Opaque film compositions
CA 1289709 C · Owner: Spitz, Joseph James · Inventors: Ashcraft, Charles Ray; Paul, Hee Chung Park; Spitz, Joseph James
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An opaque, biaxially oriented film structure is described which comprises:, an expanded thermoplastic polymer matrix core layer within which is located a minor amount of a light-absorbing pigment and a strata of voids; positioned at least substantially within at least a substantial number of said voids is at least one void-initiating particle which is phase distinct and incompatible with the matrix material, the void space occupied by said particle being substantially less than the volume of said void with one generally, cross-sectional dimension of said particle at least approximating a, corresponding cross-sectional dimension of said void; the population of voids in said core and the …
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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 October 1, 1991. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended October 1, 2008.
- 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.