Pour-in-place flexible polyurethane foam articles
CA 2074761 C · Owner: Gill, William A. · Inventors: Gill, William A.; Leung, Siusun Kenneth
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
It has been discovered that a particular polyurethane formulation may be used to prepare "pour-in-place" (PIP) polyurethane foam articles where the formulation is injected into a mold bearing an exterior covering such as a fabric without the foaming liquid striking through the layer. The formulation employs a hydrophilic polyhydric compound to help the reactivity balance that minimizes penetration of the exterior covering while also stabilizing the rising foam against shear collapse without excessively tightening the foam. Contrary to the conventional expectation that the hydrophilic polyhydric compound would, cause strike through problems since it delays the initial reaction time, it has …
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 July 28, 1992 and granted September 21, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 28, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 28, 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.