Process for the removal of chloride ions from a fine-particle titanium dioxide, such fine-particle titanium dioxide freed from chloride ions and its use
CA 2069705 A1 · Owner: Kronos (Usa) Inc. · Inventors: Elfenthal, Lothar; Schroeder, Siegfried
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention relates to a process for the removal of chloride ions from a fine-particle titanium dioxide A titanium dioxide sol containing at least 100 g/l TiO2 is mixed at a temperature, between 40°C and the boiling point with an aqueous alkaline, solution up to a pH of between 4 0 and 11.0 while stirring without generating high shear, resulting essentially in a tangential to radial flow of the liquid; the fine-particle titanium dioxide is flocculated in this procedure, subsequently it is filtered and washed with an aqueous electrolyte solution The flocculated mixture has a low viscosity which results in short filtration and washing times and in an improved removal of chloride. The …
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 May 27, 1992. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended May 27, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 27, 2014.
- 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.