Stabilized, high solids, low viscosity smectite slurries, and method of preparation
CA 2172542 C · Owner: Kemira Chemicals, Inc. · Inventors: Payton, James; Miranda, Jorge; Canaris, Nicholas
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An aqueous slurry of smectite clay of elevated solids content comprising an aqueous solution or emulsion of at least 0.2 % by weight of said slurry of a salt of a low molecular weight amine salt in which is dispersed from about 10 to 47 % by weight of the slurry of a, smectite clay. The amine salt is effective to prevent the smectite from swelling appreciably whereby the slurry can be shipped and stored without creating a gelling problem. The inhibiting or suppressing effect of the amine salt on the swelling of the clay and on gelling of the slurry is reversible upon subsequent dilution with water thereby facilitating use of the smectite in typical applications as a retention, aid in paper …
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed September 23, 1994 and granted May 29, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended September 23, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 23, 2016.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.