Process for preparing colloidal calcium carbonate by particle size
CA 2196124 C · Owner: You, Kyu Jae · Inventors: You, Kyu Jae
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention provides a process for the preparation of a colloidal calcium carbonate of which the particles have a specific size in the range of more than 0.04 µm to less than 0.08 µm, which has little affinity of aggregation and has properties suitable for specific uses. First, after adding an additive for example, sugar to, increase a concentration of calcium ion to an aqueous lime suspension, by, introducing a gas containing carbon dioxide thereinto a colloidal calcium, carbonate of 0.04 µm in particle size is obtained. And then by adding a hydroxide with univalent or bivalent cation to the above aqueous suspension and agitating it at the rate of 100 to 5,000 as Reynolds number while …
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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 January 28, 1997 and granted December 19, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 28, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 28, 2019.
- 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.