Method of producing gypsum/fiber board, especially for floor boards
CA 2038147 C · Owner: Pro Mineral Gesellschaft Zur Verwendung Von Mineralstoffen Mbh · Inventors: Koslowski, Thomas
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Gypsum/fiber board especially for use as floor board, is, fabricated by preparing a binder consisting of at least 60% by weight of calcium sulfate alpha hemihydrate and at most 35% by, weight calcium sulfate beta hemihydrate the balance, if any, inert, material such as grinding residues from finished plaster board in, an amount of 100 parts by weight of the binder to 20 parts by weight of fiber, especially cellulose fiber or a mixture of cellulose fiber from scrap paper with reinforcing fiber. This dry mixture is combined with water in an amount such that no water can be expressed from the prepared mix by the subsequent pressing step and the prepared mix is then pressed in a …
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 March 13, 1991 and granted October 18, 1994. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 13, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 13, 2013.
- 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.