Isocyanate compositions and process for making flexible foams therefrom
CA 2014507 C · Owner: Watts, Arun · Inventors: De Witte, Mireille; Pham, Tu; Verhelst, Gabriel
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention relates to a liquid isocyanate-containing prepolymer composition having an average isocyanate functionality greater than 2 and an NCO content of from 2 to 15 % by weight, as obtainable by reacting an isocyanate reactive polymer having an average nominal functionality of from 2 to 6 with a stoichiometric excess of a diphenylmethane diisocyanate composition containing at least 2 % by weight of 2,4'-diphenylmethane diisocyanate and having an average isocyanate functionality in the range from 2 to 2.3. The invention also relates to a method for preparing a polyurethane foam, which comprises reacting such a prepolymer composition with water.
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 April 12, 1990 and granted November 14, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 12, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 12, 2012.
- 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.