Process for producing porous films
CA 1250724 A · Owner: Mitsui Chemicals, Incorporated · Inventors: Suzuki, Hisatosi; Ito, Michiyasu; Tsuji, Shoichi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for producing porous films which comprises blending 100 parts by weight of a polyolefin resin with 50 to 500 parts by weight of barium sulfate preferably having an average particle diameter of 0.1 to 7 µm, melting the resulting resin composition and forming it into a film, and then stretching the film at least uniaxially by a factor of 1.5 to 7. As the polyolefin resin, there may preferably be used a polyethylene resin having a melt index of 0.5 to 7 and a density of 0.915 to 0.935, and more preferably a linear low-density polyethylene resin having a melt index of 0.5 to 8.5 and a density of 0.915 to 0.935. As the linear low-density polyethylene resin a copolymer of ethylene and …
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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 March 7, 1989. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended March 7, 2006.
- 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.