Moisture resistant polyurethanes derived from non- aromatic diisocyanates
CA 1262991 C · Owner: Lee, Chi-Long · Inventors: Lee, Chi-Long; Gornowicz, Gerald A.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The reduction in tensile strength exhibited in high humidity environments by "soft" polyurethanes prepared from aliphatic or cycloaliphatic diisocyanates can be substantially reduced if the molar ratio of diisocyanate and chain extender to isocyanate-reactive species other than said chain extender in the reaction mixtures from which said polyurethanes are prepared is at least 4.
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
- Granted November 14, 1989. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended November 14, 2006.
- 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.