Polypropylene stretched film
CA 2001234 C · Owner: Ogawa, Tadatoshi · Inventors: Ogawa, Tadatoshi; Wakamatsu, Kazuki; Ima, Seiichiro
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The polypropylene stretched film of the present invention is prepared by stretching a composition comprising a crystalline propylene polymer and 0.1 ppm by weight to 10% by weight of a nucleating agent the, composition having a melting point of 160~C or more a crystallization temperature of 128~C or more and a 20~C xylene soluble portion of 3.0% by weight or less. The film has a high rigidity and a beautiful appearance as well as the characteristic properties inherent to crystalline propylene polymers. The film can be suitably used for food packaging and textile packaging.
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 October 23, 1989 and granted December 22, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 23, 2009.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 23, 2011.
- 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.