Process for preparing granular urea
CA 2215596 C · Owner: Toyo Engineering Corporation · Inventors: Morikawa, Haruyuki; Fujii, Hidetsugu
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention provides a process for preparing granular urea which , solves a problem for removing a moisture in a prilling tower method and a problem for concentrating diluted formaldehyde in granulation by a fluidized, spouted bed method when urea is granulated in the presence of formaldehyde. That is the present invention , provides a process for preparing granular urea from liquid drops or sprayed drops of a urea solution, wherein the urea solution is divided into two portions of a urea solution A and a urea solution B and a, urea solution prepared by mixing an aqueous formaldehyde solution with the urea solution A, concentrating the above mixed solution and then mixing it …
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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 21, 1997 and granted October 16, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 21, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 21, 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
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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.