Minimization of ripple by controlling gelatin concentration
CA 2090595 C · Owner: Eastman Kodak Company · Inventors: Kurz, Mark R.; Weinstein, Steven J.; Ruschak, Kenneth J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method of reducing the tendency toward formation of ripple imperfections in the coating of multilayer photographic elements is disclosed. Coating compositions are prepared for upper, middle and lower, gelatin-containing layers of a layered mass. The middle layer bas a gelatin concentration within three weight percent of each of the upper and lower layers and the upper, middle, and lower layers each have a viscosity that differs from a norm by no more than 15%. A laminar flow of a layered mass including the coating compositions is formed and then received as a layered coating on a moving support. A multilayer photographic element is also disclosed.
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 26, 1993 and granted January 7, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 26, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 26, 2015.
- 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.