Melamine-based light stabilizers for plastics
CA 2005233 C · Owner: Stephen, John Fergus · Inventors: Nelson, Richard Victor; Stephen, John Fergus
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Melamine-based compounds having a multiplicity of 2,2,6,6-tetraalkyl piperidine moieties are useful as light stabilizers for organic polymers. The compounds have the formula: (see fig. I), wherein:, R is the group: (see fig. II), R1 is selected from hydrogen and an alkyl group having 1-5 carbon atoms, R2 is selected from the group consisting of hydrogen oxyl, hydroxyl, a straight or branched chain methylene-linked alkyl group having 1-18 carbon atoms, an alkanoyl group having 2-18 carbon atoms, an alkenyl group having 3-4 carbon atoms an, alkenoyl group having 3-6 carbon atoms an alkynyl group having, 3-6 carbon atoms a cyanomethyl group, a 2,3-epoxypropyl group a, benzyl or alkylbenzyl …
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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 December 12, 1989 and granted April 13, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 12, 2009.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 12, 2011.
- 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.