Extruded fire resistant construction and building products
AssigneeArmstrong World Industries, Inc.
InventorsDebra L. Morris, Albert G. Landers
Life of this patent
Estimating the term…
Abstract
An extrudable composition is provided which is made up primarily of gypsum, a binder/rheology aid and water with a crumbly, semi-dry consistency. The extrudable composition described can be extruded through a die to provide a building product. Density can be minimized and strength optimized by using features of the composition and of the process.
Claims12
An extruded gypsum building product which comprises calcium sulfate dihydrate at an amount in the range of from about 46% up to about 85% by weight, a binder/rheology aid which is a cellulosic binder, said binder/rheology aid being present at an amount in the range of from about 0.5 to about 15% by weight, optionally perlite at an amount in the range of from about 1 to about 35% by weight, wherein said building product has a modulus of rupture of at least about 700 pounds per square inch, and wherein further, the building product was extruded with a composition having a water:calcium sulfate hemihydrate weight ratio in the range of from about 0.5 to about 0.85 and fiber for green strength at an amount in the range of from about 1 to about 20% by dry weight.
An extruded gypsum building product which comprises calcium sulfate dihydrate at an amount in the range of from about 46% up to about 85% by weight, a binder/rheology aid which is a cellulosic binder, said binder/rheology aid being present at an amount in the range of from about 0.5 to about 15% by weight, perlite at an amount in the range of from about 1 to about 35% by weight, wherein further, the building product has a modulus of rupture of at least about 700 pounds per square inch and was extruded with a composition having a water:calcium sulfate hemihydrate weight ratio in the range of from about 0.35 to about 0.5 and fiber for green strength at an amount in the range of from about 1 to about 20% by dry weight.
An extruded gypsum building product which comprises calcium sulfate dihydrate at an amount in the range of from about 46% up to about 85% by weight, methylhydroxyethylcellulose as a binder/rheology aid which is present at an amount in the range of from about 0.5 to about 15% by weight, perlite at an amount in the range of from about 1 to about 35% by weight and optionally cellulose fibers at an amount up to about 20% by weight;
- wherein further, the building product was extruded with a composition having a water:calcium sulfate hemihydrate weight ratio in the range of from about 0.35 to about 0.85, the water being present at a sufficient amount for both the rehydration of the calcium sulfate hemihydrate to calcium sulfate dihydrate and for extrusion processing, and said building product having a modulus of rupture of at least about 700 pounds per square inch.
Dependencies are inferred from the claim text.