Composite sheet made from mechanically delaminated vermiculite
AssigneeHercules Incorporated
InventorsHerbert T. Conner, David H. Dumas
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Abstract
Disclosed is a process for making a composite sheet using papermaking techniques. The composite sheet comprises (1) 20% to 99%, based on the weight of solids, of vermiculite delaminated by mechanical shearing only, (2) 1% to 80%, based on the weight of solids, of at least one fibrous material and (3) 0.1% to 10%, based on the weight of the vermiculite, of at least one flocculating agent.
Claims15
A composite sheet comprising (1) from about 20% to about 99%, based on the weight of solids, of vermiculite delaminated by mechanical shearing onlyand having a particle size of less than 200 microns, (2) from about 1% to about 80%, based on the weight of solids, of at least one fibrous material and (3) from about 0.1% to about 10%, based on the weight of the vermiculite, of a combination of a cationic and an anionic flocculant.
A process for preparing a composite sheet comprising the steps of:
- (a) delaminating vermiculite by mechanical shearing only by subjecting an aqueous slurry of the ore to a shearing action until a dispersion containing vermiculite lamellae having dimensions less than 200 microns is produced,
- (b) dispersing in water from about 20% to about 99% of the mechanically delaminated vermiculite and from about 1% to about 80%, based on the weight of solids, of at least one fibrous material,
- (c) adding from about 0.1% to about 10%, based on the weight of the vermiculite, of at least one flocculating agent to flocculate the dispersion, and
- (d) dewatering the flocculated dispersion to form a sheet.
Dependencies are inferred from the claim text.