Fast response photosensitive opal glasses
CA 2020882 A1 · Owner: Pierson, Joseph E. · Inventors: Stookey, Stanley D.; Pierson, Joseph E.; Dickinson, James E. Jr.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
This invention is directed to photosensitivity opacifiable glasses requiring very short exposures to ultraviolet radiation to effect the development of opacity therein during a subsequent heat treatment thereof. The glasses consist essentially, expressed in terms of weight percent on the oxide basis, of about 14 18% Na2O 0-6% ZnO, 6-12%, Al2O3, 0-5% B2O3, 65-72% SiO2 and 0-0.2% Sb2O3, and, 0.007-0.04% Ag, 0.008-0.05% Ceo2 0.7-1.25% Br, and 1.5-2.5%, F as analyzed in the glass the sum of those components, constituting at least 90% of the total composition.
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 July 11, 1990. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended July 11, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 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.