Composite fiberboard and process of manufacture
CA 2003204 C · Owner: Awi Licensing Company, Inc. · Inventors: Kehrer, Kenneth P.; Felegi, John, Jr.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A novel composite board of mineral wool perlite, and cellulosic newsprint fibers for use primarily as a ceiling tile is disclosed. The board displays virtually no sag (less than 200 mils) when exposed to high temperature and high humidity while displaying quite acceptable strength. The board is manufactured by selective deposition of a latex composition on the cellulosic newsprint fibers.
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 November 17, 1989 and granted December 22, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 17, 2009.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 17, 2011.
- 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.