Silicone surfactants for use in inert gas blown polyurethane foams
CA 2204026 C · Owner: Osi Specialties, Inc. · Inventors: Miller, Glenn A.; Gerkin, Richard M.; Lawler, Lee F.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
It has now been found that the use of inert gases as an auxiliary blowing agent in flexible polyurethane foams places unexpected requirements on the composition of the silicone surfactants used in such foams. Typical silicone polyalkylene oxide polyether copolymer comb-type surfactants containing greater than about 37 % ethylene oxide in the pendant polyether chains cause large cells when added inert gas is used as the blowing agent.
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 September 11, 1996 and granted August 12, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended September 11, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 11, 2018.
- 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.