Process for producing negative copies
CA 2031847 A1 · Owner: Elsaesser, Andreas · Inventors: Elsaesser, Andreas; Gaschler, Otfried; Frass, Hans W.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for producing negative copies is disclosed in which a light-sensitive or radiationsensitive recording material comprising a layer support and a normally positive-working lightsensitive or radiation-sensitive layer applied thereto is irradiated imagewise, thermally treated irradiated overall and then developed with an alkaline developer. Thermal treatment is carried out with water or with an aqueous solution at, temperatures in the range from about 50 to 100°C preferably from 60 to 90°C, within a period of time varying between about 1 second and 5 minutes preferably between 5 seconds and 1 minute overall, irradiation is performed on the optionally still hot recording material and …
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 December 10, 1990. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended December 10, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 10, 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.