Precoated controlled release fertilizers and processes for their preparation
CA 2300259 C · Owner: Timmons, Richard J. · Inventors: Johnson, William R.; Timmons, Richard J.; Goertz, Harvey M.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A controlled release fertilizer formed from nutrient granules having intermediate or precoat layers of organic oil such as raw linseed oil, prior , to application of a polymeric encapsulating coat. The precoat may also contain a binding agent, such as a fine clay and a drier. The new fertilizer , composition is made by a process of applying the oil precoat but not curing , it until after the encapsulating coat is applied. The use of the precoat provides more desirable controlled (delayed) release characteristics at a lower weight of the encapsulating coat particularly for nutrient cores having a relatively large number of surface imperfections or discontinuities.
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 June 9, 1999 and granted December 18, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 9, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 9, 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.