Stabilization of thermal images
CA 2080098 A1 · Owner: Polaroid Corporation · Inventors: Liang, Rong C.; Schwarzel, William C.; Young, Michael A.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Abstract of the Disclosure, The addition to a thermal imaging medium comprising a color-forming compound which undergoes a change of color upon heating above a color-forming temperature for a color-forming time the color-forming compound, being of the cyclic sulfonamide type described in U.S. Patents Nos. 4,720,449 and 4,960,901, of a color-stabilizing additive comprising any one or more of a quinone a hydroquinone and a source of zinc, nickel copper(II), cobalt(II) or aluminum(III) cations, increases the sensitivity of the imaging medium and helps to prevent fading of images produced therefrom while the images are being projected.
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 7, 1992. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended October 7, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 7, 2014.
- 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.