Process for preparing water resistant luminous pigments
CA 2290340 C · Owner: Nemoto & Co. Ltd. · Inventors: Kitagawa, Yosuke; Hoshikawa, Ryuichi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for preparing a water resistant luminous pigment with durability, characterized in that a luminous pigment in, which an oxide matrix comprising at least one element selected from the group consisting of Mg, Ca, Sr Ba and Zn and at least, one element selected from the group consisting of B A1, P and, Ga is doped with at least one rare-earth metal element is subjected, to an acid treatment under the condition of pH of not more than 3 using at least one acidic compound selected from the group consisting of acids and acid generating compounds and is, subsequently subjected to an alkaline treatment under the condition of pH 4-9 using at least one alkaline compound selected from 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 October 7, 1999 and granted September 9, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 7, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 7, 2021.
- 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.