Treatment of fibrous material
CA 1061237 A · Owner: Karl Kroyer St. Anne'S Limited · Inventors: Attwood, Brian W.; Hicklin, Denis R.; White, Derek G.W.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
In a process for making a multi-ply consolidated dry-formed fibrous web having at least three plies the outer plies are impregnated, with a stiffening agent (e.g. starch) and the intermediate plies are impregnated with a sizing agent (e.g. wax/rosin size) to render them impervious to the stiffening agent. After the web has been consolidated by hot moist pressing, its outer surfaces may be further sized and hot moulded.
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 August 28, 1979. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended August 28, 1996.
- 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.