Cementitious gypsum-containing compositions and materials made therefrom
CA 2191842 C · Owner: National Gypsum Company · Inventors: Finkelstein, Ronald S.; Burkard, Edward A.; Stav, Elisha
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A cementitious composition useful for water-resistant construction materials including floor underlayments, backing boards self-leveling floor materials, road patching materials fiberboard, fire-proofing sprays, and fire-stopping materials includes about 30 wt.% to about 75 wt.% calcium sulfate betahemihydrate, about 10 wt.% to about 40 wt.% Portland cement about 4 wt.% to , about 20 wt.% silica fume and about 1 wt.% to about 40 wt.% pozzolanic filler.
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 May 24, 1995 and granted August 7, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 24, 2015.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 24, 2017.
- 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.