Microporous films
CA 1322425 C · Owner: Raychem Limited · Inventors: Park, George Barry; Cook, John Anthony
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention provides a method of making a polymeric film having a porosity of not less than 20% which comprises providing a film of a polymer composition the composition, comprising: (a) a halopolymer in which the repeat units are - (CnH2n)- and -(CmX2m)- where each X independently represents fluorine or chlorine and the values of n and m are greater than one or less than six; (b) an extractable salt and an extractable polymer which are substantially insoluble in the halopolymer; and subsequently extracting at least some of the extractable component so as to render the film porous.
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 September 21, 1993. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended September 21, 2010.
- 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.