Release layer for an aqueous or semi-aqueous processible flexographic printing plate
CA 2069317 A1 · Owner: E.I. Du Pont De Nemours And Company · Inventors: Swatton, David W.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
This invention relates to a method to facilitate removal of a negative or positive image-bearing film from an aqueous or semi-aqueous processible flexographic printing element which comprises using a hydroxyalkyl cellulose release layer interposed between the image-bearing film and a photosensitive layer wherein the alkyl , group has from one to five carbon atoms. This invention also concerns an aqueous or semi-aqueous processible flexographic photosensitive element containing this release layer and to processes for making printing reliefs from such elements.
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 October 11, 1990. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended October 11, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 11, 2012.
- 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.