Method for producing high opacifying kaolin pigment
CA 2097328 A1 · Owner: Archer, Dona L. · Inventors: Turner, Ralph E. Jr.; Smith, William B.; Suitch, Paul
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method of producing a high opacifying kaolin pigment by separating from one or more iron-stained titania-containing crude kaolins having a titania content of from about 1 to 2 weight percent one or more titania-enriched kaolin fractions which contain the titania in an amount of above 2 weight percent; subjecting the fraction(s) to media grinding; dewatering and drying the media ground fraction(s); blending the fraction(s) with a fine particle size unground kaolin having a titania content less than 2 % in, proportions to provide a calciner feed having at least 2 % titania; and calcining the feed at a temperature in the range of 1500· to 2200 ·F.
Read the whole patent
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 November 26, 1991. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended November 26, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 26, 2013.
- 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.