Method for extending the pot-life of polyol/polyisocyanate mixtures
CA 2076185 C · Owner: Yokoyama, Thomas W. · Inventors: Yokoyama, Thomas W.; Babjak, John R.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method for extending the pot-life of a curable composition comprising a mixture of at least one active hydrogen-containing material, such as a polyol or polyamine and a , poly-isocyanate, which method comprises incorporating within the mixture a pot-life extending amount of an anhydride-functional polymer having an average of at least two anhydride groups per molecule.
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 August 14, 1992 and granted January 4, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 14, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 14, 2014.
- 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.