Base film for photographic film
CA 2118252 C · Owner: Okamoto, Hiroshi · Inventors: Katoh, Kohtaro; Tomita, Hiroshi; Suzuki, Kenji
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
72-, A base film for a photographic film wherein, (a) the refractive index (nz) in the thickness direction is at least 1.498, (b) the haze value is 2.0 % or less, (c) the base film has one direction in which the tan .delta. value, at 80°C by tensile viscoelasticity at 0.05 Hz, is 0.09 or less, (d) the anti-curling ratio at 70°C is at least 45 %, (e) the thickness is in the range of from 40 to 120 µm, and (f) the base film is formed from polyethylene-2,6-naphthalendedicarboxylate as a substantial raw material. This base film has various performances such as anti-curling properties transparency and lubricity, suitable for use in a photographic film.
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 February 7, 1994 and granted October 24, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 7, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 7, 2016.
- 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.