Process for producing biaxially oriented paraphenylene sulfide block copolymer film
CA 1301422 C · Owner: Kureha Kagaku Kogyo Kabushiki Kaisha · Inventors: Ichii, Takao; Iizuka, Yo; Mizuno, Toshiya
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Disclosed herein is a process for producing a biaxially oriented paraphenylene sulfide block copolymer film, comprising melt extruding and molding a paraphenylene sulfide block copolymer essentially composed:of recurring units (A): , and recurring units (B):, the molar fraction of recurring units (A) being 0.50 - 0.98, and having a melt viscosity (?*) of 1,000 - 50,000 poises as measured at 310°C and shear rate of 200 sec-1, into a film, and after cooling biaxially, stretching the thus molded film at a stretching temperature (T) defined by the following formula:, 96 - 50X < T < 116 - 66.7X wherein T is a stretching temperature (°C) and X is molar fraction of recurring units (B): , . - 40 -
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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 May 26, 1992. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended May 26, 2009.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.