Polypropylene resin pre-expanded beads, manufacturing method thereof andexpansion-molding method using said beads
CA 1296150 C · Owner: Shiiki, Hitoshi · Inventors: Shiiki, Hitoshi; Nakamura, Kyoichi; Tada, Minoru
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention provides polypropylene resin preexpanded beads formed by shrinking polypropylene resin preexpanded beads originally having a bulk density of not higher than 0.0930 g/cc to give them a bulk volume ratio of 10 - 75 % at the normal temperature and the normal pressure a, manufacturing method thereof and an expansion-molding method with the aforementioned pre-expanded beads. According to this invention, it is possible to greatly reduce storing and transporting costs per unit weight of pre-expanded beads.
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 February 25, 1992. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended February 25, 2009.
- 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.