Expired Canadian patentCanada
Foamed and solid rubber-graft copolymer compositions and method of preparation
CA 1089575 A · Owner: Maher, George G. · Inventors: Maher, George G.
Overview
Drawings and full text
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Starch graft polymers prepared by reacting a water soluble starch xanthate with hydrogen peroxide and vinyl monomer. The vinyl monomer has a general formula CH2=CH-R wherein R is an organic material which imparts polymerizable character to the vinyl monomer.
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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 November 11, 1980. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended November 11, 1997.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledJanuary 21, 1977
GrantedNovember 11, 1980
Term endedNovember 11, 1997
Patent numberCA 1089575 A
Classification (IPC)C08L21/00 +2 more
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.