material which has been produced by calcining under pressure a dilute slurry of gypsum and cellulosic fiber.
An acoustical tile made by a water-felting process consisting essentially of mineral wool, gypsum, cellulosic fiber, a lightweight aggregate material and a binder in which there is at least about 10% by weight of mineral wool, at least about 10% by weight of gypsum and at least 13% by weight of cellulose fiber.
Dependencies are inferred from the claim text.