Process for the preparation of expandable styrene polymer particles
CA 1049199 A · Owner: Sekisui Kaseihin Kogyo Kabushiki Kaisha · Inventors: Ikeda, Toshiki; Ishida, Tomohiko; Yamai, Fumito
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for preparing expandable styrene polymer particles by using magnesium oxide as a suspending agent to prevent agglomeration of styrene polymer particles during impregnation with an expanding agent. The process comprises preparing expandable styrene polymer particles from styrene polymer particles in water, wherein the expanding agent (which does not dissolve styrene polymer particles or slightly swells the particles and has a boiling point lower than the softening point of the particles) is added in the presence of the suspending agent and the particles being impregnated thereby.
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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 February 20, 1979. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended February 20, 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.