Abstract: A joint compound system includes a set-inhibited, pre-wetted, setting-type, ready-mix joint compound and a set initiator. The set-inhibited, pre-wetted, setting-type joint compound includes a ready-mixed, setting-type joint compound base with a calcium-free phosphate set preventing agent that impedes chemical hydration of a gypsum component of the setting-type joint compound. The joint compound base is free of calcium carbonate. The set initiator includes alum to reinitiate the chemical hydration reactions.
Abstract: I provide a multi-part aqueous gypsum dental casting composition having gypsum and water and wherein (a) one or more of a first compound is mixed in the gypsum and/or water; or (b) one or more of the first compound and one or more of a second compound are mixed in the gypsum and/or water; or (c) one or more of the first compound and one or more of an acid are mixed in the gypsum and/or water; or (d) one or more of the first compound and one or more of the second compound and one or more of the acid are mixed in the gypsum and/or water; or (e) two or more of the acids and optionally one or more of the second compound are mixed in the gypsum and/or water; and (f) the gypsum and water are maintained separately and mixed when the casting is to be prepared. Also provided are the dosage sized containers for the above, along with the dosage size containers having gypsum enhancers.
Abstract: Methods and compositions for sealing subterranean zones penetrated by well bores are provided. The methods basically comprise the steps of introducing a sealing composition into the subterranean zone comprised of a hydraulic cement, sufficient water to form a slurry and a rapidly acting thixotropy providing gelling agent, and allowing the sealing composition to remain at rest in the zone whereby the sealing composition rapidly gels and then sets into a hard impermeable mass therein.
Abstract: I provide a multi-part aqueous gypsum dental casting composition having gypsum and water and wherein (a) one or more of a first compound is mixed in the gypsum and/or water; or (b) one or more of the first compound and one or more of a second compound are mixed in the gypsum and/or water; or (c) one or more of the first compound and one or more of an acid are mixed in the gypsum and/or water; or (d) one or more of the first compound and one or more of the second compound and one or more of the acid are mixed in the gypsum and/or water; or (e) two or more of the acids and optionally one or more of the second compound are mixed in the gypsum and/or water; and (f) the gypsum and water are maintained separately and mixed when the casting is to be prepared. Also provided are the dosage sized containers for the above, along with the dosage size containers having gypsum enhancers.
Abstract: A multipart gypsum casting composition comprising a gypsum composition and a water composition where either the water and/or the gypsum composition contains at least two acids selected from the group consisting of oxalic acid, boric acid, phosphoric acid, citric acid, sodium citric acid, trisodium citric acid, tartaric acid, sulfuric acid, acetic acid, formic acid, malic acid, ascorbic acid and aspartic acid.
Abstract: A method of preparation of gypsum wallboard, as well as a core composition suitable for use therein, are disclosed. The core composition includes a slurry of calcium sulfate hemihydrate (stucco), water, and calcium aluminum lignosulfonate and/or aluminum lignosulfonate.
Type:
Grant
Filed:
August 21, 1998
Date of Patent:
March 9, 1999
Assignee:
National Gypsum Company
Inventors:
Jashbhai M. Patel, Ronald S. Finkelstein
Abstract: A cement composition consists essentially of (a) from 50% to 97% by weight (calculated on the total composition) of a Portland cement clinker, the sulfur content of which is from 0.5% to 10% by weight expressed as SO.sub.3 and the fluorine content of which is from 0.13% to 1.00% by weight expressed as F, and (b) from 3% to 50% by weight (calculated on the total composition) of an extender containing a carbonate selected from calcium carbonate, magnesium carbonate, calcium magnesium carbonate and mixtures thereof as its main constituent and having a median particle size (d.sub.50) of below 14 .mu.m. Preferably, the total content of C.sub.3 S and C.sub.2 S in the Portland cement clinker is at least 65%. A preferred carbonate is electrostatic precipitator dust extracted from cement kiln exhaust gases. The cement composition may be mixed with further components such as other extenders, retarding agents and aggregate.
Abstract: Blocks, weighing about 35 lbs., formed of a homogeneous mixture of about 75% gypsum and 25% lime, are strategically placed in surface water that is being damaged by acid rain, where, by timed release of lime, the pH of the water is maintained at about 6.5 pH.