Rare-earth and alkali sulphide, method for preparing same and use thereof as a pigment
CA 2230716 C · Owner: Macaudiere, Pierre · Inventors: Macaudiere, Pierre; Aubert, Maryline
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A rare-earth and alkali sulphide, a method for preparing same and the use thereof as a pigment are disclosed. The sulphide has formula ABS¿2? wherein A is at least one alkali and B is at least one rare earth and consists of grains having an average size no greater than 1.5 µm. The method for preparing said sulphide comprises exposing at least one rare-earth carbonate or hydroxycarbonate to at least one alkaline element compound then heating them in the presence of at least one gas selected from hydrogen sulphide or carbon sulphide and optionally deagglomerating the resulting material. The sulphide may be used as a pigment in plastics paints, surface coatings, rubbers, ceramics glazes, …
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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 13, 1996 and granted August 6, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended September 13, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 13, 2018.
- 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.