Water-based polyurethane release coating
CA 2115002 C · Owner: Minnesota Mining And Manufacturing Company · Inventors: Sengupta, Ashok
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention relates to novel water-soluble or water-dispersible polyurethane compounds and to compositions that contain the novel compounds and are useful for instance, as low adhesion backsize for adhesive tapes. The invention also relates to processes for preparing the novel compounds compositions and tapes. The novel polyurethane compound is a water-soluble or water-dispersible polyurethane polymer whose polymer chain includes segments derived from a silicone polycarbinol and whose polymer chain is endcapped with a silane. The process is a process for preparing a water-souble or water-dispersible polyurethane polymer which process comprises:, (a) preparing an isocyanate-terminated …
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 February 4, 1994 and granted August 3, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 4, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 4, 2016.
- 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.