Method for production of high solid aqueous calcium carbonate suspensions
AssigneeECC International Limited
InventorsAlan J. Brown, Michael S. Darsillo, O. Wayne Bentley, Jr.
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Abstract
A method for producing a high solids aqueous slurry of particulate calcium carbonate having highly stable aging characteristics, comprising dispersing in water at at least 70% by weight solids, a finely divided particulate calcium carbonate, utilizing as a dispersing agent from 20 to 34 lbs/ton of dry mineral (expressed as 40% actives), of a copolymer of acrylic acid and a sulfonated vinyl monomer, which is converted to the salt form by from about 30 to 50% of its carboxylic acid sites being neutralized with a polyvalent cation, and substantially the balance of said carboxylic sites being neutralized with a monovalent cation.
Claims7
A method for producing a high solids aqueous slurry of particulate calcium carbonate having highly stable aging characteristics, comprising:
- dispersing in water at least 70% by weight solids of a finely divided particulate calcium carbonate in water, from 20 to 34 lbs (expressed on the basis of 40% actives) per ton of dry carbonate, of a salt form of a copolymer of acrylic acid and sulfonated vinyl monomer, having from about 30 to 50% of its carboxylic acid sites neutralized with a polyvalent cation, and substantially the balance of said carboxylic acid sites neutralized with a monovalent cation;
- wherein said copolymer is a polymerization product of from 1 to 75% by weight AMPS and 99 to 25% by weight of acrylic acid and having a molecular weight in the range of from about 1,000 to 20,000;
- and, wherein said polyvalent cation is selected from the group consisting of calcium, aluminum and magnesium.
Dependencies are inferred from the claim text.